Methods for increasing plant cell proliferation by functionally inhibiting a plant cyclin inhibitor gene

Abstract

The present invention provides methods for modulating the growth and/or yield of plants. In particular the methods comprise the use of agents which functionally inhibit the expression of plant D-like cyclin inhibitors including isolated polynucleotide sequences which interact with DNA or RNA encoding proteins capable of binding plant D-like cyclins. Further, the present invention provides recombinant polynucleotide sequences, vectors and host cells which encode proteins capable of binding to and inactivating the activity of plant D-like cyclin/cyclin dependent kinase complexes preventing plant cells from exiting the cell cycle. Methods for determining and agents which are inhibitors of the BRO cyclin dependent kinase inhibitor proteins which are capable of modulating plant cell cycle progression are also provided. Methods for the production of transgenic plant cells and plants with increased growth rates and yields when compared to wild-type plants are also provided.

1 .- 31 . (canceled) 
     
     
         32 . A method for producing a hyperplastic variant plant, comprising functionally inactivating expression of one or more plant D-like cyclin inhibitor gene in a plant, wherein a hyperplastic variant is produced, with the hyperplasticity being relative to a wild-type plant. 
     
     
         33 . The method of  claim 32 , wherein the plant D-like cyclin inhibitor gene encodes a protein having at least 70% identity to SEQ ID NO: 8. 
     
     
         34 . The method of  claim 32 , wherein the genome of said hyperplastic variant plant comprises a structurally disrupted plant D-like cyclin inhibitor gene. 
     
     
         35 . The method of  claim 32 , wherein the expression of the plant D-like cyclin inhibitor gene in the plant is functionally inactivated by introducing an antisense polynucleotide, a double stranded polynucleotide, or an inverted repeat polynucleotide into the plant, wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is homologous to the plant D-like cyclin inhibitor gene. 
     
     
         36 . The method of  claim 32 , wherein the functionally inactivated plant D-like cyclin inhibitor gene is structurally disrupted by homologous recombination with a targeting construct. 
     
     
         37 . The method of  claim 35 , wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is homologous to the promoter, the enhancers, the coding region, the flanking sequence, or the introns of the plant D-like cyclin inhibitor gene. 
     
     
         38 . The method of  claim 37 , wherein the plant D-like cyclin inhibitor gene in the plant is functionally inactivated by one or more inverted repeat polynucleotide homologous to the promoter region of the plant D-like cyclin inhibitor gene. 
     
     
         39 . The method of  claim 35 , wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is operably linked to a plant promoter. 
     
     
         40 . The method of  claim 36 , wherein the plant promoter is CaMV 35S, tomato E8, patatin, ubiquitin, mannopine synthase (mas), rice actin 1, soybean seed protein glycinin (Gyl), or soybean vegetative storage protein (vsp) promoter. 
     
     
         41 . A polynucleotide construct comprising a recombinant sequence that is homologous to one or more plant D-like cyclin inhibitor gene, wherein the recombinant sequence can functionally inactivate the plant D-like cyclin inhibitor when introduced into a plant. 
     
     
         42 . The polynucleotide construct of  claim 41 , wherein the plant D-like cyclin inhibitor gene encodes a protein having at least 70% identity to SEQ ID NO: 8. 
     
     
         43 . The polynucleotide construct of  claim 41 , wherein the recombinant sequence is an antisense polynucleotide, a double stranded polynucleotide, or an inverted repeat polynucleotide. 
     
     
         44 . The polynucleotide construct of  claim 43 , wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is homologous to the promoter, the enhancers, the coding region, the flanking sequence, or the introns of the plant D-like cyclin inhibitor gene. 
     
     
         45 . The polynucleotide construct of  claim 43 , wherein the inverted repeat polynucleotide is homologous to the promoter region of the plant D-like cyclin inhibitor gene. 
     
     
         46 . The method of  claim 43 , wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is operably linked to a plant promoter. 
     
     
         47 . The method of  claim 46 , wherein the plant promoter is CaMV 35S, tomato E8, patatin, ubiquitin, mannopine synthase (mas), rice actin 1, soybean seed protein glycinin (Gyl), or soybean vegetative storage protein (vsp) promoter. 
     
     
         48 . A hyperplastic plant having a functionally inactivated plant D-like cyclin inhibitor gene, the hyperplasticity being relative to a wild-type plant. 
     
     
         49 . The hyperplastic plant of  claim 48 , wherein the plant D-like cyclin inhibitor gene is functionally inactivated by an antisense polynucleotide, a double stranded polynucleotide, or an inverted repeat polynucleotide, wherein the antisense polynucleotide, a double stranded polynucleotide, or an inverted repeat polynucleotide is homologous to the promoter, the enhancers, the coding region, the flanking sequence, or the introns of the plant D-like cyclin inhibitor gene. 
     
     
         50 . The hyperplastic plant of  claim 49 , wherein the antisense polynucleotide, the double stranded polynucleotide, or the inverted repeat polynucleotide is homologous to the promoter region of the plant D-like cyclin inhibitor gene. 
     
     
         51 . The hypertrophic plant of  claim 49 , wherein the antisense polynucleotide, the double stranded polynucleotide, or an inverted repeat polynucleotide is operably linked to a plant promoter. 
     
     
         52 . The hypertrophic plant of  claim 51 , wherein the plant promoter is CaMV 35S, tomato E8, patatin, ubiquitin, mannopine synthase (mas), rice actin 1, soybean seed protein glycinin (Gyl), or soybean vegetative storage protein (vsp) promoter. 
     
     
         53 . A method for increasing the growth rate, seed yield, root biomass, shoot biomass, and/or ear height of a plant, comprising functionally inactivating expression of one or more plant D-like cyclin inhibitor gene in a plant wherein the growth rate, seed yield, root biomass, shoot biomass, and/or ear height of the plant is increased relative to a wild-type plant of the same species having the functional plant D-like cyclin inhibitor gene.