Portal de Periódicos da CAPES

Acyl-CoA Z9- and Z10-desaturase genes from a New Zealand leafroller moth species, Planotortrix octo

2002; Elsevier BV; Volume: 32; Issue: 9 Linguagem: Inglês

10.1016/s0965-1748(01)00176-x

1879-0240

Ge‐Fei Hao, W Liu, Marion O’Connor, Wendell L. Roelofs,

Neurobiology and Insect Physiology Research

Two cDNAs encoding acyl-CoA Z9-desaturase from the fat body and Z10-desaturase from the pheromone gland of the greenhead leafroller moth, Planotortrix octo, were obtained by RACE PCR. The Z9-desaturase (Pocto-Z9) cDNA spans 2291 nt with an ORF encoding a 352 amino-acid protein, which has 65% identity to Trichoplusia ni Δ9 desaturase (Tni-Z9). The Z10-desaturase (Pocto-Z10) cDNA spans 2777 nt with an ORF encoding a protein with 356 amino acids. Pocto-Z10 shows lower identity to Pocto-Z9 and Tni-Z9 (48 and 46%, respectively) and relatively higher identity to the Δ11 desaturases of T. ni and Helicoverpa zea (57 and 56%, respectively). The ORFs of these two P. octo cDNAs were constructed into an expression vector, YEpOLEX, that complemented the unsaturated fatty acid (UFA) auxotrophy of a desaturase-deficient ole1 strain of Saccharomyces cerevisiae. Expression of Pocto-Z9 produced a 5:2 ratio of Z9–16 and Z9–18 acids, with minor amounts (<4%) of Z9–14, Z9–15, and Z9–17 acids. Pocto-Z10 was successfully expressed in the YEpOLEX system when complemented with Z11–18:Me, and the major desaturase product proved to be Z10–16:Acid. The results confirm the regio- and stereo-selectivity of this unusual Δ10 desaturase.