Plants Having Improved Growth Characteristics And Method For Making The Same

Abstract

The present invention concerns a method for improving growth characteristics of plants by modulating expression of a nucleic acid sequence encoding a NAP1-like protein. The invention also relates to transgenic plants having improved growth characteristics, which plants have modulated expression of a nucleic acid encoding a NAP1-like protein.

1 . A method for improving growth characteristics of a plant relative to corresponding wild type plants, comprising introducing a genetic modification in said plant and selecting for modulated expression in said plant of a nucleic acid sequence encoding a NAP1-like protein. 
     
     
         2 . The method according to  claim 1 , wherein said modulated expression is increased expression. 
     
     
         3 . The method according  claim 1 , wherein said genetic modification is effected by one of site-directed mutagenesis, homologous recombination, TILLING, T-DNA activation and DNA shuffling. 
     
     
         4 . The method according to  claim 1 , wherein said genetic modification comprises introducing an isolated nucleic acid sequence encoding a NAP1-like protein into a plant. 
     
     
         5 . The method according to  claim 4 , wherein said nucleic acid is derived from a plant, preferably from a dicotyledonous plant, more preferably from the family Brassicaceae, most preferably from  Arabidopsis thaliana.    
     
     
         6 . The method according to  claim 4 , wherein said nucleic acid sequence and said proteins include variants chosen from:
 (i) a nucleic acid encoding a NAP1-like protein, wherein the NAP1-like protein is preferably as represented by SEQ ID NO: 1 or encodes a NAP1-like protein as represented by SEQ ID NO: 2;   (ii) an alternative splice variant of a nucleic acid sequence encoding a NAP1-like protein or wherein said NAP1-like protein is encoded by a splice variant;   (iii) an allelic variant of a nucleic acid sequence encoding a NAP1-like protein or wherein said NAP1-like protein is encoded by an allelic variant;   (iv) a sequence capable of hybridising to a NAP1-like encoding nucleic acid, preferably under stringent conditions;   (v) a NAP1-like protein;   (vi) a NAP1-like protein as represented by SEQ ID NO: 2; and   (vii) homologues and derivatives of a NAP1-like protein, preferably of the NAP1-like protein presented in SEQ ID NO:2,   
       and wherein said NAP1-like protein comprises a NAP domain and an acidic C-terminal, and has PP2a phosphatase inhibiting activity. 
     
     
         7 . The method according to  claim 1 , wherein said improved growth characteristics is increased yield, preferably increased seed yield. 
     
     
         8 . The method according to  claim 7 , wherein said increased seed yield comprises one or more of increased number of filled seeds, increased total weight of seeds or increased Harvest Index, each relative to corresponding wild type plants. 
     
     
         9 . The method according to  claim 4 , wherein said nucleic acid encoding a NAP1-like protein is operably linked to a constitutive promoter, preferably a GOS2 promoter. 
     
     
         10 . A method for production of a transgenic plant having increased yield, which method comprises:
 (i) introducing into a plant cell a nucleic acid sequence encoding a NAP1-like protein; and   (ii) regenerating and/or growing a plant from the transgenic plant cell.   
     
     
         11 . Plants with increased yield obtainable by the method according to  claim 1 , including harvestable parts, propagules, seeds or progeny thereof, and including products directly derived thereof. 
     
     
         12 . A gene construct for expression in a plant, comprising:
 (i) a nucleic acid sequence encoding a NAP1-like protein;   (ii) one or more control sequences capable of driving expression in a plant of the nucleic acid sequence of (i); and optionally   (iii) a transcription termination sequence.   
     
     
         13 . The gene construct according to  claim 12 , wherein said nucleic acid encoding a NAP1-like protein is chosen from the group comprising:
 a nucleic acid sequence represented by SEQ ID NO: 1 or the complement strand thereof;   (ii) a nucleic acid sequence encoding an amino acid sequence represented by SEQ ID NO: 2 or homologues, derivatives or active fragments thereof;   (iii) a nucleic acid sequence capable of hybridising (preferably under stringent conditions) with a nucleic acid sequence of (i) or (ii) above, which hybridising sequence preferably encodes a protein having NAP1-like protein activity;   (iv) a nucleic acid sequence according to (i) to (iii) above which is degenerate as a results of the genetic code;   (v) nucleic acid sequence which is an allelic variant to the nucleic acid sequences according to (i) to (iii); and   (vi) nucleic acid sequence which is an alternative splice variant to the nucleic acid sequences according to (i) to (iii),   
       and wherein said NAP1-like protein comprises a NAP domain and an acidic C-terminal, and has PP2a phosphatase inhibiting activity. 
     
     
         14 . The gene construct according to  claim 12 , wherein said control sequences comprise at least a constitutive promoter, preferably a GOS2 promoter. 
     
     
         15 . The gene construct according to  claim 12 , wherein said nucleic acid sequence encoding a NAP1-like protein is oriented in sense direction relative to said control sequence. 
     
     
         16 . A construct comprising an expression cassette essentially similar to SEQ ID NO: 3. 
     
     
         17 . A transgenic plant comprising an isolated nucleic acid sequence encoding a NAP1-like protein, characterized in that said plant has been selected for having increased yield. 
     
     
         18 . The transgenic plant of  claim 17 , selected for increased expression of a nucleic acid encoding a NAP1-like protein. 
     
     
         19 . The transgenic plant of  claim 17 , wherein said isolated nucleic acid encoding a NAP1-like protein encodes a protein as represented in SEQ ID NO:2 
     
     
         20 . The transgenic plant according to  claim 17 , wherein said plant is a crop plant comprising soybean, sunflower, canola, alfalfa, rapeseed or cotton, preferably, the plant is a monocotyledonous plant such as sugarcane, most preferably a cereal, such as rice, maize, wheat, millet, barley, oats, sorghum. 
     
     
         21 . Transgenic plant cells, transgenic plants or transgenic plant parts, including harvestable parts, propagules, seeds or transgenic progeny, and products directly derived thereof, of a plant according to  claim 17 . 
     
     
         22 . A method for increasing yield of a plant comprising introducing into a plant a nucleic acid sequence encoding a NAP1-like protein, or a portion thereof or a sequence hybridising therewith. 
     
     
         23 . The method according to  claim 22 , wherein the nucleic acid sequence encodes homologues, derivatives or active fragments of a NAP1-like protein. 
     
     
         24 . The method according to  claim 22 , wherein said increased yield is increased seed yield. 
     
     
         25 . The method according to  claim 24 , wherein said increased seed yield comprises one or more of total weight of seeds, number of filled seeds and harvest index. 
     
     
         26 . The method according to  claim 22 , wherein the sequence of said nucleic acid is represented as SEQ ID NO: 1, or the nucleic acid encodes a NAP1-like protein as represented in SEQ ID NO: 2. 
     
     
         27 . A composition for increasing yield of a plant, comprising a NAP1-like protein or a nucleic acid encoding a NAP1-like protein. 
     
     
         28 . The composition according to  claim 27 , wherein the NAP1-like protein is represented by SEQ ID NO: 2 or a homologue, derivative or active fragment thereof. 
     
     
         29 . The composition according to  claim 27 , wherein the nucleic acid encoding a NAP1-like protein is represented by SEQ ID NO: 1 or a portion thereof or a sequence hybridising therewith, or encoding a protein as represented in SEQ ID NO:2.