Dominant Gene Suppression Transgenes and Methods of Using Same

Abstract

Pairs of plants are provided in which complementing constructs result in suppression of a parental phenotype in the progeny. Methods to generate and maintain such plants, and methods of use of said plants, are provided, including use of parental plants to produce sterile plants for hybrid seed production. Also provided are methods for testing allelic variants.

What is claimed is: 
     
         1 . A breeding pair of plants comprising four polynucleotides, wherein
 (a) the first plant of said pair comprises (i) a first polynucleotide which encodes a gene product and is operably linked to a promoter A, and (ii) a second polynucleotide which encodes a pIR polynucleotide targeting a promoter sequence B, wherein promoter B is not present in said first plant; and   (b) The second plant of said pair comprises (iii) a third polynucleotide which encodes a gene product and is operably linked to said promoter B, and (ii) a fourth polynucleotide which encodes a pIR polynucleotide targeting said promoter A, wherein promoter A is not present in said second plant.   
     
     
         2 . The breeding pair of plants of  claim 1 , wherein one or more of said four polynucleotides is exogenous. 
     
     
         3 . The breeding pair of plants of  claim 1 , wherein said gene products affect the same phenotypic trait. 
     
     
         4 . The breeding pair of plants of  claim 3 , wherein said trait is male fertility. 
     
     
         5 . The breeding pair of plants of  claim 3 , wherein said trait is female fertility. 
     
     
         6 . The breeding pair of plants of  claim 1 , wherein
 (a) said first polynucleotide is selected from the group consisting of polynucleotides encoding maize MS45, maize BS7, maize 5126, and the corresponding orthologs from  Arabidopsis  and rice;   (b) said second promoter is selected from the group consisting of rice MS45, rice BS7, rice 5126,  Arabidopsis  BS7,  Arabidopsis  5126, and  Arabidopsis  MS45 promoters;   (c) said third polynucleotide is selected from the group consisting of polynucleotides encoding maize MS45, maize BS7, maize 5126, and the corresponding orthologs from  Arabidopsis  and rice;   (d) said first promoter is selected from the group consisting of rice MS45, rice BS7, rice 5126,  Arabidopsis  BS7,  Arabidopsis  5126, and  Arabidopsis  MS45 promoters.   
     
     
         7 . A method of generating plants lacking a particular phenotype from parents exhibiting said phenotype, comprising crossing the breeding pair of plants of  claim 3 . 
     
     
         8 . A cell of a plant of  claim 1 . 
     
     
         9 . Seed or progeny of a plant of  claim 1 . 
     
     
         10 . A method of evaluating the function of an exogenous allelic variant of an endogenous gene in a plant, wherein the endogenous gene is operably linked to its endogenous promoter in the plant, comprising:
 (a) silencing said endogenous gene using a promoter inverted repeat construct targeting said endogenous promoter;   (b) expressing said exogenous allelic variant operably linked to a non-target promoter; and   (c) evaluating the phenotype of the plant or its progeny.   
     
     
         11 . The method of  claim 10 , comprising the further steps of
 (a) crossing the plant or progeny of  claim 10  with a second plant, wherein said second plant comprises a promoter inverted repeat targeting the promoter operably linked to said exogenous allelic variant in the plant of  claim 10 ; and   (b) evaluating the phenotype of the progeny of said cross.   
     
     
         12 . The method of  claim 10 , wherein the exogenous allelic variant is derived from a second species.