Replication protein A and use

Abstract

Methods and compositions for modulating DNA metabolism are provided. Nucleotide and amino acid sequences encoding a maize replication protein A subunits are provided. The sequences can be used in expression cassettes for modulating DNA replication, DNA repair, and recombination.

What is claimed is:  
     
         1 . An isolated polynucleotide comprising a member selected from the group consisting of: 
 (a) a nucleic acid sequence having at least 80% sequence identity over the full-length of SEQ ID NOS: 11, 13, 15, 17, 19, or 21, as determined by the GAP algorithm under default parameters, wherein said sequence encodes a polypeptide which enhances homologous recombination as part of an RPA complex; and    (b) a nucleic acid sequence which is fully complementary to the nucleic acid sequence of (a).    
     
     
         2 . The isolated polynucleotide of  claim 1 , wherein the nucleic acid sequence of (a) has at least 85% sequence identity to SEQ ID NOS: 11, 13, 15, 17, 19, or 21.  
     
     
         3 . The isolated polynucleotide of  claim 1 , wherein the nucleic acid sequence has at least 90% sequence identity to SEQ ID NOS: 11, 13, 15, 17, 19, or 21.  
     
     
         4 . The isolated polynucleotide of  claim 1 , wherein the nucleic acid sequence has at least 95% sequence identity to SEQ ID NOS: 11, 13, 15, 17, 19, or 21.  
     
     
         5 . The isolated polynucleotide of  claim 1 , wherein the polynucleotide is SEQ ID NOS: 11, 13, 15, 17, 19, or 21.  
     
     
         6 . An isolated polynucleotide encoding a polypeptide of SEQ ID NOS: 12, 14, 16, 18, 20, or 22, wherein the polypeptide enhances homologous recombination as part of an RPA complex.  
     
     
         7 . An expression cassette comprising the polynucleotide of  claim 1  operably linked to a promoter.  
     
     
         8  A host cell comprising the expression cassette of  claim 7 .  
     
     
         9 . A host cell comprising the polynucleotide of  claim 1 .  
     
     
         10 . The host cell of  claim 9 , wherein the host cell is a plant cell.  
     
     
         11 . The plant cell of  claim 10 , wherein the plant cell is from a monocot.  
     
     
         12 . The plant cell of  claim 11 , wherein the monocot is maize, sorghum, rice, barley, millet, rye, or wheat.  
     
     
         13 . The plant cell of  claim 10 , wherein the plant cell is from a dicot.  
     
     
         14 . The plant cell of  claim 13 , wherein the dicot is soybean, canola, alfalfa, sunflower, or safflower.  
     
     
         15 . A plant comprising the host cell of  claim 10 .  
     
     
         16 . The plant of  claim 15 , wherein the plant is a monocot.  
     
     
         17 . The plant of  claim 16 , wherein the monocot is maize, sorghum, rice, barley, millet, rye, or wheat.  
     
     
         18 . The plant of  claim 15 , wherein the plant is a dicot.  
     
     
         19 . The plant of  claim 18 , wherein the dicot is soybean, canola, alfalfa, sunflower, or safflower.  
     
     
         20 . A seed comprising the host cell of  claim 10 .  
     
     
         21 . The seed of  claim 20 , wherein the seed is from a monocot.  
     
     
         22 . The seed of  claim 21 , wherein the monocot is maize, sorghum, rice, barley, millet, rye, or wheat.  
     
     
         23 . The seed of  claim 20 , wherein the seed is from a dicot.  
     
     
         24 . The seed of  claim 23 , wherein the dicot is soybean, canola, alfalfa, sunflower, or safflower.  
     
     
         25 . An isolated polynucleotide comprising at least 50 contiguous nucleotides of SEQ ID NO: 11, 13, 15, 17, 19, or 21.  
     
     
         26 . An isolated polynucleotide comprising a member selected from the group consisting of: 
 (a) a nucleic acid sequence encoding a polypeptide having at least 90% sequence identity over the entire length of SEQ ID NO: 12, 14, 16, 18, 20, or 22, as determined by the GAP algorithm under default parameters, wherein the encoded polypeptide enhances homologous recombination as part of an RPA complex; and    (b) a nucleic acid sequence which is fully complementary to the nucleic acid sequence of (a).    
     
     
         27 . The isolated polynucleotide of  claim 26 , wherein the nucleic acid sequence of (a) encodes a polypeptide having at least 95% sequence identity to SEQ ID NO: 12, 14, 16, 18, 20, or 22.  
     
     
         28 . The isolated polynucleotide of  claim 26 , wherein the nucleic acid sequence of (a) encodes the polypeptide of SEQ ID NO: 12, 14, 16, 18, 20, or 22.  
     
     
         29 . An isolated polynucleotide comprising a nucleic acid sequence which selectively hybridizes to the full-length complement of SEQ ID NO: 11, 13, 15, 17, 19, or 21 under high stringency hybridization conditions and a wash in 0.1×SCC at 60-65° C., wherein said polynucleotide encodes a polypeptide which enhances homologous recombination as part of an RPA complex.  
     
     
         30 . A method for enhancing homologous recombination in a plant cell, said method comprising transforming the plant cell with an expression cassette comprising the polynucleotide of  claim 1  operably linked to a promoter that drives expression in the plant cell.  
     
     
         31 . The method of  claim 30 , wherein the plant cell is from a monocot.  
     
     
         32 . The method of  claim 31 , wherein the monocot is maize, sorghum, rice, barley, millet, rye, or wheat.  
     
     
         33 . The method of  claim 30 , wherein the plant cell is from a dicot.  
     
     
         34 . The method of  claim 33 , wherein the dicot is soybean, canola, alfalfa, sunflower, or safflower.  
     
     
         35 . A method for increasing pathogen resistance in a plant cell, said method comprising transforming said plant cell with an expression cassette comprising the polynucleotide of  claim 1  operably linked in antisense orientation to a pathogen-inducible promoter.  
     
     
         36 . The method of  claim 35 , wherein the plant cell is from a monocot.  
     
     
         37 . The method of  claim 36 , wherein the monocot is maize, sorghum, rice, barley, millet, rye, or wheat.  
     
     
         38 . The method of  claim 35 , wherein the plant cell is from a dicot.  
     
     
         39 . The method of  claim 38 , wherein the dicot is soybean, canola, alfalfa, sunflower, or safflower.  
     
     
         40 . A method for modulating DNA metabolism in a plant cell, said method comprising transforming said plant cell with an expression cassette comprising the polynucleotide of  claim 1  operably linked to a promoter.  
     
     
         41 . A method for influencing cell cycle in a plant cell, said method comprising transforming said plant cell with an expression cassette comprising the polynucleotide of  claim 1  operably linked to a promoter.