MX2011009550A

MX2011009550A - Transgenic plants with altered redox mechanisms and increased yield.

Info

Publication number: MX2011009550A
Application number: MX2011009550A
Authority: MX
Inventors: Bryan Mckersie
Original assignee: Basf Plant Science Co Gmbh
Priority date: 2009-03-23
Filing date: 2010-03-17
Publication date: 2011-10-12
Also published as: AR075918A1; AU2010227625A1; DE112010001241T5; EP2411524A1; BRPI1006259A2; WO2010108836A1; CN102361988A; AU2010227625A2; CA2754916A1

Abstract

Polynucleotides are disclosed which are capable of enhancing yield of a plant transformed to contain such polynucleotides. Also provided are methods of using such polynucleotides, and transgenic plants and agricultural products, including seeds, containing such polynucleotides as transgenes.

Description

TRANSGENIC PLANTS WITH ALTERATED AND MAJOR REDOX MECHANISMS PERFORMANCE i FIELD OF THE INVENTION The present application claims the priority benefit of the US provisional patent application number 61 / 162,427, filed on March 23, 2009, the content of which is hereby incorporated by reference in its entirety. j BACKGROUND OF THE INVENTION In recent years, population growth and climate change have highlighted the possibility of shortages of food for humans, animal feed and fuel worldwide. Agriculture consumes 70% of the water that people use, while rainfall decreases in many parts of the world. In addition, because the use of land changes from farms to towns and suburbs, there are fewer hectares of arable land available for the development of agricultural crops. Agricultural biotechnology has attempted to meet the growing needs of men through genetic modifications of plants that could increase crop yields, for example by conferring better tolerance to responses to abiotic stress or increasing biomass. .

At present, crop yield is defined as the number of bushels of relevant agricultural product (such as grain, fodder or seed) harvested per acre. The different types of abiotic stress, such as stress due to drought, heat, salinidation and cold, and the size (biomass) of the plant impact on crop yield. The traditional strategies of plant reproduction are relatively slow and, in general, failed to confer greater tolerance to abiotic stress. In the case of corn, improvements in grain yield through traditional breeding have practically stagnated. In the last hundred years, the maize harvest index, that is, the ratio between yield biomass and total cumulative biomass during harvest, has practically not changed during selective breeding for grain yield. Accordingly, the recent yield improvements in maize are the result of increased production of total biomass per unit of land area. The increase in total biomass was achieved by increasing the density of the plantation, which generated adaptive phenotypic alterations, such as reduction of the angle of the leaf, which can reduce the shade of the lower leaves, and the size of the male inflorescences of corn, which can increase the harvest index.

When soil water runs out or there is no water available during periods of drought, crop yields decrease. Water deficit occurs in the plants if the transpiration of the leaves exceeds the supply of water from the roots. The available water supply is related to the amount of water in the soil and the ability of the plant to reach the water with its root system. The transpiration of water from the leaves is linked to the fixation of carbon dioxide through photosynthesis through stomata. The two processes correlate positively, so that the high influx of carbon dioxide by photosynthesis is closely linked to the loss of water by transpiration. As the leaf transpires water, the water potential of the leaf is reduced and the stomas tend to close in a hydraulic process that limits the amount of i photosynthesis. Because the yield of crops depends on the fixation of carbon dioxide in photosynthesis, water absorption and transpiration are factors that contribute to crop yields. Plants able to use less water to fix the same amount of carbon dioxide or to operate normally with a lower water potential can generate more photosynthesis and, therefore, produce more biomass and economic yield in many agricultural systems.

Agricultural biotechnologists used trials in model plant systems, greenhouse studies of crop plants and field trials in an attempt to develop transgenic plants that exhibited higher yields, either by increasing tolerance to abiotic stress or increasing biomass . For example, water use efficiency (WUE) is a parameter that is often correlated with tolerance to drought. Studies of the plant's response to dehydration, osmotic shock, and extreme temperatures are also used to determine the tolerance or resistance of the plant to abiotic stress.

An increase in biomass in conditions of low water availability can be due to relatively improved growth efficiency or low water consumption. When selecting traits to improve crops, a decrease in water use, without changes in growth, would be particularly important in an irrigated agricultural system, in which the costs of water supply are high. An increase in growth without a corresponding increase in water use would apply to all agricultural systems. In many agricultural systems where the water supply is not limiting, a Increased growth, even if it is at the expense of an increase in water use, also increases performance.

Agricultural biotechnologists also use measurements of other parameters that indicate the possible impact of a transgene on crop yields. For forage crops such as alfalfa, silage and hay, the biomass of the plant correlates with the total yield. However, for the grain crops other parameters were used to calculate the yield, such as plant size, measured by the total dry weight of the plant, aerial dry weight, fresh air weight, leaf area, stem volume, plant height, rosette diameter, leaf length, root length, root mass, number of stems and number of leaves. The size of the plant at an early stage of development usually correlates with the size of the plant at a later stage of development. A larger plant with a larger leaf area can usually absorb more light and carbon dioxide than a smaller plant and, therefore, will probably gain more weight during the same period. There is a strong genetic component that determines the size and speed of growth of the plant and, therefore, for various genotypes, it is possible that the size of the plant in a certain environmental condition correlates with the size in another. In this way, a standard environment is used that resembles the diverse dynamic environments that crops in the field face in different places and times.

The harvest index is relatively stable under various environmental conditions and, therefore, it is possible that there is a strong correlation between the size of the plant and the yield of the grain. The size of the plants and the yield of the grains are intrinsically linked because the majority of the biomass of the grain depends on the current or stored photosynthetic productivity of the leaves and the stem of the plant. As with tolerance to abiotic stress, measurements of plant size in early development, under standardized conditions in a growth chamber or in a greenhouse, are standard practices for measuring the potential performance advantages that presence provides. of a transgene.

Plants can not move to find sources of energy or to avoid predation or stress. As a result, the plants developed several networks and biochemical pathways to respond to the environment, which maintain the energy supply to the plant under development in various environmental conditions. One of the problems that plants face in these adverse conditions, such as drought, extreme temperatures and exposure to heavy metals, is that some metabolic products are highly toxic.

In the case of oxidative stress, these toxins include the highly reactive oxygen species (ROS) of superoxide, peroxide, hydroxyl radicals and their organic derivatives. ROS are highly reactive to organic molecules, such as unsaturated lipids, nucleic acids and proteins. The ROS extract hydrogen from these organic molecules, which generates the formation of reduced oxygen (water or a reduced organic product) and a second organic ROS, which prolongs a chain reaction that generates the continuous destruction of cellular components until the ROS is kidnapped. ROS sequestration involves the formation of a non-reactive end product that is not a ROS species. It is known that several hydrogen donors that act as ROS scavengers work in plant cells, including tocopherol, ascorbate, glutin and thioredoxin. These various ROS scavengers share two common characteristics: the oxidized form is not reactive to other organic compounds and the oxidized form can be reduced by metabolic reactions in the cell to regenerate the reduced form of the sequestrant in a cyclic reaction that directly or indirectly reduces equivalents of NAD (P) H.

Oxidative stress occurs in plants under adverse environmental conditions when the production of ROS formed as a byproduct of metabolism exceeds the capacity of the sequestering system of the plant to dissipate ROS in stable end products. To cope with oxidative stress, the plant cell must contain adequate amounts of sequestrants or enzymes capable of inactivating ROS. In addition, the cell also requires an adequate supply of reducing equivalents in the form of NAD (P) H to regenerate the active form of the sequestrant. If none is adequate, the ROS titrant increases and the cell suffers oxidative damage to lipids, nucleic acids or proteins. In severe cases, this damage can cause cell death, necrosis and loss of productivity. ' Glutathione was detected in almost all cell compartments, such as cytosol, chloroplasts, endoplasmic reticulum, vacuoles and mitochondria. Glutathione is the main source of non-protein thiols in plant cells; The chemical reactivity of the thiol group makes glutathione participate in several biochemical functions. Glutathione is hydrosoluble, stable, and in addition to detoxifying ROS, it also provides protection against other types of stress, such as heavy metals, organic chemicals and pathogens. The soluble enzyme, "classical" glutathione peroxidase, converts the reduced monomeric glutathione (GSH) with H202 in its oxidized form, glutathione disulfide (GSSG) and H20. The cellular redox balance of a cell indicates the GSH / GSSG ratio and it was suggested that it participates in the perception and ROS signage. The second form of glutathione peroxidase, phospholipid Hydroperoxide glutathione peroxidase (PHGPx), may be associated with the membrane. PHGPx is associated with various functions, such as cell signaling and differentiation, and may be linked to the thioredoxin pathway. PHGPx also reduces esterified lipid hydroperoxides in membranes. Therefore, it is associated with PHGPx with the repair of membrane lipid peroxidation.

Glutathione also participates in glutathionylation, which modifies proteins1 by protecting specific cysteine residues from irreversible oxidation, to regulate the activity of certain proteins in this way. The enzyme isocitrate lyase is deactivated by glutathionylation. Isocitrate lyase catalyzes the formation of succinate and isocitrate glyoxylate, part of the glyoxylate cycle, which converts two molecules of acetyl-CoA into a molecule of succinate.

