Nucleotide sequences mediating male fertility and method of using same

Abstract

Nucleotide sequences mediating male fertility in plants are described, with DNA molecule and amino acid sequences set forth. Promoter sequences and their essential regions are also identified. The nucleotide sequences and promoter sequences are useful in methods mediating male fertility in plants, as described. Vectors, plant cells, and plants comprising the nucleotide sequences and/or promoter regions are also provided.

That which is claimed: 
     
         1 . A method of controlling male fertility of a plant, said method comprising the steps of:
 (a) Selecting a male-sterile plant which comprises within its genome a first polynucleotide having a coding region at least 95% identical to SEQ ID NO: 1, wherein said plant does not produce a polypeptide at least 95% identical to the full length of SEQ ID NO: 2;   (b) introducing into said plant an expression construct comprising an inducible promoter operably linked to a second polynucleotide, wherein said second polynucleotide encodes the polypeptide of SEQ ID NO: 2; and   (c) optionally inducing said promoter in said plant to result in male fertility.   
     
     
         2 . A method of reproducing a plant produced according to the method of  claim 1 , further comprising:
 (a) sowing and cultivating seed of the plant to provide growing male sterile plants;   (b) inducing conversion of the growing plants to male fertile form under conditions which induce the promoter to express the operably-linked polynucleotide;   (c) open-pollinating the growing plants in isolation to produce seed; and   (d) harvesting the seed.   
     
     
         3 . A controllably male sterile plant produced according to the method of  claim 1 . 
     
     
         4 . The method of  claim 1 , wherein said first and polynucleotide comprises a sequence having at least 95% identity to the full length of SEQ ID NO: 7. 
     
     
         5 . The method of  claim 1 , wherein said plant is maize. 
     
     
         6 . The method of  claim 1 , wherein said second polynucleotide comprises a sequence having at least 95% identity to the full length of SEQ ID NO: 1. 
     
     
         7 . An isolated polynucleotide operably linked to a heterologous regulatory region, wherein said polynucleotide is selected from the group consisting of:
 (a) a polynucleotide having at least 86% identity to the full length of SEQ ID NO: 1;   (b) a polynucleotide having at least 90% identity to the full length of SEQ ID NO: 1; and   (c) a polynucleotide having at least 95% identity to a the full length of SEQ ID NO: 1.   
     
     
         8 . A plant cell comprising the polynucleotide and operably linked heterologous regulatory region of  claim 7 . 
     
     
         9 . A method of controlling male fertility of a plant, wherein the method comprises identifying a plant comprising a first polynucleotide selected from the group consisting of:
 (a) a polynucleotide having at least 86% identity to the full length of SEQ ID NO: 1;   (b) a polynucleotide having at least 90% identity to the full length of SEQ ID NO: 1; and   (c) a polynucleotide having at least 95% identity to the full length of SEQ ID NO: 1, and controlling expression of said first polynucleotide in the plant, wherein said male fertility is controlled.   
     
     
         10 . The method of  claim 9 , wherein the expression of the first polynucleotide is repressed. 
     
     
         11 . The method of  claim 9 , wherein expression of the first polynucleotide is repressed by delivering into the plant a second polynucleotide which represses expression of the first polynucleotide. 
     
     
         12 . The method of  claim 9 , wherein expression of the first polynucleotide is repressed by delivering into the plant a second polynucleotide oriented in the antisense direction relative to the first polynucleotide, wherein the second polynucleotide is selected from the group consisting of:
 (a) a polynucleotide having at least 86% identity to the full length of SEQ ID NO: 1;   (b) a polynucleotide having at least 90% identity to the full length of SEQ ID NO: 1; and   (c) a polynucleotide having at least 95% identity to the full length of SEQ ID NO: 1.   
     
     
         13 . The method of  claim 9 , wherein said first polynucleotide has at least 90% identity to the full length of SEQ ID NO: 1. 
     
     
         14 . The method of  claim 9 , wherein said first polynucleotide has at least 95% identity to the full length of SEQ ID NO: 1. 
     
     
         15 . The polynucleotide of  claim 7 , wherein said polynucleotide encodes a polypeptide having at least 87% identity to SEQ ID NO: 2. 
     
     
         16 . The method of  claim 9 , wherein said first polynucleotide encodes a polypeptide having at least 87% identity to SEQ ID NO: 2. 
     
     
         17 . The polynucleotide of  claim 7 , wherein said polynucleotide encodes a protein critical to male fertility in plants. 
     
     
         18 . An expression cassette comprising a polynucleotide and a heterologous regulatory region, wherein said polynucleotide encodes a polypeptide having at least 95% identity to the full length of SEQ ID NO: 22. 
     
     
         19 . A plant comprising the recombinant expression cassette of  claim 18 , wherein said plant is male-fertile. 
     
     
         20 . A plant comprising the expression cassette of  claim 18 , wherein said plant is male-sterile. 
     
     
         21 . The plant of  claim 19 , wherein said plant is sorghum, maize, or rice. 
     
     
         22 . The plant of  claim 20 , wherein said plant is sorghum, maize, or rice. 
     
     
         23 . An isolated or recombinant polynucleotide which has at least 95% identity to the full length of SEQ ID NO: 19 and is capable of driving male-tissue-preferred expression of an operably-linked polynucleotide.