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

Abstract 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 nudicaulis FAE homolog in yeast cells resulted in accumulation of eicosenoic (20:1 Δ11 ) and 20:1 Δ13 , fatty acids not normally present in wild-type yeast. Northern blot analyses indicated that the Teesdalia nudicaulis FAE 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 .