Glutathione can also be degraded by the action of gamma-glutamyltranspeptidase, which catalyzes the transfer of the gamma-glutamyl portion of glutathione to an acceptor that can be an amino acid, a peptide or water. Based on the homology in animal GGTs, four genes were found in Arabidopsis: GGT1, GGT2, GGT3 and GGT4. GGT1 represents 80-99% of the activity, except in the 'seeds, where GGT2 represents 50% of the activity. The knockout of GGT2 and GGT4 do not show an apparent phenotype, but the knockout of GGT1 has premature senescence of the rosettes shortly after flowering. GGT3 knockouts show lower amount of siliques and lower seed yield.

Reduction-oxidation (redox) reactions occur when atoms undergo a change in their oxidative state, through an electron transfer reaction. Oxidation describes a gain of the oxidation state by hydrogen loss or oxygen gain. The reduction describes a loss of the oxidation state by hydrogen gain or oxygen loss. In biology, several important energy release or storage pathways include redox reactions. Cell respiration oxidizes glucose at C02 and reduces 02 to water. In photosynthesis, C02 is reduced to sugars and H2O is oxidized in 02 in Photosystem II. In Photosystem I, the electron gradient reduces the cofactor NAD + to NADH. A proton gradient is produced, generating the synthesis of ATP, as occurs in the respiratory chain, which extracts by bombéo H +; the H + that transports ATP synthase couples the absorption of H + to the synthesis of ATP. In non-photosynthetic organisms, such as £ coli, redox reactions can interchange electrons and use hydrogen as an energy source to allow anaerobic growth, which requires the action of hydrogenases.

The redox state of a cell mainly reflects the ratio NAD + / NADH or NADP + / NADPH. This balance is reflected in the amount of metabolites, such as pyruvate and lactate. The growth of the plant requires the supply of carbon, ATP, NADH and NADPH. These requirements can be met by glycolysis and the pentose phosphate pathway, which provides an oxidative pathway to regenerate NADPH and a non-oxidative pathway to produce ribose and other hexose pentoses found in metabolism. Transaldolase is an enzyme in the non-oxidative pathway of pentose phosphate that catalyzes the reversible transfer of the three-carbon cetol unit from sedoheptulose-7-phosphate to glyceraldehyde-S-phosphate to form erythrose-4-phosphate and fructose-6-phosphate. Transaldolase, together with transketolase, provides a link between the glycolytic and pentose phosphate pathways.

The metabolism of galactose plays a role in cellular metabolism by providing glucose for the metabolism of fructose and mannose, sugar metabolism of nucleotides and glycolysis. The transformation of galactose into glucose-1-phosphate requires the action of three enzymes via the Leloir pathway: galactoquinasa, galactpsa-1-phosphate uridyliltransferase and UDP-galactose 4-epimerase. Galactokinase specifically phosphorylates galactose by the use of ATP to form galactose-1-phosphate in the first stage of the pathway.

Although some genes that are involved in the responses to stress, the use of water and / or biomass in plants were characterized, up to now attempts to develop transgenic crop plants with better yields have been limited, and these plants are not commercialized. Therefore, it is necessary to identify other genes that have the ability to increase the yield of crop plants.

SYNTHESIS OF THE INVENTION The inventors of the present discovered the alterations of the expression of genes related to the sequestering system of ROS in plants can improve the performance of the plant. When directed as described herein, the polynucleotides and polypeptides indicated in Table 1 are capable of improving the yield of the transgenic plants.

I i Table 1 In one embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length galactokinase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter and an isolated polynucleotide encoding a polypeptide of I ? full-length transaldolase A; wherein the transgenic plant shows higher yield, as compared to a wild-type plant of the same variety that does not comprise the expression cassette. j In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter and an isolated polynucleotide encoding a full length accessory hydrogenase-2 polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter capable of enhancing gene expression in the leaves; an isolated polynucleotide encoding a transit peptide to mitochondria; and an isolated polynucleotide encoding a full length isocitrate Nasa polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full-length phospholipid hydroperoxide polypeptide glutathione peroxidase; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter and an isolated polynucleotide encoding a full-length gamma-glutamyltranspeptidase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide that encodes a transit peptide to mitochondria; and an isolated polynucleotide encoding a polypeptide of subunit B 'of ATP full-length synthase; where the transgenic plant shows higher yield, compared to a wild type plant of the same variety that does not includes the expression cassette. ! In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length 0-22 sterol desaturase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.

In another embodiment, the invention provides a seed produced by the transgenic plant of the invention, wherein the seed is genetically pure line for a transgene comprising the expression vectors described above. The plants derived from the seed of the invention show greater tolerance to environmental stress and / or higher plant growth and / or higher yield, under normal and / or stress conditions, compared to a wild-type variety of the plant.

In yet another aspect, the invention relates to products produced by or from the transgenic plants of the invention, the plant parts, or their seeds; such as food products for humans, food products for animals, food supplements for humans, food supplements for animals, fibers, cosmetics or pharmaceutical products.

The invention also provides certain isolated polynucleotides identified in Table 1 and certain isolated polypeptides identified in Table 1. The invention is also expressed in a recombinant vector comprising an isolated polynucleotide of the invention.

In yet another embodiment, the invention relates to a method for producing the aforementioned transgenic plant, wherein the method comprises transforming a plant cell with an expression vector comprising an isolated polynucleotide of the invention and generating a transgenic plant. of the plant cell expressing the polypeptide encoded by the polynucleotide. Expression of the polypeptide in plants results in greater tolerance to environmental stress and / or increased growth and / or yield, under normal and / or stress conditions, compared to a wild-type variety of the plant.

In yet another embodiment, the invention provides a method for increasing the I I tolerance of a plant to environmental stress and / or growth and / or yield. The method comprises the steps of transforming a plant cell with an expression cassette comprising an isolated polynucleotide of the invention and generating a transgenic plant of the plant cell, wherein the transgenic plant comprises the polynucleotide.

I BRIEF DESCRIPTION OF THE DRAWINGS I Figure 1 shows an alignment of amino acid sequences of the galactokinase called b0757 (SEQ ID NO: 2), GM59594085 (SEQ ID NO: 4), GM59708137 (SEQ ID NO: 6) and ZMBFb0152K10 (SEQ ID NO: 8) . The alignment was generated with Align X of Vector NTI. 1 Figure 2 shows an alignment of amino acid sequences of the transaldolase A proteins designated b2464 (SEQ ID NO: 10), BN43182918 (SEQ ID NO: 12) and GM48926546 (SEQ ID NO: 14). The alignment was generated with Align X of Vector NTI.

Figure 3 shows an alignment of amino acid sequences of the phospholipid hydroperoxide glutathione peroxidases designated YIR037W. { SEQ ID NO: 20), BN4226 838 (SEQ ID NO: 22), BN43722096 (SEQ ID NO: 24), BN51407729 (SEQ ID NO: 26), GM50585691 (SEQ ID NO: 28), GMsa56c07 (SEQ ID NO: 30), GMsp82f11 (SEQ ID NO: 32), GMss66f03 (SEQ ID NO: 34), HA03MC1446 (SEQ ID NO: 36), HV03MC9784 (SEQ ID NO: 38), OS34914218 (SEQ ID NO: 40), ZM61990487 ( SEQ ID NO: 42) and ZM68466470.r01 (SEQ ID NO: 44). The alignment was generated with Align X of Vector NTI. 1 Figure 4 shows an alignment of amino acid sequences of the ATP synthase B 'subunit proteins designated SLL1323 (SEQ ID NO: 48) and Gmsb38b04 (SEQ ID NO: 50). The alignment was generated with Align X of Vector NTI.

Figure 5 shows an alignment of amino acid sequences of the C-22 esteral desaturases designated YMR015C (SEQ ID NO: 52) and GMso65h07 (SEQ ID NO: 54). The alignment was generated with Align X of Vector NTI.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present specification, reference is made to various publications. The descriptions of all of these publications and the references cited in said publications are hereby incorporated by reference in their entirety, in order to more fully describe the state of the art to which the present invention pertains. The terminology used herein is for the purpose of describing only specific embodiments i I and does not intend to limit them. As used herein, "an" or "an" can mean one or more, depending on the context in which it is used. Accordingly, for example, the reference to "one cell" can mean that at least one cell is used.

In one embodiment, the invention provides a transgenic plant that overexpresses an isolated polynucleotide identified in Table 1 in the compartment. subcellular and tissue indicated herein. The transgenic plant of the invention shows better yield, as compared to a wild type variety of the plant. As used herein, the term "best yield" means an improvement in the yield of any measured plant product, such as grain, fruit or fiber. According to the invention, changes in different phenotypic traits can improve performance. For example, and without limitation, the parameters, such as floral organ development, root start, root biomass, seed quantity, seed weight, harvest index, tolerance to abiotic environmental stress, leaf formation, Phototropism, apical dominance and fruit development are adequate measurements of the best performance. According to the invention, an increase in performance is better performance. For example, the performance improvement may comprise an increase of 0.1%, 0.5%, 1%, 3%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or greater in any parameter measured. For example, according to the invention, an increase in the yield per bu / acfe of soy or corn derived from a culture comprising plants that are transgenic for the nucleotides and polypeptides of Table 1, compared to the yield pqr bu / acre of soybeans or corn not treated under the same conditions, better yield according to the invention.

