Isolation and Use of FAD2 and FAE1 From Camelina

Abstract

The present invention provides isolated FAD2 and FAE1 genes and FAD2 and FAE1 protein sequences of Camelina species, e.g., Camelina sativa , mutations in Camelina FAD2 and FAE1 genes, and methods of using the same. In addition, methods of altering Camelina seed composition and/or improving Camelina seed oil quality are disclosed. Furthermore, methods of breeding Camelina cultivars and/or other closely related species to produce plants having altered or improved seed oil and/or meal quality are provided.

We claim: 
     
         1 . An isolated polynucleotide encoding a plant fatty acid synthesis polypeptide, wherein the isolated polynucleotide encodes a plant fatty acid desaturase (FAD) polypeptide, comprising a sequence sharing at least 93% identity to SEQ ID NO: 1, 2, 3, 45, 46, 48, 51, 54, 55, 56, 60, or 61; or the isolated polynucleotide encodes a plant fatty acid elongase (FAE) polypeptide comprising a sequence sharing at least 91% identity to SEQ ID NO: 4, 5, 6, 47, 49, 50, 52, 53, 57, 58, 59, 62, or 63. 
     
     
         2 . The isolated FAD polynucleotide of  claim 1 , wherein the polynucleotide comprises a sequence selected from the group consisting of SEQ ID NOs 1, 2, 3, 45, 46, 48, 51, 54, 55, 56, 60, and 61; or the isolated FAE polynucleotide of  claim 1 , wherein the polynucleotide comprises a sequence selected from the group consisting of SEQ ID NOs 4, 5, 6, 47, 49, 50, 52, 53, 57, 58, 59, 62, and 63. 
     
     
         3 . The isolated polynucleotide of  claim 1 , wherein the FAD polynucleotide comprises one or more mutations listed in Tables 7 to 9; or wherein the FAE polynucleotide comprises one or more mutations listed in Tables 10 to 12. 
     
     
         4 . An isolated FAD polypeptide comprising an amino acid sequence sharing at least 93% identity to a FAD polypeptide encoded by the FAD polynucleotide of  claim 1 ; or an isolated FAE polypeptide comprising an amino acid sequence sharing at least 88% identity to a FAE polypeptide encoded by the FAE polynucleotide of  claim 1 . 
     
     
         5 . A plant cell, plant part, plant tissue culture or whole plant comprising at least one FAD2 gene comprising at least one mutation that disrupts and/or alters the function of the at least one FAD2 gene and/or at least one FAE1 gene comprising at least one mutation that disrupts and/or alters the function of the at least one FAE1 gene. 
     
     
         6 . The plant cell, plant part, plant tissue culture or whole plant of  claim 5  wherein the FAD2 gene is FAD2 A, FAD2 B and/or FAD2 C; and wherein the FAE1 gene is FAE1 A. FAE1 Band/or FAE1 C. 
     
     
         7 . The plant cell, plant part, plant tissue culture or whole plant of  claim 5 , wherein the plant is a  Camelina  plant. 
     
     
         8 . The  Camelina  plant cell, plant part, plant tissue culture or whole plant of  claim 5  further comprising one or more additional genetic changes selected from the group consisting of:
 (a) one or more non-FAD2, non-FAE1 fatty acid synthesis genes with at least one mutation that disrupts and/or alters the function of that gene; 
 (b) a chimeric gene comprising a double stranded RNA region that is both homologous and complementary to a region of one or more non-FAD2, non-FAE1 fatty acid synthesis genes; and 
 (c) a chimeric gene comprising one or more non-FAD2, non-FAE1 fatty acid synthesis genes, wherein the non-FAD2, non-FAE1 fatty acid synthesis genes are operably linked to an overexpression promoter. 
 
     
     
         9 . The plant cell, plant part, tissue culture or whole plant of  claim 8 , wherein the additional fatty acid gene is selected from the group consisting of FAD3, a hydroxylase and a thioesterase. 
     
     
         10 . The plant cell, plant part, plant tissue culture or whole plant of  claim 5 ; wherein the mutation is selected from any one of mutations listed in Tables 7 to 12 for a particular FAD2 or FAE1 gene. 
     
     
         11 . A method of increasing the activity of a FAD2 and/or FAE1 protein in a  Camelina  plant cell, plant part, tissue culture or whole plant comprising transforming the plant cell, plant part, tissue culture or whole plant with a chimeric gene comprising one FAD2 and/or FAE1 gene encoding the polypeptide of  claim 4 , or functional variants thereof.