Plants Having Enhanced Yield-Related Traits and a Method for Making the Same

Abstract

The present invention relates generally to the field of molecular biology and concerns a method for improving various plant growth characteristics by modulating expression in a plant of a nucleic acid encoding a GRP (Growth-Related Protein), specifically a nucleic acid encoding a HAL3 polypeptide, a nucleic acid encoding a MADS15 polypeptide, a nucleic acid encoding a PLT transcription factor polypeptide, a nucleic acid encoding a Squamosa promoter binding protein-like 15 (SPL15) transcription factor polypeptide or a nucleic acid encoding a basic/helix-loop-helix (bHLH) transcription factor. The present invention also concerns plants having modulated expression of a nucleic acid encoding a GRP, which plants have improved growth characteristics relative to corresponding wild type plants or other control plants. The invention also provides constructs useful in the methods of the invention.

1 . A method for enhancing a yield-related trait in a plant relative to a control plant, comprising:
 (a) increasing expression of:
 (i) a nucleic acid encoding a HAL3 polypeptide; 
 (ii) a nucleic acid encoding a MADS15 protein; 
 (iii) a nucleic acid encoding a PLT transcription factor polypeptide; 
 (iv) a nucleic acid encoding an SPL15 transcription factor polypeptide; or 
 (v) a nucleic acid encoding a bHLH transcription factor comprising the amino acid sequence of SEQ ID NO 213, SEQ ID NO 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO 225, SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, or an orthologue or paralogue thereof; 
   (b) selecting for a plant having an enhanced yield-related trait relative to a control plant.   
     
     
         2 . The method of  claim 1 , wherein said increased expression is effected by:
 (a) introducing and expressing in the plant a nucleic acid encoding a HAL3 polypeptide;   (b) introducing and expressing in the plant a nucleic acid encoding a MADS15 protein, wherein said MADS15 protein comprises any one or more of the motifs of SEQ ID NO: 48, SEQ ID NO: 49, SEQ ID NO: 50 and SEQ ID NO: 51;   (c) introducing and expressing in the plant a nucleic acid encoding a PLT transcription factor polypeptide;   (d) introducing and expressing in the plant a nucleic acid encoding a SPL15 transcription factor polypeptide; or   (e) introducing and expressing in the plant a nucleic acid encoding a bHLH transcription factor comprising the amino acid sequence of SEQ ID NO 213, SEQ ID NO 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO 225, SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, or an orthologue or paralogue thereof.   
     
     
         3 . The method of  claim 2 , wherein:
 (a) said nucleic acid encoding a HAL3 protein comprises any one of the nucleic acid SEQ ID NOs given in Table A, or a portion thereof, or a sequence capable of hybridizing with any one of the nucleic acids SEQ ID NOs given in Table A;   (b) said nucleic acid encoding a MADS15 protein comprises any one of the nucleic acid SEQ ID NOs given in Table D, or a portion thereof, or a sequence capable of hybridixing with any one of the nucleic acids SEQ ID NOs given in Table D;   (c) said nucleic acid encoding a PLT transcription factor polypeptide comprises any one of the nucleic acid SEQ ID NOs given in Table I, or a portion thereof, or a sequence capable of hybridizing with any one of the nucleic acids SEQ ID NOs given in Table I;   (d) said nucleic acid encoding a SPL15 transcription factor polypeptide comprises any one of the nucleic acid SEQ ID NOs given in Table N, or a portion thereof, or a sequence capable of hybridizing with any one of the nucleic acids SEQ ID NOs given in Table N; or   (e) said nucleic acid encoding a bHLH transcription factor is a portion of, an allelic variant of, a splice variant of, or a sequence capable of hybridizing to a nucleic acid comprising the nucleotide sequence of SEQ ID NO: 212, SEQ ID NO: 214, SEQ ID NO: 216, SEQ ID NO: 218, SEQ ID NO: 220, SEQ ID NO: 222, SEQ ID NO: 224, SEQ ID NO: 226, SEQ ID NO: 228, SEQ ID NO: 296, SEQ ID NO: 298 or SEQ ID NO: 300, wherein said portion, allelic variant, splice variant or hybridizing sequence encodes a bHLH transcription factor.   
     
     
         4 . The method of  claim 2 , wherein:
 (a) said nucleic acid encoding a HAL3 protein encodes an orthologue or paralogue of any of the polypeptide SEQ ID NOs given in Table A;   (b) said nucleic acid encoding a MADS15 protein encodes an orthologue or paralogue of any of the polypeptide SEQ ID NOs given in Table D;   (c) said nucleic acid encoding a PLT transcription factor encodes an orthologue or paralogue of any of the polypeptide SEQ ID NOs given in Table D;   (d) said nucleic acid encoding a SPL15 transcription factor polypeptide encodes an orthologue or paralogue of any of the polypeptide SEQ ID NOs given in Table N.   
     