I As defined herein, a "transgenic plant" is a plant that was altered by recombinant DNA technology to contain an isolated nucleic acid that would not otherwise be present in the plant. As used in the present, the term "plant" includes whole plants, plant cells and parts of plants. Plant parts include, without limitation, stems, roots, ovules, stamens, leaves, embryos, meristematic regions, callus tissues, gametophytes, sporophytes, pollen, microspores and the like. The transgenic plant of the invention may be sterile male or fertile male, and may also include transgenes other than those comprising the isolated polynucleotides described herein. i As used herein, the term "variety" refers to a group of plants of a species that share constant characteristics that differentiate them from the typical form I and other possible varieties of that species. While it has at least one distinctive feature, a variety is also characterized by some variation among individuals of the variety, which is based primarily on Mendelian segregation of traits among the progeny of successive generations. A variety is considered "genetically pure line" for a particular trait, if it is genetically homozygous for that trait, insofar as, when the genetically pure line variety self-pollinates, a considerable amount of feature-independent segregation is not observed among the progeny In the present invention, the trait arises from the transgenic expression of one or more isolated nucleotides introduced into a plant variety. As also used herein, the term "wild-type variety" refers to a group of plants that are analyzed for comparative purposes as a control plant, wherein the variety of wild-type plant is identical to the transgenic plant (plant transformed with an isolated polynucleotide according to the invention) with the exception that the wild-type plant variety was not transformed with an isolated polynucleotide of the invention. As used herein, the term "wild type" refers to a plant cell, seed, plant component, plant tissue, plant organ or whole plant that was not genetically modified with an isolated polynucleotide according to the invention. invention.

As used herein, the term "control plant" refers to a plant cell, an explant, seed, plant component, plant tissue, organ! of plant or whole plant used to compare with a transgenic or genetically modified plant, in order to identify an improved phenotype or a desirable trait in the transgenic or genetically modified plant. In some cases, a "control plant" can be a transgenic plant line comprising a marker gene or empty vector, but not containing the recombinant polynucleotide of interest that is present in the transgenic or genetically modified plant being evaluated. A control plant can be a plant of the same line or variety as the transgenic or genetically modified plant that is evaluated, or can be of another line or variety, such as a plant known to have a specific known phenotype, characteristic or genotype. . A suitable control plant would include a non-transgenic or non-genetically modified plant of the parental line used to generate a transgenic plant hereof.

As defined herein, the terms "nucleic acid" and "polynucleotide" are indistinct and refer to RNA or DNA that is linear or branched, mono- or double-stranded, or a hybrid thereof. The term also encompasses RNA / DNA hybrids. An acid molecule I I "Isolated" nucleic acid is substantially separated from other nucleic acid molecules that are present in the natural source of the nucleic acid (ie, sequences encoding other polypeptides). For example, a cloned nucleic acid is considered isolated. A nucleic acid is also considered isolated if it was altered by human intervention, or placed in a locus or location that is not its natural site, or if it is introduced into a cell by transformation. Also, an isolated nucleic acid molecule, such as a cDNA molecule, may be free from part of the other cellular material with which it is naturally associated, or culture medium when produced by recombinant techniques,? chemical precursors or other chemical products when chemically synthesized. While it may optionally include untranslated sequences located at the 3 'and 5' ends of the coding region of a gene, it may be preferable to remove flanking sequences. naturally the coding region in its natural replicon.

As used herein, the term "environmental stress" refers to sub-optimal conditions associated with stress of salinity, drought, nitrogen, temperature, metal, chemicals, pathogens or oxidative stress, or any combination of these. As used herein, the term "drought" refers to an environmental condition wherein the I amount of water available to support the growth or development of the plant is suboptimal. As used herein, the term "fresh weight" refers to everything found in the plant, including water. As used herein, the term "dry constipation" refers to everything found in the plant other than water and includes, for example, carbohydrates, proteins, oils and mineral nutrients.

According to the invention, any plant species can be transformed to create a transgenic plant. The transgenic plant of the invention can be a dicotyledonous plant or a monocotyledonous plant. For example, and without limitation, the transgenic plants of the invention can derive from any of the following families of dicotyledonous plants: Leguminosae, which includes plants such as peas, alfalfa and soy; Umbelliferae, which includes plants such as carrots and celery; Solanaceae, which includes plants such as tomato, potato, eggplant, tobacco and pepper; Cruciferae, in particular, the genus Brassica, which includes plants such as oilseed rape, beet, cabbage, cauliflower and broccoli); and A. thaliana; Compositae, which includes plants such as Malvaceae lettuce, which includes cotton; Fabaceae, which includes plants such as peanuts and the like. The transgenic plants of the invention can be derived from monocotyledonous plants, such as, for example, wheat, barley, sorghum, millet, rye, triticale, corn, rice, oats and sugarcane.

The transgenic plants of the invention also include trees, such as apple tree, pear, quince, plum, cherry, peach, nectarine, damask, papaya, mango and other woody species, which include coniferous and deciduous trees, such as poplar, pine, sequoia, cedar, oak and similar. Especially preferred are Arabidopsis thaliana, Nicotiana tabacum, rice, oilseed rape, cañola, soybean, corn, cotton and wheat.

In one embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a peptide or transit to chloroplast; and an isolated polynucleotide encoding a full length galactokinase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, transgenic Arabidopsis plants containing the b0757 gene from E. coli (SEQ ID NO: 1) that targets the chloroplast, show higher yield, compared to the Arabidopsis control plants . The b0757 gene encodes galactokinase and is characterized, in part, by the presence of the characteristic sequences GHMP_kinases_C (Pfam: PF08544) and GHMP_kinases_N (PF00288). These characteristic sequences are exemplified in the galactokinase proteins indicated in Figure 1.

The transgenic plant of this embodiment may comprise any polynucleotide that encodes a galactokinase polypeptide. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full length polypeptide having galactokinase activity, eg where the polypeptide comprises at least one selected characteristic sequence of GHMP_kinases_C and GHMP_kinases_N, where the characteristic sequence GHMP_kinases_C is selected of the group consisting of amino acids 278 to 362 of SEQ ID NO: 2; amino acids 378 to 426 of SEQ ID NO: 4; amino acids 326 to 404 of SEQ ID NO: 6; and amino acids 391 to 473 of SEQ ID NO: 8; and wherein the characteristic sequence GHMP_kinases_N is selected from the group consisting of amino acids 1 | 14 to 182 of SEQ ID NO: 2; amino acids 152 to 219 of SEQ ID NO: 4; amino acids 138 to 205 of SEQ ID NO: 6; and amino acids 159 to 226 of SEQ ID NO: 8. Preferably, the polypeptide comprises a characteristic sequence GHMP_kinases_C and a characteristic sequence GHMP_kinases_N. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a galactokinase polypeptide that i has a sequence selected from the group consisting of amino acids 1 to 382 of SEQ ID NO: 2; amino acids 1 to 460 of SEQ ID NO: 4; amino acids 1 to 431 of SEQ ID NO: 6; and amino acids 1 to 504 of SEQ ID NO: 8. I In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated F oligonucleotide encoding a promoter; and an isolated polynucleotide encoding a full-length transaidolase A polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, transgenic Arabidopsis plants containing the b2464 gene from E. coli (SEQ ID NO: 9), which encodes a trans-a-lase A polypeptide, and the transgenic plants of this embodiment show greater performance, compared to the Arabidopsis control plants. The transaidolase A polypeptides are characterized, in part, by the presence of a characteristic sequence of Transaidolase (PF00923). These characteristic sequences are exemplified in the transaidolase A proteins indicated in Figure 2.

The transgenic plant of this embodiment may comprise any polynucleotide that encodes a transaidolase A protein. Preferably, the transgenic plant of this embodiment comprises a polynucleotide that encodes a full-length polypeptide having transaidolase A activity, wherein the polypeptide it comprises a characteristic sequence of transaidolase selected from the group consisting of amino acids 12 to 312 of SEQ ID NO: 10; amino acids 1 to 275 of SEQ ID NO: 12; and amino acids 1 to 277 of SEQ ID NO. 14. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a transaidolase A polypeptide having a sequence selected from the group consisting of amino acids 1 to 316 of SEQ ID NO: 10; amino acids 1 to 284 of SEQ ID NO: 12; and amino acids 1 to 283 of SEQ ID NO: 14.

In another embodiment, the invention provides a transgenic plant transformed i with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; and an isolated polynucleotide encoding a full-length accessory hydrogenase-2 polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, transgenic Arabidopsis plants containing the E. coli b2990 gene (SEQ ID NO: 15) showed higher yield, compared to Arabidopsis control plants. The b2990 gene encodes an accessory protein of hydrogenase-2. In E. coli under anaerobic conditions, this protein is an accompanying type protein necessary for the generation of active hydrogenase-2, which is an absorption hydrogenase [NiFe] which, together with hydrogenase 1, couples the oxidation of H2 to the fumarate reduction The accessory proteins of hydrogenase-2 are characterized, in part, by the presence of a characteristic sequence HupF_HypC (PF01455).

