A Teesdalia nudicaulis FAE1 complements the fae1 mutation in transgenic Arabidopsis thaliana plants and shows a preference for elongating oleic acid to eicosenoic acid

Using a PCR-based approach, a genomic clone of a putative fatty acid elongase (FAE) showing high similarity to plant microsomal fatty acid elongases, was isolated from Teesdalia nudicaulis. The genomic clone contains an open reading frame of 1521 bp encoding a protein of 507 amino acids. Expression of the Teesdalia nudicaulisFAE homolog in yeast cells resulted in accumulation of eicosenoic (20:1Δ11) and 20:1Δ13, fatty acids not normally present in wild-type yeast. Northern blot analyses indicated that the Teesdalia nudicaulisFAE is expressed in seeds but not in vegetative tissues. Transformation of a low eicosenoic acid Arabidopsis thaliana mutant line (AC56) with the Teesdalia nudicaulis FAE restored elongase activity and the high proportion of eicosenoic acid typically found in wild-type Arabidopsis seed oils. The recombinant FAE expressed in a yeast transformant showed a strong preference for elongating an oleoyl to an eicosenoyl moiety in vitro.