Transgenic plants expressing L3 delta proteins are resistant to trichothecene fungal toxins

Abstract

Disclosed are specific mutants of L3 and transgenic plants that produce them. The plants exhibit increased resistance to fungal toxins that target ribosomal L3 protein. Also disclosed are transgenic plants that co-produce L3 mutant and an RIP protein, and exhibit increased resistance to various fungal toxins and viruses, while reducing toxicity normally associated with production of the RIP. Uses of the L3 mutants in animals are further disclosed.

1 . A transgenic plant comprising an exogenous nucleic acid comprising a transgene functional therein and that encodes a polypeptide having at least the first 21 to about 99 N-terminal amino acid residues of a full-length eucaryotic L3 protein, or an analog of said polypeptide, wherein said plant exhibits increased resistance to toxins that target eucaryotic ribosomal L3 protein compared to a non-transgenic control plant.  
     
     
         2 . The transgenic plant of  claim 1 , wherein the transgene encodes a polypeptide having from the first 21 to 99 N-terminal amino acid residues of a full-length ribosomal L3 protein.  
     
     
         3 . The transgenic plant of  1 , the transgene encodes a polypeptide having amino acids 1-99 of a eucaryotic ribosomal L3 protein.  
     
     
         4 . The transgenic plant of  claim 1 , wherein the transgene encodes a polypeptide having amino acids 1-100 of a eucaryotic ribosomal L3 protein.  
     
     
         5 . The transgenic plant of  claim 1 , wherein the transgene encodes a polypeptide having amino acids 1-21 of a eucaryotic ribosomal L3 protein.  
     
     
         6 . The transgenic plant of  claim 1 , wherein the transgene is a first transgene, and wherein said exogenous nucleic acid further comprises a second transgene that encodes a ribosome inactivating protein (RIP) that targets a eurcaroytic L3 ribosomal protein.  
     
     
         7 . The transgenic plant of  claim 6  wherein said second transgene encodes Pokeweed Antiviral Protein (PAP)-v.  
     
     
         8 . The transgenic plant of  claim 6 , wherein the second transgene encodes wild-type PAP.  
     
     
         9 . The transgenic plant of  claim 6 , wherein the second transgene encodes PAP-II.  
     
     
         10 . The transgenic plant of  claim 6 , wherein the second transgene encodes ricin or a Shiga toxin.  
     
     
         11 . The transgenic plant of  claim 1 , which is a monocot plant.  
     
     
         12 . The transgenic plant of  claim 1 , which is a cereal crop plant.  
     
     
         13 . The transgenic plant of  claim 12 , wherein the cereal crop plant is maize, rice, wheat, oat, barley or wheat.  
     
     
         14 . The transgenic plant of  claim 1 , which is a dicot plant.  
     
     
         15 . Seed derived from-the transgenic plant of  claim 1 .  
     
     
         16 . Seed derived from the transgenic plant of  claim 6 .  
     
     
         17 . A method of making a transgenic plant having increased resistance to infestation by fungi that produce toxins that target a eurcaryotic L3 protein, comprising preparing a transgenic plant having a genome that contains an exogenous nucleic acid comprising a transgene encoding a polypeptide having at least the first 21 to about 99 N-terminal amino acid residues of a full-length eucaryotic L3 protein or an analog thereof, wherein expression of the transgene in the transgenic plant confers increased resistance to toxins that target a eucaryotic ribosomal L3 protein compared to a non-transgenic control plant.  
     
     
         18 . The method of  claim 17 , wherein said preparing a transgenic plant comprises transforming a protoplast from a cell of a plant with the exogenous nucleic acid to produce a transformed protoplast, and generating the transgenic plant from the transformed protoplast.  
     
     
         19 . The method of  claim 17 , wherein said preparing a transgenic plant comprises introducing the exogenous nucleic acid into tissue of a plant to produce transformed plant tissue, and regenerating the transgenic plant from the transformed plant tissue.  
     
     
         20 . A method of making a transgenic plant having resistance to infestation by fungi that produce toxins that target a eurcaryotic L3 protein, comprising preparing a transgenic plant having a genome that contains a first exogenous nucleic acid having a first transgene encoding a polypeptide having at least the first 21 to about 99 N-terminal amino acid residues of a full-length eucaryotic L3 protein or an analog thereof, and a second exogenous nucleic acid having a second transgene encoding an RIP protein that targets a eucaryotic ribosomal L3 protein, wherein expression of the first and second transgenes in the transgenic plant confers increased resistance to the fungi, and with less toxicity to the plant compared to a transgenic control plant that contains the second transgene but does not contain the first transgene.