The transgenic plant of this embodiment may comprise any polynucleotide that encodes an accessory protein of hydrogenase-2. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full-length polypeptide having hydrogenase assembly companion activity, wherein the polypeptide comprises a characteristic sequence | HupF_HypC comprising amino acids 1 to 79 of SEQ ID NO: 16. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding an accessory protein of hydrogenase-2 having a sequence comprising amino acids 1 to 82 of SEQ ID NO: 16.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter capable of enhancing gene expression in the leaves; an isolated polynucleotide that encodes a transit peptide to mitochondria; and an isolated polynucleotide encoding a full length isocitrate Nasa polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, the transgenic Arabidopsis plants containing the gene S. cerevisiae YER065C (SEQ ID NO: 17) coding for isocitrate lyase and targeting the mitochondria, show higher yield, as compared to plants of control of Arabidopsis. The isocitrate lyases are characterized, in part, by the presence of a characteristic ICL sequence (PF00463).

The transgenic plant of this embodiment may comprise any polynucleotide that encodes an isocitrate lyase. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full length polypeptide having isocitrate lyase activity, wherein the polypeptide comprises a characteristic ICL sequence comprising amino acids 22 to 550 of; SEQ ID NO: 18. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a Nasa isocitrate having a sequence comprising amino acids 1 to 557 of SEQ ID NO: 18.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length phospholipid hydroperoxide polypeptide glutathione peroxidase; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, the transgenic Arabidopsis plants containing the gene S. cerevisiae YIR037W (SEQ ID NO: 19) that targets the chloroplast, show higher yield, compared to the Arabidopsis control plants. The YIR037W gene encodes a protein phospholipid hydroperoxide glutathione peroxidase, which functions as a sensor of intracellular hyperoxide levels and a transducer of the redox signal of the transcription factor Yap1, which regulates the levels of hyperoxide in S. cerevisiae. The phospholipid hydroperoxide glutathione peroxidases are characterized, in part, by the presence of a characteristic GSHPx sequence (PF00255) representative of the glutathione peroxidase gene family. These characteristic sequences are exemplified in the phospholipid hydroperoxide glutathione peroxidases indicated in Figure 3.! The transgenic plant of this embodiment may comprise any polynucleotide encoding a phospholipid hydroperoxide glutathione peroxidase. Preferably, the transgenic plant of this embodiment comprises a polynucleotide that encodes a full length polypeptide having phospholipid hydroperoxide glutathione peroxidase activity, wherein the polypeptide comprises a GSHPx characteristic sequence selected from the group consisting of amino acids 4 to 111 of SEQ ID NO: 20; amino acids 10 to 118 of SEQ ID NO: 22; amino acids 37 to 145 of SEQ ID NO: 24; amino acids 9 to 117 of SEQ ID NO: 26; amino acids 9 to 117 of SEQ ID NO: 28; amino acids 9 to 117 of SEQ ID NO: 30; amino acids 12 to 120 of SEQ ID NO: 32; amino acids 12 to 120 of SEQ ID NO: 34; amino acids 11 to 119 of SEQ! ID NO: 36; amino acids 12 to 120 of SEQ ID NO: 38; amino acids 9 to 117 of SEQ ID NO: 40; amino acids 12 to 120 of SEQ ID NO: 42; and amino acids 24 to 132 of SEQ ID NO: 44. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a phospholipid hydroperoxide glutathione peroxidase having a sequence selected from the group consisting of amino acids 1 to 163 of SEQ ID NO: 20; amino acids 1 to 169 of SEQ ID NO: 22; amino acids 1 to 201 of SEQ ID NO: 24; amino acids 1 to 169 of SEQ ID NO: 26; amino acids 1 to 166 of SEQ j ID NO: 28; amino acids 1 to 166 of SEQ ID NO: 30; amino acids 1 to 170 of SEQ ID NO: 32; amino acids 1 to 170 of SEQ ID NO: 34; amino acids 1 to 185 of SEQ j ID NO: 36; amino acids 1 to 176 of SEQ ID NO: 38; amino acids 1 to 166 of SEQ ID NO: 40; amino acids 1 to 170 of SEQ ID NO: 42; and amino acids 1 to 182 of SEQ ID NO: < Four.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; and an isolated polynucleotide encoding a full-length gamma-glutamyltranspeptidase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild-type plant of the same variety that does not comprise the expression cassette. Optionally, the expression cassette also comprises an isolated polynucleotide that encodes a chloroplast transit peptide, in operative association with the isolated polynucleotide encoding a promoter and the isolated polynucleotide encoding a full length gamma-glutamyltranspeptidase polypeptide. As indicated in Example 2 below, transgenic Arabidopsis plants containing the slr1269 gene from Synechocystis sp. (SEQ ID NO: 45) which encodes a gamma-glutamyltranspeptidase polypeptide, show higher yield, compared to the Arabidopsis control plants. The gamma-glutamyltranspeptidase are characterized, in part, by the presence of a characteristic sequence IG_glu_transpept (PF01019).

The transgenic plant of this embodiment may comprise any polynucleotide encoding a gamma-glutamyltranspeptidase. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full-length polypeptide having gamma-glutamyltranspeptidase activity, wherein the polypeptide comprises a characteristic G_glu_transpept sequence comprising amino acids 21 to 51 1 of SEQ ID NO: 46. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a gamma-glutamyltranspeptidase having a sequence comprising amino acids 1 to 518 of SEQ ID NO: 46.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, a pplinucleotide I isolated that encodes a promoter; an isolated polynucleotide that encodes a transit peptide to mitochondria; and an isolated polynucleotide encoding a polypeptide of the B 'subunit of full-length ATP synthase; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. As indicated in Example 2 below, transgenic Arabidopsis plants containing the SLL1323 gene from Synephocystis sp. (SEQ ID NO: 47) that targets the mitochondria, show higher yield, compared to the Arabidopsis control plants. The SLL1323 gene encodes a protein of the B 'subunit of ATP synthase. Subunits B and B 'are of the FO complex in F-ATPases that are found in chloroplasts and bacterial plasma membranes and are part of the peripheral peduncle that binds F1 and FO complexes together. The proteins of the B 'subunit of ATP synthase are characterized, in part, by the presence of a characteristic sequence ATP-synt_B (PF00430) representative of the gene family B / B' CF (0) of ATP synthase. These characteristic sequences are exemplified in the proteins of the B 'subunit of ATP synthase indicated in Figure 4.

The transgenic plant of this embodiment may comprise any polynucleotide that encodes a protein of the B 'subunit of ATP synthase. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full-length polypeptide having activity of the B 'subunit of ATP synthase, wherein the polypeptide comprises a characteristic sequence ATP-synt_B selected from the group consisting of amino acids 7 to 138 of SEQ ID NO: 48 and amino acids 82 to 213 of SEQ ID NO: 50. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide 'which encodes a protein of the B' subunit of ATP synthase. having a sequence comprising amino acids 1 to 143 of SEQ ID NO: 48 and amino acids 1 to 215 of SEQ ID NO: 50.

In another embodiment, the invention provides a transgenic plant transformed with an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full-length C-22 sterol desaturase polypeptide; wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette. The YMR015C gene (SEQ ID NO: 51) encodes a C-22 sterol desaturase, which is a cytochrome P450 enzyme (ERG5) which, in yeast, catalyzes the I i í formation of the double ligature C-22 (23) in the sterol side chain in the ergosterol biosynthesis. The enzymes of C-22 sterol desaturase are characterized, in part, by the presence of a K-helix motif (xExxR), a consensus sequence PER ^ (PxRx) and a FGRCG motif surrounding the protoporphyrin IX ligand hemocysteine near the terminal C. Those conserved motifs are exemplified in the C-22 sterol desaturase polypeptides indicated in Figure 5. i The transgenic plant of this embodiment may comprise any polynucleotide that encodes a C-22 sterol desaturase. Preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a full-length polypeptide having C-22 sterol desaturase activity, wherein the polypeptide comprises a domain comprising a K-helix motif, a PERF motif and a motif. FGRCG, wherein the helix motif K has a sequence selected from the group consisting of amino acids 395 to 398 of SEQ ID NO: 52 and amino acids 365 to 368 of SEQ ID NO: 54; the PERF motif has a sequence selected from the group consisting of amino acids 450 to 453 of SEQ ID NO: 52 and amino acids 418 to 421 of SEQ ID NO: 54; and the FGRCG motif has a sequence selected from the group consisting of the amino acids 469 to 478 of SEQ ID NO: 52 and amino acids 438 to 447 of SEQ ID NO: 54. Most preferably, the polynucleotide encodes a full-length polypeptide that has activity í of C-22 sterol desaturase, wherein the polypeptide comprises a domain selected from the group consisting of amino acids 61 to 529 of SEQ ID NO: 52 and amino acids 27 to 498 of SEQ ID NO: 54. Most preferably, the transgenic plant of this embodiment comprises a polynucleotide encoding a C-22 sterol desaturase comprising amino acids 1 to 538 of SEQ ID NO: 52 and amino acids 1 to 513 of SEQ ID NO: 54.