     
         5 . The method of  claim 1 , wherein:
 (a) said nucleic acid encodes a HAL3 protein, and wherein said enhanced yield-related trait comprises increased yield and/or early vigour;   (b) said nucleic acid encodes MADS15 protein, and wherein said enhanced yield-related trait comprises root biomass;   (c) said nucleic acid encodes a PLT transcription factor, and wherein said enhanced yield-related trait comprises increased seed yield;   (d) said nucleic acid encodes a SPL15 transcription factor polypeptide, and wherein said enhanced yield-related trait comprises increased seed yield;   (e) said nucleic acid encodes a bHLH transcription factor, and wherein said enhanced yield-related trait comprises early vigour.   
     
     
         6 . The method of  claim 5 , wherein:
 (a) said nucleic acid encodes a HAL3 protein, and wherein said enhanced yield-related trait is increased seed yield comprising increased seed biomass, increased harvest index, and/or increased number of (filled) seeds;   (b) said nucleic acid encodes a PLT transcription factor, and wherein said increased seed yield comprises increased seed biomass, increased number of flowers per plant, increased number of (filled) seeds, increased seed filling rate, increased harvest index, increased Thousand Kernel Weight (TKW), increased seed area, increased seed length, and/or increased seed width;   (c) said nucleic acid encodes a SPL15 transcription factor polypeptide, and wherein said increased seed yield comprises increased aboveground biomass, increased number of flowers per plant, increased seed yield, increased number of (filled) seeds, increased thousand kernel weight (TKW), and/or increased harvest index.   
     
     
         7 . The method of  claim 2 , wherein:
 (a) said nucleic acid encoding a HAL3 protein protein is operably linked to a shoot-specific promoter or a beta expansin promoter;   (b) said nucleic acid encoding a MADS15 protein is operably linked to a constitutive promoter or a GOS2 promoter;   (c) said nucleic acid encoding a PLT transcription factor is operably linked to a constitutive promoter or a GOS2 promoter;   (d) said nucleic acid encoding a SPL15 transcription factor polypeptide is operably linked to a constitutive promoter, a high mobility group B (HMGB) promoter, a GOS2 promoter, a rice HMGB promoter, or a rice GOS2 promoter; or   (e) said nucleic acid encoding a bHLH transcription factor is operably linked to a constitutive promoter or a GOS2 promoter.   
     
     
         8 . The method of  claim 2 , wherein:
 (a) said nucleic acid encoding a HAL3 protein is of plant origin, from a dicotyledonous plant, from the family Brassicaceae, from the genus  Arabidopsis , or from  Arabidopsis thaliana;      (b) said nucleic acid encoding a MADS15 protein is of plant origin, from a monocotyledonous plant, from the family Poaceae, from the genus  Oryza , or from  Oryza sativa;      (c) said nucleic acid encoding a PLT transcription factor is of plant origin, from a dicotyledonous plant, from the Brassicaceae family, from the genus  Arabidopsis , or from  Arabidopsis thaliana;      (d) said nucleic acid encoding a SPL15 transcription factor polypeptide is of plant origin, from a dicotyledonous plant, from the family Brassicaceae, or from  Arabidopsis thaliana ; or   (e) said nucleic acid encoding a bHLH transcription factor is of plant origin, from a monocotyledonous plant, from the family Poaceae, from the genus  Oryza , or from  Oryza sativa.      
     
     
         9 . A plant or part thereof obtained by the method of  claim 1 , or a seed or progeny of said plant, wherein said plant or part thereof, or said seed or progeny, comprises a recombinant nucleic acid encoding a HAL3 polypeptide, a recombinant nucleic acid encoding a MADS15 protein, a recombinant nucleic acid encoding a PLT transcription factor polypeptide operably linked to a constitutive promoter, a recombinant nucleic acid encoding a SPL15 transcription factor polypeptide, or a recombinant nucleic acid encoding a bHLH transcription factor. 
     
     
         10 . A construct comprising:
 (a) (i) a nucleic acid encoding a HAL3 polypeptide
 (ii) a nucleic acid encoding a MADS15 protein comprising one or more of the motifs of SEQ ID NO: 48, SEQ ID NO: 49, SEQ ID NO: 50 and SEQ ID NO: 51; 
 (iii) a nucleic acid encoding a PLT transcription factor polypeptide; 
 (iv) a nucleic acid encoding an SPL15 transcription factor polypeptide; or 
 (v) a nucleic acid encoding a bHLH transcription factor comprising the amino acid sequence of SEQ ID NO 213, SEQ ID NO 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO 225, SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, or an orthologue or paralogue thereof; 
   (b) one or more control sequences capable of driving expression of the nucleic acid of (a) in a plant; and optionally   (c) a transcription termination sequence.   
     
