Use of dimerization domain component stacks to modulate plant architecture

Abstract

This invention provides means for altering the harvest index of crop plants by modulating the expression of transgenic genes using dimerization domain and component stacks, thereby modulating plant architecture. The transgene/dimerization domain stacks are provided in a single transformation vector unit and are used to modulate plant growth, yield, and harvest index in plants.

What is claimed is: 
     
         1 . An isolated nucleic acid encoding a dimerization domain, the dimerization domain comprising a consensus amino acid sequence of SEQ ID NO: 41 or a sequence that is 90% identical to SEQ ID NO: 41. 
     
     
         2 . The nucleic acid of  claim 1  encoding a dimerization domain, the dimerization domain consisting essentially of the amino acid sequence of SEQ ID NO: 19 or 21 or a sequence that is 90% identical to SEQ ID NO: 19 or 21. 
     
     
         3 . The isolated nucleic acid of  claim 1  comprising a polynucleotide sequence of SEQ ID NO: 9. 
     
     
         4 . The isolated nucleic acid of  claim 1 , wherein the dimerization domain binds to a native maize D8 protein or D9 protein to produce a nonfunctional D8 or D9 dimer. 
     
     
         5 . A recombinant expression cassette, comprising the polynucleotide of  claim 3 , wherein the polynucleotide is operably linked to a promoter. 
     
     
         6 . A host cell comprising the expression cassette of  claim 5 . 
     
     
         7 . A transgenic plant comprising the recombinant expression cassette of  claim 5 . 
     
     
         8 . The transgenic plant of  claim 7 , wherein said plant is a monocot. 
     
     
         9 . The transgenic plant of  claim 7 , wherein said plant is a dicot. 
     
     
         10 . The transgenic plant of  claim 7 , wherein said plant is selected from the group consisting of: maize, soybean, sunflower, sorghum, canola, wheat, alfalfa, cotton, rice, barley, millet, peanut, sugar cane, grass, turfgrass and cocoa. 
     
     
         11 . A transgenic seed from the transgenic plant of  claim 7 . 
     
     
         12 . A method of modulating harvest index in a transgenic plant, the method comprising expressing a recombinant polynucleotide encoding a dimerization domain of a dwarf gene. 
     
     
         13 . The method of  claim 12 , wherein the dwarf gene is D8 from maize. 
     
     
         14 . The method of  claim 12 , wherein the polynucleotide comprises the nucleic acid sequence of  claim 3  operably linked to a promoter. 
     
     
         15 . The method of  claim 12 , wherein the plant is selected from the group consisting of: maize, soybean, sunflower, sorghum, canola, wheat, alfalfa, cotton, rice, barley, millet, peanut, sugar cane, grass, turfgrass and cocoa. 
     
     
         16 . The method of  claim 12 , wherein the dimerization domain forms a non-functional dimer of endogenous maize D8 or D9 protein. 
     
     
         17 . A method of modulating plant tissue growth with a dimerization domain in a plant, comprising expressing a recombinant expression cassette comprising the polynucleotide of  claim 3  operably linked to a promoter. 
     
     
         18 . The method of  claim 17 , wherein plant tissue growth is due to reduced inhibition by endogenous gibberellic acid. 
     
     
         19 . The method of  claim 17 , wherein the plant is selected from the group consisting of: maize, soybean, sorghum, canola, wheat, alfalfa, cotton, rice, barley, millet, peanut, sugar cane, grass, turfgrass and cocoa. 
     
     
         20 . A product derived from the method of processing of transgenic plant component expressing an isolated polynucleotide encoding a dimerization domain, the method comprising:
 a. growing a plant that expresses a polynucleotide having at least 90% sequence identity to the full length sequence of SEQ ID NO: 9, operably linked to a promoter; and   b. processing the plant component to obtain a product.   
     
     
         21 . The product of  claim 20 , wherein the plant component is a seed. 
     
     
         22 . A product according to  claim 20 , wherein the polynucleotide further encodes a polypeptide selected of SEQ ID NO: 19. 
     
     
         23 . A product according to  claim 20 , which is a constituent of ethanol. 
     
     
         24 . The method of  claim 12 , wherein the plant has improved canopy shape. 
     
     
         25 . The method of  claim 12 , wherein the plant has increased photosynthetic capacity in leaf tissue. 
     
     
         26 . The method of  claim 12 , wherein the plant has improved stalk strength. 
     
     
         27 . The method of  claim 12 , wherein the plant has improved plant standibility. 
     
     
         28 . The method of  claim 12 , wherein the plant has altered vascular bundle structure or number. 
     
     
         29 . The method of  claim 12 , wherein the plant has increased root biomass. 
     
     
         30 . The method of  claim 12 , wherein the plant has enhanced root growth. 
     
     
         31 . The method of  claim 12 , wherein the plant has modulated shoot development. 
     
     
         32 . The method of  claim 12 , wherein the plant has modulated leaf development. 
     
     
         33 . The method of  claim 12 , wherein the plant has improved silage quality and digestibility. 
     
     
         34 . The method of  claim 14 , wherein the promoter is selected from the group consisting of a leaf specific promoter, vascular element preferred promoter and a root specific promoter.