The invention also provides a seed that is genetically pure in line for the expression cassettes (also referred to herein as "transgenes") described herein, wherein the transgenic plants grown from said seed show higher yield, as compared to a variety wild type of the plant. The invention also provides a product produced by or from the transgenic plants expressing the polynucleotide, the parts of the plant or their seeds. The product can be obtained by various methods known in the art. As used in the present, the term "product" includes, without limitation, food products for humans, food products for animals, food supplements for humans, supplements food for animals, fibers, cosmetics or pharmaceutical products. Food products for humans are considered compositions for nutrition or to supplement nutrition. Foodstuffs for animals and food supplements for animals, in particular, are considered foodstuffs. The invention also provides an agricultural product produced by any of the transgenic plants, parts of plants and the seeds of plants. Agricultural products include, without limitation, plant extracts, proteins, amino acids, carbohydrates, fats, oils, polymers, vitamins and the like. | The invention also provides an isolated polynucleotide having a sequence selected from the group consisting of SEQ ID NO: 3; SEQ ID NO: 5; SEQ ID NO: 7; SEQ ID NO: 11; SEQ ID NO: 13; SEQ ID NO: 21; SEQ ID NO: 23; SEQ ID NO: 25; SEQ ID NO: 27; SEQ ID NO: 29; SEQ ID NO: 31; SEQ ID NO: 33; SEQ ID NO: 35; SEQ ID NO: 37; SEQ ID NO: 39; SEQ ID NO: 41; SEQ ID NO: 43; SEQ ID NO: 49; and SEQ ID NO: 53. The isolated polynucleotide of the invention also includes an isolated polynucleotide that encodes a polypeptide having an amino acid sequence selected from the group. consisting of SEQ ID NO: 4; SEQ ID NO: 6; SEQ ID NO: 8; SEQ ID NO: 12; SEQ ID NQ: 14; SEQ ID NO: 22; SEQ ID NO: 24; SEQ ID NO: 26; SEQ ID NO: 28; SEQ ID NO: 30; SEQ ID NO: 32; SEQ ID NO: 34; SEQ ID NO: 36; SEQ ID NO: 38; SEQ ID NO: 40; SEQ ID NQ: 42; SEQ ID NO: 44; SEQ ID NO: 50; and SEQ ID NO: 54. A polynucleotide of the invention can be isolated with standard molecular biology techniques and the sequence information provided herein, for example, with an automated DNA synthesizer. , The isolated polynucleotides of the invention include homologs of the polynucleotides of Table 1. In the present, "homologs" are defined as two nucleic acids or polypeptides having similar or substantially identical nucleotide or amino acid sequences, respectively. Homologs include allelic variants, analogs and orthologs, as defined below. As used herein, the term "analogs" refers to two nucleic acids that have the same or similar function, but evolved separately in unrelated organisms. As used herein, the term "orthologs" refers to two nucleic acids from different species, but which evolved from an ancestral gene in common by speciation! The term "homologous" also comprises nucleic acid molecules that differ from one of the nucleotide sequences indicated in Table 1 due to the degeneracy of the genetic code and, therefore, encode the same polypeptide.

To determine the percentage of sequence identity of two sequences of ! amino acids (for example, one of the polypeptide sequences of Table 1 and an homologous to these), the sequences are aligned for purposes of optimal comparison (for example, gaps in the sequence of a polypeptide can be introduced for optimal alignment with the other polypeptide or nucleic acid). The amino acid residues are then compared at the corresponding amino acid positions. When a position in a sequence is occupied by the same amino acid residue as the corresponding position in the other sequence, then the molecules are identical in that position. The same type of comparison can be made between two nucleic acid sequences.

Preferably, homologs, analogs and orthologs of amino acids isolated from the polypeptides of the present invention are at least about 50-60%, preferably at least about 60-70% and, more preferably, at least about 70- 75%, 75-80%, 80-85%, 85-90% or 90-95% and, most preferably, at least about 96%, 97%, 98%, 99% or more identical to a sequence of complete amino acid identified in Table 1. In another preferred embodiment, an isolated nucleic acid homolog of the invention comprises a nucleotide sequence that is at least about 40-60%, preferably at least about 60-70% , more preferably, at least about 70-75%, 75-80%, 80-85%, 85-90% or 90-95% and even more preferably, at least about 95%, 96%, 97 %, 98%, 99% or more identical to a nucleotide sequence indicated in Table 1.

For the purposes of the invention, the percentage of sequence identity between two nucleic acid sequences or polypeptides is determined by the use of Align 2.0 (yers and Miller, CABIOS (1989) 4: 11-17) with the parameters established in the default configurations or the Vector NTI 9.0 (PC) software package (Invitrogen, 1600 Faraday Ave., Carlsbad, CA92008). For the identity percentage calculated with Vector NTI, a gap opening penalty of 15 and a gap extension penalty of 6.66 is used to determine the percent identity of two nucleic acids. A breach penalty of 10 and a gap extension penalty of 0.1 are used to determine the identity percentage of two polypeptides. All other parameters are set as default settings. For the purposes of a multiple alignment (Clustal W algorithm), the breach gap penalty is 10 and the gap extension penalty is 0.05 with matrix blosum62. It must be taken into account that for the purpose of determining the sequence identity when a sequence is compared of DNA with an RNA sequence, a thymidine nucleotide is equivalent to a uracil nucleotide.

The nucleic acid molecules corresponding to homologs, analogs and orthologs of the polypeptides listed in Table 1 can be isolated on the basis of their identity with said polypeptides, by using polynucleotides that encode the respective polypeptides or primers based thereon, as hybridization probes according to standard hybridization techniques under stringent hybridization conditions. As used herein with respect to DNA hybridization in a DNA blot, the term "stringent conditions" refers to hybridization overnight at 60 ° C in Denhart 10X solution, 6X SSC, 0.5 % of SDS and 100 μg / ml denatured salmon sperm DNA.The blots are washed sequentially at 62 ° C for 30 minutes each time 3X SSC / 0.1% SDS, followed by 1X SSC / 0.1% SDS and, finally, 0.1X SSC / 0.1% SDS. As also used herein, in a preferred embodiment, the phrase "stringent conditions" refers to hybridization in a 6X SSC solution at 65 ° C. In another embodiment, "highly stringent conditions" refers to hybridization overnight at 65 ° C in Denhart 10X solution, 6X SSC, 0.5% SDS and 100 μg / ml denatured salmon sperm DNA. . The blots are washed sequentially at 65 ^ for 30 minutes each time in 3X SSC / 0.1% SDS, followed by 1X SSC / 0.1% SDS and finally 0.1X SSC / 0.1% SDS . Methods for performing nucleic acid hybridizations are known in the art.

The isolated polynucleotides used in the invention can be optimized, that is, they can be modified by genetic engineering, to increase their expression in a given plant or animal.To provide optimized plant nucleic acids, the DNA sequence of the invention can be modified. gene so that it: 1) comprises preferred codons for highly expressed plant genes, 2) comprises an A + T content in a nucleotide base composition to which it is substantially in plants, 3) forms a plant initiation sequence; 4) eliminate sequences that cause destabilization, inadequate polyadenylation, RNA degradation and termination, or form secondary structure hairpins or RNA splicing sites, or 5) eliminate antisense open reading frames Increased expression of nucleic acids in plants It can be achieved by using the distribution frequency of codon usage in plants in general or in a particular plant. methods to optimize the expression of nucleic acids in plants can be found in EPA 0359472; EPA 0385962; PCT application No. WO 91/16432; expression cassette selected from the group consisting of: a) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length galactosidase polypeptide; b) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; and an isolated polynucleotide encoding a full length transaldolase A polypeptide; c) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; and an isolated polynucleotide encoding a full-length accessory hydrogenase-2 polypeptide; d) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide that encodes a transit peptide to mitochondria; and an isolated polynucleotide encoding a full length isocitrate Nasa polypeptide; e) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length phospholipid hydroperoxide polypeptide glutathione peroxidase; f) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; and an isolated polynucleotide encoding a full-length gamma-glutamyltranspeptidase polypeptide; g) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide that encodes a transit peptide to mitochondria; and an isolated polynucleotide encoding a polypeptide of the B 'subunit of full-length ATP synthase; and h) an expression cassette comprising, in operative association, an isolated polynucleotide encoding a promoter; an isolated polynucleotide encoding a chloroplast transit peptide; and an isolated polynucleotide encoding a full length C-22 polypeptide esteral desaturase.; In another embodiment, the recombinant expression vector of the invention comprises an isolated polynucleotide having a sequence selected from the group consisting of SEQ ID NO: 3; SEQ ID NO: 5; SEQ ID NO: 7; SEQ ID NO: 11; SEQ ID NO: 13; SEQ ID NO: 21; SEQ ID NO: 23; SEQ ID NO: 25; SEQ ID NO: 27; SEQ ID NO: 29; SEQ ID NO: 31; SEQ ID NO: 33; SEQ ID NO: 35; SEQ ID NO: 37; SEQ ID NO: 39; SEQ ID NO: 41; SEQ ID NO: 43; SEQ ID NO: 49; and SEQ ID NO: 53. Likewise, the recombinant expression vector of the invention comprises an isolated polynucleotide encoding a polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 4; SEQ ID NO: 6; SEQ ID NO: 8; SEQ ID NO: 12; SEQ ID NO: 14; SEQ ID NO: 22; SEQ ID NO: 24; SEQ ID NO: 26; SEQ ID NO: 28; SEQ ID NO: 30; SEQ ID NO: 32; SEQ ID NO: 34; SEQ ID NO: 36; SEQ ID NO: 38; SEQ ID NO: 40; SEQ ID NO: 42; SEQ ID NO: 44; SEQ ID NO: 50; and SEQ ID NO: 54.

