Methods and compositions for synthesis of long chain poly-unsaturated fatty acids in plants

A nucleic acid construct comprising the nucleotide sequence depicted in SEQ ID NO:5, wherein said nucleotide sequence is operably associated with a transcription or an expression control sequence functional in a plant cell, wherein said nucleotide sequence encodes a functionally active polypeptide which desaturates a fatty acid molecule at carbon 5 from the carboxyl end of said fatty acid molecule.

A nucleic acid construct comprising a nucleotide sequence which encodes a functionally active desaturase having the amino acid sequence depicted in SEQ ID NO:6, wherein said nucleotide sequence is operably associated with a promoter functional in a plant cell.

A microbial or plant host cell comprising at least one copy of a DNA sequence which encodes a functionally active Mortierella alpina fatty acid desaturase having the amino acid sequence as depicted in a SEQ NO:6, wherein said cell or parent of said cell was transformed with a vector comprising said DNA sequence, and wherein said DNA sequence is operably associated with an expression control sequence.

A method for obtaining altered long chain polyunsaturated fatty acid biosynthesis in a plant, said method comprising:

• growing a plant having cells which contain one or more transgenes encoding a transgene expression product which desaturates a fatty acid molecule at carbon 5 from the carboxyl end of said fatty acid molecule, wherein said expression product comprises the amino acid sequence depicted in SEQ ID NO:6 wherein said one or more transgenes is operably associated with an expression control sequence, under conditions whereby said one or more transgenes is expressed, whereby long chain polyunsaturated fatty acid biosynthesis in said cells is altered.

A nucleic acid construct comprising:

• two or more nucleotide sequences depicted in a SEQ ID NO:
• selected from the group consisting of SEQ ID NO:1, SEQ ID NO:3, and SEQ ID NO:5 linked to a heterologous nucleotide sequence.

A nucleic acid construct comprising:

• one or more nucleotide sequences depicted in a SEQ ID NO:
• selected from the group consisting of SEQ ID NO:1, SEQ ID NO:3, and SEQ ID NO:5 operably associated with an expression control sequence functional in a plant cell.