Method for the production of polyunsaturated fatty acids, new biosynthetic genes and new plant expression constructs.

Method for producing fatty acid esters with a high content of polyunsaturated fatty acids with at least two characterized double bonds because a non-human organism, producing fatty acid esters, at least one nucleic acid selected from group a) is introduced a 1, SEQ ID NO: 3, SEQ ID NO: 5 or SEQ ID NO: 11, b) nucleic acids are obtained due to the degenerate code by retranslation of the amino acid sequences depicted nucleic with the sequence shown in SEQ ID NO acid in SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 6 or SEQ ID NO: 12, c) derivatives of the nucleic acids represented in SEQ ID NO: 1, SEQ ID NO: 3, SEQ ID NO: 5 or SEQ ID NO: 11 encoding biologically active portions of a desaturase and have at least 50% identity to the amino acid sequence of SEQ ID NO: 2, 4, 6 or 12, is grown the body and isolate the fatty acid esters obtained from the body.