The recombinant expression vector of the invention also includes one or more regulatory sequences, selected on the basis of the host cells to be used for expression, which are in operative association with the isolated polynucleotide to be expressed. As used herein with respect to the recombinant expression vector, "in operative association" or "operatively linked" means that the polynucleotide of interest is ligated to the regulatory sequences in a manner that allows expression of the polynucleotide when the vector is introduced. in the host cell (e.g., in a plant or bacterial host cell). The term "regulatory sequence" is intended to include promoters, enhancers and other expression control elements (e.g., polyadenylation signals).

As indicated above, certain embodiments of the invention use promoters that are capable of enhancing gene expression in the leaves. In some embodiments, the promoter is a leaf specific promoter. Any specific leaf promoter can be used in these embodiments of the invention. Many such promoters are known, for example, the USP promoter from Vicia faba (Baeumlein et al (1991) Mol.Gen. Genet 225, 459-67), promoters of light-inducible genes, such as ribulose-1. , 5-bisphosphate carboxylase (rbcS promoters), promoters of genes encoding chlorophyll a / b binding proteins (Cab), Rubisco activase, chloroplast glyceraldehyde 3-phosphate dehydrogenase B subunit of A. thaliana, (Kwon et al. (1994) Plant Physiol. i 105,357-67) and other leaf-specific promoters, such as those identified in German, I. (2001) Isolation and characterization of leaf-specific promoters from alfalfa (Medicago sativa), Masters thesis, New Mexico State University, Los Cruces , Nl) l.

In other embodiments, a specific or root-specific promoter is used. For example, the Superpromotor provides a high level of expression both in the roots as in the outbreaks (Ni et al. (1995) Plant J. 7: 661-676). Other root specific promoters include, without limitation, the TobRB7 promoter (Yamamoto et al. (1991) Plant Cell 3, 371-382), the roID promoter (Leach et al. (1991) Plant Science 79, 69-76); the domain of CaMV 35S (Benfey et al (1989) Science 244, 174-181) and the like.

In other embodiments, a constitutive promoter is used. Constitutive promoters are active under most conditions. Examples of suitable constitutive promoters for use in these embodiments include the ubiquitin promoter of parsley, described in WO2003 / 102198; the CaMV 19S and 35S promoters, the sX CaMV 35S promoter, the Sep1 promoter, the rice actin promoter, the Arabidopsis actin promoter, the maize ubiquitin promoter, pEmu, the 35S promoter of the fig mosaic virus, the Smas promoter , the superpromotor (U.S. Patent No. 5,955,646), the GRP1-8 promoter, the cinnamyl alcohol dehydrogenase promoter (U.S. Patent No. 5,683,439), Agrobacterium T-DNA promoters, such as mannopin synthase, nopaline synthase and octopine synthase, the promoter of the small subunit of ribulose bisphosphate carboxylase (ssuRUBISCO) and the like. i According to the invention, a chloroplast transit sequence refers to a nucleotide sequence that encodes a chloroplast transit peptide. Examples of a chloroplast transit peptide include the group consisting of transit peptide to chlorophyll a / b binding protein, transit peptide to the small subunit of ribulose bisphosphate carboxylase, transit peptide to EPSPS and transit peptide to dihydrodipocholic acid synthase. As defined herein, a mitochondria transit sequence refers to a nucleotide sequence that encodes a mitochondrial presequence and directs the protein to the mitochondria. Examples of pres- sures of mitochondria include groups consisting of ATPase subunits, ATP synthase subunits, Rieske-FeS protein, Hsp60, malate dehydrogenase, citrate synthase, aconitase, isocitrate dehydrogenase, pyruvate dehydrogenase, malic enzyme, glycine decarboxylase, serine hydroxymethyl transferase and superoxide dismutase.

These transit peptides are known in the art. See, for example, Von Heijne et al. (1991) Plant Mol. Biol. Rep. 9: 104-126; Clark et al. (1989) J. Biol. Cherri. 264: 17544-17550; Della-Cioppa et al. (1987) Plant Physiol. 84: 965-968; Romer et al. (1993) Biochem. Biophys. Res. Commun. 196: 1414-1421; and Shah et al. (1986) Science 233: 478-481. Chloroplast targeting sequences are known in the art and include the small subunit of ribulose 1, 5-bisphosphate carboxylase (Rubisco) of chloroplast (de Castro i Silva Filho et al. (1996) Plant Mol. Biol. 30: 769-780; Schnell et al. (1991) J. Biol. Chem. 266 (5): 3335-3342); 5- (enolpiruvil) shiquimato-3-phosphate synthase (EPSPS) (Archer et al (1990) J. Bioenerg, Biomemb.22 (6): 789-810); tryptophan synthase (Zhao et al (1995) J. Biol. Chem. 270 (11): 6081-6087); plastocyanin (Lawrence et al (1997) J. Biol. Chem. 272 (33): 20357-20363); corismate synthase (Schmidt et al (1993) J. Biol. Chem. 268 (36): 2744 | -27457); and the light harvesting chlorophyll a / b binding protein (LHBP) (Lamppa et al (1988) J. Biol. Chem. 263: 14996-14999). See also Von Heijne et al. (1991) Plant Mol. Biol. Rep. 9: 104-126; Clark et al. (1989) J. Biol. Chem. 264: 17544-17550; Della-Cioppa, et al. (1987) Plant Physiol. 84: 965-968; Romer et al. (1993) Biochem. Biophys. Res. Commun. 196: 1414-1421; and Shah et al. (1986) Science 233: 478-481.

In a preferred embodiment of the present invention, the pplinucleotides listed in Table 1 are expressed in plant cells of higher plants (e.g., spermatophytes, such as crop plants). A polynucleotide can be "introduced" into a plant cell by any means, including transfection, transformation or transduction, electroporation, particle bombardment, agroinfection and the like. Suitable methods for transforming or transfecting plant cells are described, for example, by particle bombardment, as set forth in U.S. Patent Nos. 4,945,050; 5,036,006; 5,100,792; 5,302,523; 5,464,765; 5,120,657; 6,084,154; and similar. More preferably, the transgenic maize seed of the invention can be obtained by transformation of Agrobacterium, as described in U.S. Patent Nos. 5,591,616; 5,731,179; 5,981,840; 5,990,387; 6,162,965; 6,420,630, publication of the US patent application No. 2002/0104132 and the like. The soybean transformation can be carried out, for example, with any of the techniques described in European Patent No. EP 0424047, US Patent No. 5,322,783, European Patent No. EP 0397 687, US Patent No. 5,376. 543 oi U.S. Patent No. 5,169,770. A specific example of transformation into wheat can be found in PCT Application No. WO 93/07256. The cotton can be transformed with the methods described in U.S. Patent Nos. 5,004,863; 5,159,135, 5,846,797 and the like. The rice can be transformed with the methods described in U.S. Patent Nos. 4,666,844; 5,350,688; 6,153,813; 6,333,440; 6,288,312; 6,365,807; 6,329,571 and the like. The canola can be transformed, for example, with methods such as those described in U.S. Patent Nos. 5,188,958; 5,463,174; 5,750,871; EP1566443; WO02 / 00900; and similar. Other methods for the transformation of plants are described, for example, in U.S. Patent Nos. 5,932,782; 6,153,811; 6,140,553; 5,969,213; 6,020,539 and the like. In accordance with the invention, any suitable plant transformation method can be used to insert a transgene in a particular plant.

According to the present invention, the introduced polynucleotide can be maintained stably in the plant cell, if it is incorporated into a non-chromosomal autonomous replicon or integrated into the plant chromosomes. Alternatively, the introduced polynucleotide may be present in a non-replicating extrachromosomal vector and may be expressed or active transiently. | The invention also comprises a method for producing a transgenic plant comprising at least one polynucleotide listed in Table 1, wherein expression of the polynucleotide in the plants results in increased growth and / or yield of the plant under normal or limiting conditions. water and / or greater tolerance to environmental stress, compared to a variety of wild type of the plant that comprises the following stages: (a) introducing into a plant cell a cassette of expression described above, (b) regenerating a transgenic plant of the transformed plant cell; and select plants with higher yield of regenerated plant cells. The plant cell can be, without limitation, a protoplast, a cell that produces gametes and a cell that regenerates into a whole plant. As used herein, the term "transgenic" refers to any plant, plant cell, callus, plant tissue or part of the plant that contains the expression cassette described above. According to the invention, the expression cassette is stably integrated into a chromosome or stable extrachromosomal element, so that it is transmitted to successive generations The effect of the genetic modification on the growth and / or yield and / or tolerance to stress of the plant can be evaluated by cultivating the modified plant under normal and / or less than adequate conditions, and then analyzing the growth characteristics and / or the metabolism of the plant. Said analytical techniques are known to those skilled in the art, and include measures of dry weight, wet weight, seed weight, number of seeds, polypeptide synthesis, carbohydrate synthesis, lipid synthesis, evapotranspiration rates, general performance of plant and / or culture, flowering, reproduction, seed settling, root growth, respiration rates, photosynthesis rates, composition of metabolites and the like.

