Sulfonylurea-responsive repressor proteins

Abstract

Compositions and methods relating to the use of sulfonylurea-responsive repressors are provided. Compositions include polypeptides that specifically bind to an operator, wherein the specific binding is regulated by a sulfonylurea compound. Compositions also include polynucleotides encoding the polypeptides as well as constructs, vectors, prokaryotic and eukaryotic cells, and eukaryotic organisms including plants and seeds comprising the polynucleotide, and/or produced by the methods. Also provided are methods to provide a sulfonylurea-responsive repressor to a cell or organism, and to regulate expression of a polynucleotide of interest in a cell or organism, including a plant or plant cell.

1 . An isolated polypeptide comprising a sulfonylurea-responsive repressor that specifically binds to a polynucleotide comprising an operator sequence, wherein the binding is regulated by a sulfonylurea compound. 
     
     
         2 . An isolated polypeptide comprising an amino acid substitution to a wild type tetracycline repressor ligand binding domain, wherein the polypeptide or multimer thereof specifically binds to a polynucleotide comprising an operator sequence, wherein the specific binding is regulated by a sulfonylurea compound. 
     
     
         3 . The isolated polypeptide of  claim 2 , wherein the amino acid substitution is selected from the group consisting of an amino acid substitution at amino acid residue position 55, 60, 64, 67, 82, 86, 100, 104, 105, 108, 113, 116, 134, 135, 138, 139, 147, 151, 170, 173, 174 or 177, wherein the amino acid residue position corresponds to the equivalent position using the amino acid numbering of a wild type TetR(B) of SEQ ID NO: 1. 
     
     
         4 - 9 . (canceled) 
     
     
         10 . The isolated polypeptide of  claim 1 , wherein the polypeptide is selected from the group consisting of SEQ ID NO: 3-401, 1206-1213, 1228-1233, and 1240-1243. 
     
     
         11 - 24 . (canceled) 
     
     
         25 . A non-human host cell comprising the isolated polynucleotide of  claim 1  stably incorporated into its genome. 
     
     
         26 . The host cell of  claim 25 , wherein the polynucleotide is operably linked to a promoter functional in the host cell. 
     
     
         27 . The host cell of  claim 25 , wherein the host cell is a prokaryotic cell. 
     
     
         28 . The host cell of  claim 27 , wherein the prokaryotic cell is a bacterium. 
     
     
         29 . The host cell of  claim 28 , wherein the bacterium is an  E. coli  or an  Agrobacterium.    
     
     
         30 . The host cell of  claim 25 , wherein the host cell is a eukaryotic cell. 
     
     
         31 . The host cell of  claim 30 , wherein the eukaryotic cell is a plant cell. 
     
     
         32 . The host cell of  claim 31 , wherein the plant cell is from soybean, rice, corn or tobacco. 
     
     
         33 . The host cell of  claim 32 , wherein the host cell is in a plant. 
     
     
         34 - 55 . (canceled)