DNA sequences encoding antifungal proteins

Abstract

The present invention provides DNA sequences encoding antifungal peptides which comprise at least six amino acid residues identical to a run of amino acid residues found between position 21 and position 51 of the Rs-AFP2 antifungal protein sequence (SEQ ID NO: 35) or a substantially homologous protein. The peptides are useful for combating fungal diseases in agricultureal, pharmaceutical or perservative applications

What is claimed is:  
     
         1 . An isolated DNA sequence encoding an antifungal peptide, wherein said DNA sequence is selected from the group consisting of: 
 (a) a DNA sequence wherein said antifungal peptide consists of at least six amino acid residues identical to a run of amino acid residues found between position 21 and 51 of SEQ ID NO: 35; and    (b) a DNA sequence that comprises (a) and further comprises a DNA sequence that encodes Rs-AFP1 (SEQ ID NO: 34) or Rs-AFP2 (SEQ ID NO: 35).    
     
     
         2 . The isolated DNA sequence of  claim 1 , wherein said antifungal peptide consists of at least six amino acid residues identical to a run of amino acid residues found between position 21 and 51 of SEQ ID NO: 35.  
     
     
         3 . The isolated DNA sequence of  claim 1 , wherein said DNA sequence encodes a peptide which consists of at least six amino acid residues identical to a run of amino acid residues found between position 21 and 51 of SEQ ID NO: 35 and encodes Rs-AFP1 (SEQ ID NO: 34) or Rs-AFP2 (SEQ ID NO: 35).  
     
     
         4 . A recombinant vector comprising the DNA sequence of  claim 1 .  
     
     
         5 . A non-human biological system comprising the recombinant vector of  claim 4 .  
     
     
         6 . The biological system of  claim 5 , which is a plant cell.  
     
     
         7 . A transgenic plant comprising the transgenic plant cell of  claim 6 .  
     
     
         8 . The transgenic plant of  claim 7 , wherein said plant has improved resistance to a fungal pathogen.  
     
     
         9 . Transgenic seed from the transgenic plant of  claim 8 .  
     
     
         10 . A method of producing an antifungal peptide comprising: 
 (a) obtaining the biological system of  claim 5;     (b) growing the biological system under conditions which allow the expression of the antifungal peptide; and    (c) isolating the antifungal peptide.    
     
     
         11 . A method for making a transgenic plant capable of producing an antifungal peptide, comprising: 
 (a) stably integrating the DNA sequence of  claim 1  into the genome of plant cells; and    (b) regenerating stably transformed plants from said transformed plant cells, wherein said stably transformed plants produce at least one antifungal peptide.    
     
     
         12 . A transgenic plant made by the method of  claim 11 .  
     
     
         13 . Transgenic seed from the transgenic plant of  claim 12 .  
     
     
         14 . A method of producing hybrid plant seed comprising crossing the transgenic plant of  claim 7  with a plant having a different genotype.  
     
     
         15 . Hybrid seed produced by the method of  claim 14 .  
     
     
         16 . A hybrid plant produced by growing the hybrid seed of  claim 15 .  
     
     
         17 . A method of producing a hybrid plant with improved fungal resistance comprising: 
 (a) crossing a first transgenic parent plant comprising a DNA sequence that encodes an antifungal peptide consisting of at least six amino acid residues identical to a run of amino acid residues found between position 21 and 51 of SEQ ID NO: 35 with a second transgenic parent plant comprising a DNA sequence that encodes SEQ ID NO: 34 or SEQ ID NO: 35;    (b) harvesting the resultant first generation hybrid seed;    (c) planting said hybrid seed under conditions which allow said seed to germinate and grow into hybrid plants; and    (d) testing said hybrid plants for improved fungal resistance.    
     
     
         18 . A hybrid plant produced by the method of  claim 17.