Method for increasing stress tolerance in plants

Abstract

The present invention provides methods and compositions for improving the drought resistance of plants. More specifically, the present invention utilizes overexpression of a molybdenum cofactor sulfurase in plants and plant cells.

1 . A method of increasing stress resistance in a plant, comprising overexpressing a molybdenum cofactor sulfurase in the plant, wherein said molybdenum cofactor sulfurase has a homology of at least 90% with SEQ ID NO: 2.  
     
     
         2 . The method of  claim 1 , wherein the plants have increased drought tolerance.  
     
     
         3 . The method of  claim 1 , wherein the plants have increased salt tolerance.  
     
     
         4 . The method of  claim 1 , wherein the plants have increased freezing tolerance.  
     
     
         5 . The method of  claim 1 , wherein the molybdenum cofactor sulfurase has the amino acid sequence of SEQ ID NO: 2.  
     
     
         6 . The method of  claim 1 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid having a sequence which is at least 70% identical to SEQ ID NO: 1.  
     
     
         7 . The method of  claim 1 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which has the sequence of SEQ ID NO: 1.  
     
     
         8 . The method of  claim 1 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which has a sequence which is at least 90% identical to SEQ ID NO: 1.  
     
     
         9 . The method of  claim 1 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which hybridizes under stringent conditions to the complement of SEQ ID NO: 1, wherein said stringent conditions comprise washing in 5×SSC at a temperature of from 50 to 68° C.  
     
     
         10 . (canceled)  
     
     
         11 . The method of  claim 1 , wherein the amino acid sequence of the molybdenum cofactor sulfurase has a homology of at least 95% with SEQ ID NO: 2.  
     
     
         12 . The method of  claim 1 , wherein the plant is  Arabidopsis thalania.    
     
     
         13 . The method of  claim 1 , wherein the plant is selected from the group consisting of wheat, corn, peanut cotton, oat, and soybean.  
     
     
         14 . The method of  claim 1 , wherein the plant is transformed with a vector encoding the molybdenum cofactor sulfurase.  
     
     
         15 . The method of  claim 14 , wherein the plants have increased drought tolerance.  
     
     
         16 . The method of  claim 14 , wherein the plants have increased salt tolerance.  
     
     
         17 . The method of  claim 14 , wherein the plants have increased freezing tolerance.  
     
     
         18 . The method of  claim 14 , wherein the molybdenum cofactor sulfurase has the amino acid sequence of SEQ ID NO: 2.  
     
     
         19 . The method of  claim 14 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid having a sequence which is at least 70% identical to SEQ ID NO: 1.  
     
     
         20 . The method of  claim 14 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which has the sequence SEQ ID NO: 1.  
     
     
         21 . The method of  claim 14 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which has a sequence which is at least 90% identical to SEQ ID NO: 1.  
     
     
         22 . The method of  claim 14 , wherein the molybdenum cofactor sulfurase is encoded by a nucleic acid which hybridizes under stringent conditions to the complement of SEQ ID NO: 1, wherein said stringent conditions comprise washing in 5×SSC at a temperature of from 50 to 68° C.  
     
     
         23 . (canceled)  
     
     
         24 . The method of  claim 14 , wherein the amino acid sequence of the molybdenum cofactor sulfurase has a homology of at least 95% with SEQ ID NO: 2.  
     
     
         25 . The method of  claim 14 , wherein the plant is  Arabidopsis thalania.    
     
     
         26 . The method of  claim 14 , wherein the plant is selected from the group consisting of wheat, corn, peanut cotton, oat, and soybean.  
     
     
         27 .- 80 . (canceled)  
     
     
         81 . An isolated and purified molybdenum cofactor sulfurase having the amino acid sequence of SEQ ID NO: 2.  
     
     
         82 . An isolated and purified enzyme having molybdenum cofactor sulfurase activity, wherein the amino acid sequence of the enzyme has a homology of from 70% to less than 100% to SEQ ID NO: 2  
     
     
         83 . A method of producing the molybdenum cofactor sulfurase of  claim 81 , comprising culturing host cells which have been transformed with a nucleic acid encoding the molybdenum cofactor sulfurase under conditions in which the molybdenum cofactor sulfurase is expressed, and isolating the molybdenum cofactor sulfurase.  
     
     
         84 . A method of producing the enzyme of  claim 82 , comprising culturing host cells which have been transformed with a nucleic acid encoding the enzyme under conditions in which the enzyme is expressed, and isolating the enzyme.  
     
     
         85 . The method of  claim 14 , wherein the vector comprises an inducible promoter.