Isolation of proteins involved in posttranscriptional gene silencing and methods of use

Abstract

The present disclosure relates, according to some embodiments, to methods of increasing viral resistance in a plant, methods of increasing transgene expression in a plant, and methods of suppressing expression of a native gene in a plant. In some embodiments, the disclosure also relates to polypeptides involved in post-translational gene silencing (PTGS), for e.g., a protein active in PTGS or a suppressor of PTGS. The disclosure further relates to transgenic plant cells in which PTGS is altered (e.g., enhanced or suppressed) according to some embodiments.

1 - 23 . (canceled) 
     
     
         24 . A method of increasing viral resistance in a plant comprising the steps of:
 i) selecting a protein suppressive of PTGS in the plant; and   ii) transforming the plant with a nucleic acid encoding the PTGS suppressive protein.   
     
     
         25 . A method of increasing expression of a transgene in a plant comprising the steps of:
 i) selecting a protein active in PTGS in the plant; and   ii) transforming the plant with a nucleic acid encoding the protein active in PTGS.   
     
     
         26 . A method of suppressing expression of a native gene in a plant comprising:
 i) preparing a vector including a nucleic acid with a sequence of the coding portion of the gene wherein the nucleic acid, upon transcription, products an mRNA molecule double stranded in the region corresponding the to the coding portion of the gene; and   ii) transforming the plant with the vector.   
     
     
         27 . A polypeptide comprising an amino acid sequence having at least 78% identity with the amino acid sequence of SEQ.ID.NO. 2. 
     
     
         28 . A polypeptide according to  claim 27 , wherein the polypeptide comprises the amino acid sequence of SEQ.ID.NO. 2. 
     
     
         29 . A polypeptide comprising the amino acid sequence of SEQ.ID.NO. 4. 
     
     
         30 . A polypeptide comprising an amino acid having at least 97% identity with the amino acid sequence of SEQ.ID.NO. 10. 
     
     
         31 . A polypeptide according to  claim 30 , wherein the polypeptide comprises the amino acid sequence of SEQ.ID.NO. 10. 
     
     
         32 . A transgenic plant cell in which PTGS is enhanced comprising a nucleic acid having a sequence with at least 40% identity with the nucleic acid sequence of SEQ.ID.NO. 3. 
     
     
         33 . A transgenic plant cell in which PTGS is enhanced according to  claim 32 , wherein the nucleic acid comprises the nucleic acid sequence of SEQ.ID.NO. 3. 
     
     
         34 . A transgenic plant cell comprising a nucleic acid having the nucleic acid sequence of SEQ.ID.NO. 3 or SEQ.ID.NO. 9.