Genes for microsomal delta-12 fatty acid desaturases and related enzymes from plants

Claim 1

Canola oil obtained from the seeds of a Brassica plant having a chimeric gene capable of causing altered levels of fatty acid in a transformed Brassica plant cell, said chimeric gene comprising an isolated nucleic acid fragment comprising a nucleic acid sequence selected from the group consisting of: (a) a nucleic acid sequence encoding a fatty acid desaturase with an amino acid identity of 50% or greater to the polypeptide encoded by any one of the sequences set forth in SEQ ID NOS:1, 3, 5, 7, 9, 11 or 15; (b) a nucleic acid sequence or a part thereof which is useful in antisense inhibition or sense suppression of endogenous desaturase activity in a transformed plant wherein the nucleic acid has an identity of 90% or greater to any one of the sequences set forth in SEQ ID NOS:1, 3, 5, 7, 9, 11, or 15; or (c) a nucleic acid sequence or a part thereof which is useful in antisense inhibition or sense suppression of endogenous desaturase activity in a transformed plant wherein the nucleic acid sequence hybridizes to any one of the sequences set forth in SEQ ID NOS:1, 3, 5, 7, 9, 11 or 15, under one of the following sets of conditions: (i) hybridization in 50 mM Tris, pH 7.6, 6×SSC, 5× Denhardt's, 0.5% sodium dodecyl sulfate (SDS), 100 μg/ml denatured calf thymus DNA at 50° C. and wash twice with 2×SSC, 0.5% SDS at room temperature for 15 min each, then wash twice with 0.2×SSC, 0.5% SDS at room temperature for 15 min each and then wash twice with 0.2×SSC, 0.5% SDS at 50° C. for 15 min each; (ii) hybridization in 6×SSPE, 5× Denhardt's solution, 0.5% sodium dodecyl sulfate (SDS). 5% dextran sulfate, 100 μg/ml denatured salmon sperm DNA at 50° C. and wash twice with 2×SSC, 0.5% SDS at room temperature for 15 min each, then wash twice with 0.2×SSC, 0.5% SDS at room temperature for 15 min each and then wash twice with 0.2×SSC, 0.5% SDS at 50° C. for 15 min each: or (iii) hybridization in 50% formamide, 5×SSPE, 1% sodium dodecyl sulfate (SDS), 1× Denhardt's Reagent, 100 μg/ml denatured salmon sperm DNA at42° C. and wash three times with 2×SSPE, 0.2% SDS at 42° C. for 15 min each, then wash twice with 0.2×SSPE, 0.2% SDS at 55° C. for 30 min each; operably linked to at least one regulatory sequence wherein the oleic acid content of said canola oil is at least 80% and the combined palmitic and stearic acid content is 5% or less.