Method for Producing Polyunsaturated C20 and C22 Fatty Acids with at Least Four Double Bonds in Transgenic Plants

An isolated nucleic acid comprising a nucleotide sequence selected from the group consisting of:

• a) the nucleotide sequence shown in SEQ ID NO:
• 1, 3, 5, 7, 9, 23 or 25,
• b) a nucleotide sequence which codes for a protein with the polypeptide sequence shown in SEQ ID NO:
• 2, 4, 6, 8, 10, 24, or 26,
• c) a derivative of the nucleotide sequence shown in SEQ ID NO:
• 1 which codes for a polypeptide having at least 70% identity at the amino acid level with SEQ ID NO:
• 2 and a Δ6-desaturase activity,
• d) a derivative of the nucleotide sequence shown in SEQ ID NO:
• 3, SEQ ID NO:
• 5 or SEQ ID NO:
• 7 which codes for a polypeptide having at least 70% identity at the amino acid level with SEQ ID NO:
• 4, SEQ ID NO:
• 6 or SEQ ID NO:
• 8 and which has a Δ6-elongase activity,
• e) a derivative of the nucleotide sequence shown in SEQ ID NO:
• 9 which codes for a polypeptide having at least 40% identity at the amino acid level with SEQ ID NO:
• 10 and which has a Δ5-desaturase activity,
• f) a derivative of the nucleotide sequence shown in SEQ ID NO:
• 23 which codes for a polypeptide with at least 40% identity at the amino acid level with SEQ ID NO:
• 24 and which has a ω3-desaturase activity, and
• g) a derivative of the nucleotide sequence shown in SEQ ID NO:
• 25 which codes for a polypeptide with at least 40% identity at the amino acid level with SEQ ID NO:
• 26 and which has a Δ12-desaturase activity.