The invention is also illustrated by the following examples, which should not be construed as limiting the scope of the present.

EXAMPLE 1 Characterization of genes The guide genes b0757 (SEQ ID NO: 1), b2464 (SEQ ID NO: 9), b2990 (SEQ ID NO: 15), SLL1323 (SEQ ID NO: 47), slr1269 (SEQ ID NO: 45), YER065C ( SEQ ID NO: 17), YIR037W (SEQ ID NO: 19) and YMR015C (SEQ ID NO: 51) were cloned by standard recombination techniques. The functionality of each guideline was predicted by comparing the amino acid sequence encoded by the gene with other genes of known functionality. Homologous cDNAs were isolated from registered libraries of the respective species by the use of known methods. The sequences were processed and scored by bioinformatic analysis.

The gene b0757 (SEQ ID NO: 1) of E. coli encodes a galactokinase. The full-length amino acid sequence of b0757 (SEQ ID NO: 2) was subjected to blast against a registered cDNA database with an e-value of 10 (Altschul et aj., Supra). soybean and a corn homologue The relationship between the amino acids of these sequences is indicated in the alignments of Figure 1.

The b2464 gene (SEQ ID NO: 9) of E. coli encodes transaldolase A. The full length amino acid sequence of b2464 (SEQ ID NO: 10) was subjected to blast against a registered cDNA database with an e-value. of e "10 (Altschul et al., supra.) A homolog of canola and a soybean homologue were identified.The relationship between the amino acids of these sequences is indicated in the alignments of Figure 2.

The YIR037W gene (SEQ ID NO: 19) of S. cerevisiae encodes a phospholipid hydroperoxide glutathione peroxidase. The full-length amino acid sequence of YIR037W (SEQ ID NO: 20) was subjected to blast against a registered cDNA database with an e-value of 10 (Altschul et al., Supra). The soybean homologues, a sunflower homologue, a barley homologue, a rice homologue, and two corn homologues are indicated by the amino acids in these sequences, indicated by the alignments in Figure 3.

The SLL1323 gene (SEQ ID NO: 47) of Synechocystis sp. encodes the B 'subunit of ATP synthase. The full-length amino acid sequence of SLL1323 (SEQ ID NO: 48) was subjected to blast against a registered cDNA database with an e-value of 10.

(Altschul et al., Supra). A soybean homolog was identified. The relationship between the amino acids of these sequences is indicated in the alignments of Figure 4.

The gene YMR015C (SEQ ID NO: 51) of S. cerevisiae encodes a C-22 esteral desaturase. The full-length amino acid sequence of YMR015C SEQ ID NO. 52) was subjected to blast against a registered cDNA database with an e-value of 0 (Altschul et al., Supra.) A soy homolog was identified.The relationship between the amino acids of these sequences is indicated in the alignments of Figure 5.

EXAMPLE 2 Overexpression of guide genes in plants The polynucleotides of Table 1 were ligated into an expression cassette by known methods. Three different promoters were used to control the expression of the transgenes in Arabidopsis: the USP promoter ("USP") from Vicia faba (SEQ ID ?? 61 or SEQ ID NO: 62); the superpromotor ("Super"; SEQ ID NO: 63); and the ubiquitin promoter of parsley ("PCUbi"; SEQ ID NO: 64). For directed expression, a transit peptide to mitochondria (SEQ ID NO: 56 or SEQ ID NO: 58, termed "Myth" in Tables 2-9) or a chloroplast transit peptide (SEQ ID NO: 60) was used. designated "Plástido" in Tables 2-10).

The C24 ecotype of Arabidopsis was transformed with constructs containing the guide genes described in Example 1 by known methods. The seeds of the transformed T2 plants were grouped on the basis of the promoter that directed the expression, the species of source genes and the type of targeting (chloroplast, mitochondrion or without targeting). The seed pools were used in the primary sweeps of biomass, under conditions of growth with abundant water and in conditions of limited water growth. The coincidences of the pools were selected in the primary scan, a molecular analysis was carried out and the seeds were collected. Then the seeds were used; collected for the analysis of the secondary sweeps, where a greater number of individuals was analyzed for each transgenic event. If plants of a higher biomass construct were identified in the secondary scan, compared to the controls, they passed to the tertiary sweep. In this sweep, more than 100 plants of all transgenic events were measured for that construct, under growing conditions with abundant water and growing conditions with drought. Data from the transgenic plants were compared with wild-type Arabidopsis plants or with plants grown from a pool of randomly selected transgenic Arabidopsis seeds by the use of statistical procedures standard.

The plants that were cultivated in abundant water conditions were irrigated until the saturation of the soil twice a week. Images were taken of (the transgenic plants on days 17 and 21 by a commercial imaging system.) Alternatively, the plants were grown under limited water growth conditions by watering infrequently until the soil was saturated, which allowed The soil was dried between the water treatments In these experiments, water was supplied on days 0, 8, and 19 after sowing Images of the transgenic plants were taken on days 20 and 27 by a commercial imaging system. Í The image analysis software was used to compare images of transgenic plants and control plants grown in the same experiment. The images were used to determine the biomass or the relative size of the plants as pixels and the color of the plants as the relationship between the dark green area and the total area. The latter ratio, called the health index, was measured from the relative amount of chlorophyll in the leaves and, therefore, the relative amount of senescence or yellowing of the leaves and was recorded only on day 27. The variation exists between transgenic plants which contain the various guide genes, due to different sites of DNA insertion and other factors that impact on the level or pattern of gene expression. To show this effect, the data tables indicate the number of plants that were positive and negative for the trait.

Tables 2 to 9 show the comparison of the measurements of the plants of Arabidopsis "CD" indicates that the plants were grown under conditions of drought cycles; "WW" indicates conditions of abundant water. A number after an abbreviation indicates multiple independent experiments under the same conditions. The percentage of change indicates the measurement of the transgenic plants with respect to the control plants, as a percentage of the non-transgenic control plants; the p value is the statistical significance of the difference between the control plants and the transgenic plants on the basis of a comparison of the T test of all the independent events, where NS indicates non-significant with a probability level of 5%; No. of events indicates the total number of independent transgenic events evaluated in the experiment; No. of positive events indicates the total number of independent transgenic events that were greater than the control in the experiment; No. of negative events indicates the total number of independent transgenic events that were less than the control in the experiment.

A. Galactoquinasa j The galactokinase b0757 gene (SEQ ID NO: 1) was expressed in Arabidopsis under the control of the Superpromotor directed to the chloroplast. Table 2 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated in conditions of abundant water and drought cycles. i Table 2 Table 2 shows that Arabidopsis plants expressing the b0757 gene directed to the chloroplast resulted in larger plants under water limiting conditions, but not under abundant water conditions. In these experiments, all the independent transgenic events expressing the b0757 gene were larger than the controls, indicating a better adaptation to environmental stress.

B. Transaldolase A The b2464 gene of transaldolase A (SEQ ID NO: 9) was expressed in Arabidopsis under the control of the USP or Superpromotor promoter without subcellular targeting. Table 3 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated in conditions of abundant water and drought cycles.

Table 3 Table 3 shows that Arabidopsis plants expressing the b2464 gene under Superpromotor control were larger under water limiting conditions. The variation exists between transgenic plants that contain the b2464 gene, due to different sites of DNA insertion and other factors that impact on the level or pattern of gene expression. In these experiments, most of the independent transgenic events expressing the b2464 gene were larger than the controls, indicating a better adaptation to environmental stress. In addition, expression of the b2464 gene under the control of the USP promoter resulted in larger plants in conditions of abundant water. i In these experiments, all the transgenic events expressing the | b2464 gene were larger than the controls.

C. Hydrogenase-2 accessory protein The b2990 gene of the accessory protein of hydrogenase-2 (SEQ ID NO: 1 | 5) was expressed in Arabidopsis under the control of the Superpromotor without subcellular targeting. Table 4 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated in conditions of abundant] water and drought cycles.

Table 4 Table 4 shows that the Arabidopsis plants expressing the b2990 gene were larger in conditions of abundant water and in water-limiting conditions. The variation exists between transgenic plants that contain the b2990 gene, due to different DNA insertion sites and other factors that impact the p-level pattern of gene expression. In these experiments, most of the independent transgenic events j that expressed the b2990 gene were larger than the controls, indicating a better adaptation to environmental stress. In conditions of abundant water, the expression of the b2990 gene resulted in plants with a lower health index; this effect was not observed in water limiting conditions. ! D. Isocitrato Mass The YER065C gene of isocitrate lyase (SEQ ID NO: 17) was expressed in Arabidopsis under the control of the USP promoter without subcellular targeting. Table 5 shows the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated under abundant water conditions.