     
         11 . The construct of  claim 10 , wherein:
 (a) said nucleic acid encodes a HAL3 polypeptide, and wherein said one or more control sequences is a shoot-specific promoter or a beta expansin promoter;   (b) said nucleic acid encodes a MADS15 protein, and wherein said one or more control sequences is a constitutive promoter or a GOS2 promoter;   (c) said nucleic acid encodes a PLT transcription factor polypeptide, and wherein said one or more control sequences is a constitutive promoter or a GOS2 promoter;   (d) said nucleic acid encodes a SPL15 transcription factor polypeptide, and wherein said one or more control sequences is a constitutive promoter, a HMGB promoter, or a GOS2 promoter; or   (e) said nucleic acid encodes a bHLH transcription factor, and wherein said one or more control sequences is a constitutive promoter or a GOS2 promoter.   
     
     
         12 . A plant, plant part or plant cell transformed with the construct of  claim 10 . 
     
     
         13 . A plant, plant part or plant cell comprising the construct of  claim 10 . 
     
     
         14 . A method for the production of a transgenic plant having an enhanced yield-related trait relative to a control plant, comprising:
 (a) introducing and increasing expression in a plant of:
 (i) a nucleic acid encoding a HAL3 polypeptide; 
 (ii) a nucleic acid encoding a MADS15 protein comprising one or more of the motifs of SEQ ID NO: 48, SEQ ID NO: 49, SEQ ID NO: 50 and SEQ ID NO: 51; 
 (iii) a nucleic acid encoding a PLT transcription factor polypeptide; 
 (iv) a nucleic acid encoding an SPL15 transcription factor polypeptide; or 
 (v) a nucleic acid encoding a bHLH transcription factor comprising the amino acid sequence of SEQ ID NO 213, SEQ ID NO 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO 225, SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, or an orthologue or paralogue thereof; 
   (b) cultivating the plant under conditions promoting plant growth and development; and   (c) selecting for a plant having an enhanced yield-related trait relative to a control plant.   
     
     
         15 . The method of  claim 14 , further comprising obtaining a seed or progeny of said plant. 
     
     
         16 . A transgenic plant having an enhanced yield-related trait relative to a control plant resulting from increased expression of:
 (i) a nucleic acid encoding a HAL3 polypeptide;   (ii) a nucleic acid encoding a MADS15 protein comprising one or more of the motifs of SEQ ID NO: 48, SEQ ID NO: 49, SEQ ID NO: 50 and SEQ ID NO: 51;   (iii) a nucleic acid encoding a PLT transcription factor polypeptide;   (iv) a nucleic acid encoding an SPL15 transcription factor polypeptide; or   (v) a nucleic acid encoding a bHLH transcription factor comprising the amino acid sequence of SEQ ID NO 213, SEQ ID NO 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO 225, SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, or an orthologue or paralogue thereof,   in said plant, or a transgenic plant cell obtained from said transgenic plant.   
     
     
         17 . The transgenic plant of  claim 16 , wherein said plant is a crop plant, a monocot plant or a cereal, or wherein said plant is rice, maize, wheat, barley, millet, rye, triticale, sorghum or oats. 
     
     
         18 . Harvestable parts of the transgenic plant of  claim 16 . 
     
     
         19 . Products obtained from the transgenic plant of  claim 16  and/or from harvestable parts of said trasngenic plant. 
     
     
         20 . A method for increasing abiotic stress resistance in a plant relative to a control plant, comprising introducing into a plant the construct of  claim 10 , and selecting for a plant having increased abiotic stress resistance relative to a control plant, wherein said nucleic acid encodes a PLT transcription factor polypeptide, and wherein said increased abiotic stress resistance is preferably increased nutrient uptake efficiency. 
     
     
         21 . An isolated polypeptide comprising:
 (a) the amino acid sequence of SEQ ID NO: 297, SEQ ID NO: 299, or SEQ ID NO: 301; or   (b) an amino acid sequence having at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or more sequence identity to the amino acid sequence of SEQ ID NO: 297, SEQ ID NO: 299 or SEQ ID NO: 301, wherein said amino acid sequence further comprises a bHLH domain.   
     
     
         22 . An isolated nucleic acid molecule comprising:
 (a) a nucleic acid sequence encoding the isolated polypeptide of  claim 21 ;   (b) the nucleic acid sequence of SEQ ID NO: 296, SEQ ID NO: 298 or SEQ ID NO: 300; or   (c) the complement of the nucleic acid sequence of SEQ ID NO: 296, SEQ ID NO: 298 or SEQ ID NO: 300.