Table 5 Table 5 shows that the Arabidopsis plants expressing the YER065C gene were larger under abundant water conditions. The variation exists between transgenic plants that contain the YER065C gene, due to different sites of DNA insertion and other factors that impact on the level or pattern of gene expression. In these experiments, the majority of the independent transgenic events expressing the YER065C gene were larger than the controls.

| E. Phospholipid hydroperoxide glutathione peroxidase The YIR037W gene of phospholipid hydroperoxide glutathione peroxidase (SEQ ID NO: 19) was expressed in Arabidopsis under the control of the USP or PCUbi promoter directed to the chloroplast or to the mitochondria. Table 6 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated under conditions of abundant water and in water limiting conditions.

Table 6 Gen Type Promoter White Trait Percentage Value Events Events Events of change? valid negative positive essay WW YIR037 PCUbi Plastid Biomass 4.9 NS 6 4; 2 W on Day 17 WW YIR037 PCUbi Plaster Biomass -1, 8 NS 6 3 3 W on Day 21 WW YIR037 PCUbi Plastid Index of 11, 3 0.006 6 6 0 W health ww YIR037 USP Biomass plastid -12.1 0.003 6 1 5 W on Day 17 ww YIR037 USP Biomass plastid -8.1 0.017 6 1 5 W on Day 21 ww YIR037 USP Plástido Index of -7.5 0.000 6 0 6 W health CD YIR037 PCUbi Biomass plastid 12.2 0.004 6 5: 1 W on Day 20 CD YIR037 PCUbi Biomass plaster 11.2 0.000 6 6 0 W on Day 27 CD YIR037 PCUbi Plastid index 10.2 0.011 6 5 1 W health CD YIR037 USP Myth Biomass -6.1 NS 6 2 4 W on Day 20 CD YIR037 USP Myth Biomass -6.0 NS 6 1 5 W on Day 27 CD YIR037 USP Myth Index of 1, 2 NS 6 4 2 W health CD YIR037 USP Biomass plastid -7.9 0.015 6 5 W on Day 20 1! CD YIR037 USP Biomass plastid -8.9 0.007 6 o; 6 W on Day 27 CD YIR037 USP Plastid Index of -1, 0 NS 6 1 5 W health Table 6 shows that the Arabidopsis plants expressing the YIR037W gene controlled by the PCUbi promoter and directed to the chloroplast were larger than the controls under water limiting conditions, indicating a better adaptation to environmental stress. In addition, the transgenic plants that expressed YIR037W had a darker green color than the controls under conditions of abundant water and in water-limiting conditions, as indicated by the increase in the health index. This suggests that transgenic plants expressing YIR037W produced more chlorophyll or had less chlorophyll degradation, compared to control plants.

When expression of YIR037W gene was controlled by the USP promoter and chloroplast targeted, transgenic plants expressing YIR037W were smaller than control plants under conditions of large amounts of water and water-limiting conditions. Likewise, the transgenic plants that expressed YIR037W had a less green color than the control plants under abundant water conditions, as indicated by the decrease in the health index. This suggests that transgenic plants expressing YIR037W with this specific construct produced less chlorophyll or had more chlorophyll degradation, compared to control plants. If the target of the YIR037W gene was the mitochondria under the control of the USP promoter, no difference was observed significant in the biomass or health index, when the transgenic plants that expressed YIR037W were compared with the control plants.

F. Gama-glutamyltranspeptidase The slr1269 gene glutamyl range (SEQ ID NO: 45) was expressed in Arabidopsis under control of the promoter pCUBI directed to the chloroplast, the mito'condria or without subcellular targeting. Table 7 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated in conditions of abundant water or drought cycles.

Table 7 CD slr1269 PCUbi Biomass plastid -6.8 0.018 5 2 3 on Day 27 CD slr1269 PCUbi Plástido Index of -1,9 NS 5 2; 3 I Health Table 7 shows that the Arabidopsis plants that expressed the srl1269 gene directed to mitochondria were smaller than controls in water-limiting conditions. Likewise, the transgenic plants that expressed srl1269 had a less green color than the control plants in conditions of abundant water and in water-limiting conditions, as indicated by the decrease in the health index. This suggests that transgenic plants expressing srl1269 directed to the mitochondria produced less chlorophyll or had a greater degradation of chlorophyll, compared with plants i control. Similar results were observed when the expression of the slr1269 gene was directed to the chloroplast. Under water-limiting conditions, the transgenic plants expressing slr1269 were smaller than the controls. Under conditions of abundant water, the transgenic plants that expressed srl1269 had a less green color than the controls, as indicated by the decrease in the health index.

When slr1269 gene expression had no subcellular targeting, transgenic plants expressing slr1269 were larger than control plants in water limiting conditions, indicating better adaptation to environmental stress. In addition, the transgenic plants that expressed srl1269 had a darker green color than the controls under water limiting conditions, as indicated by the increase in the health index. This suggests that transgenic plants that expressed srl1269 produced more chlorophyll or had less degradation of chlorophyll, compared to control plants.

G. Subunit B 'of ATP synthase The SLL1323 gene of the B 'subunit of ATP synthase (SEQ ID NO: 47) was expressed in Arabidopsis under the control of the PCUbi promoter directed to the mitochondria. Table 8 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated in conditions of abundant water or drought cycles.

Table 8 Table 8 shows that Arabidopsis plants expressing the SLL1323 gene resulted in larger plants in conditions of abundant water and in water-limiting conditions. The variation exists between transgenic plants that contain the SLL1323 gene, due to different sites of DNA insertion and other factors that impact on the level or pattern of gene expression. In these experiments, most of the independent transgenic events that expressed the sIM 323 gene were larger than the controls, indicating a better adaptation to environmental stress. In addition, transgenic plants expressing SLL1323 had a darker green color than controls under water-limiting conditions, as indicated by the increase in health index. This suggests that the plants produced more chlorophyll or had less chlorophyll degradation during stress, compared to the control plants.

H. C-22 sterol desaturase The YMR015C gene (SEQ ID NO: 51), which encodes C-22 sterol desaturase, was expressed and directed to the chloroplast in Arabidopsis by the use of three constructs. In one, the transcription is controlled by the PCUbi promoter. In another, the transcription is controlled by the Superpromotor. In the third construct, the transcription of YMR015C is controlled by the USP promoter. Table 9 indicates the biomass and health index data obtained from Arabidopsis plants transformed with these constructs and evaluated under conditions of abundant water and in water limiting conditions.

Table 9 I Table 9 shows that the Arabidopsis plants with the PCUbi promoter that controlled the expression of YMR015C were significantly larger than the control plants, when the protein was also directed to the chloroplast. In addition, these transgenic plants and those with the Superpromotor that controlled the expression of Y R015C were darker green than the controls. These data indicate that the plants produced more chlorophyll or had less chlorophyll degradation during stress, compared to the control plants. Table 9 also shows that most of the independent transgenic events were larger than the controls.

Table 9 shows that the Arabidopsis plants grown under abundant water conditions with the PCUbi promoter or with the Superpromotor that controlled the expression of YMR015C were significantly smaller than the control plants, when the protein was also directed to the chloroplast. Table 9 also shows that most of the Independent transgenic events were smaller than the controls. In addition, both constructs significantly reduced the amount of green color of the plants, when they were grown under abundant water conditions.

Claims

I i CLAIMS

1. A transgenic plant transformed with an expression cassette, characterized in that it comprises, in operative association, a) an isolated polynucleotide encoding a promoter capable of enhancing gene expression in leaves; b) an isolated polynucleotide encoding a transit peptide to mitochondria; Y c) an isolated polynucleotide encoding a full length isocitrate Nasa polypeptide comprising amino acids 22 to 550 of SEQ ID NO: 18, wherein the transgenic plant shows higher yield, as compared to a wild type plant of the same variety as does not understand the expression cassette. j

2. A seed that is genetically pure line for a transgene characterized because it comprises, in operative association, a) an isolated polynucleotide encoding a promoter capable of enhancing gene expression in leaves; b) an isolated polynucleotide encoding a transit peptide to mitochondria; Y c) an isolated polynucleotide encoding a full-length isocitrate lyase polypeptide comprising amino acids 22 to 550 of SEQ ID NO: 18, wherein the transgenic transgenic plant of said seed shows higher yield, as compared to a wild-type plant of the same variety that does not include the transgene. j

3. A method for increasing the yield of a plant, characterized in that the method comprises the following steps: a) transform a plant cell with a cassette of expression that accomplishes, in operative association, i) an isolated polynucleotide encoding a promoter capable of enhancing gene expression in leaves; ii) an isolated polynucleotide encoding a transit peptide to mitochondria; Y iii) an isolated polynucleotide encoding a full length isocitrate lyase polypeptide comprising amino acids 22 to 550 of SEQ ID NO: 18; b) regenerating transgenic plants of the transformed plant cell; Y c) selecting transgenic plants that show higher yield, as compared to a wild type plant of the same variety that does not comprise the expression cassette.