Expression and evolution of delta9 and delta11 desaturase genes in the moth Spodoptera littoralis.
Desaturation of fatty acids is a key reaction in the biosynthesis of moth sex pheromones. The main component of Spodoptera littoralis sex pheromone blend is produced by the action of Delta11 and Delta9 desaturases. In this article, we report on the cloning of four desaturase-like genes in this species: one from the fat body (Sls-FL1) and three (Sls-FL2, Sls-FL3 and Sls-FL4) from the pheromone gland. By means of a computational/phylogenetic method, as well as functional assays, the desaturase gene products have been characterized. The fat body gene expressed a Delta9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1:4.5) ratio, whereas the pheromone gland Sls-FL2 expressed a Delta9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1.5:1) ratio. Although both Delta9 desaturases produced (Z)-9-tetradecenoic acid from myristic acid, transformed yeast grown in the presence of a mixture of myristic and (E)-11-tetradecenoic acids produced (Z,E)-9,11-tetradecadienoic acid, but not (Z)-9-tetradecenoic acid. The Sls-FL3 gene expressed a protein that produced a mixture of (E)-11-tetradecenoic, (Z)-11-tetradecenoic, (Z)-11-hexadecenoic and (Z)-11-octadecenoic acids in a 5:4:60:31 ratio. Despite having all the characteristics of a desaturase gene, no function could be found for Sls-FL4.
Rodríguez
Sergio
S
Department of Biological Organic Chemistry, IIQAB-CSIC, IBMB-CSIC, Jordi Girona 18, 08034 Barcelona, Spain.
Hao
Guixia
G
Liu
Weitian
W
Piña
Benjamín
B
Rooney
Alejandro P
AP
Camps
Francisco
F
Roelofs
Wendell L
WL
Fabriàs
Gemma
G
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D019143:Evolution, Molecular; D005216:Fat Body / Q000201:enzymology; D044943:Fatty Acid Desaturases / Q000096:biosynthesis* / Q000235:genetics*; D005227:Fatty Acids / Q000378:metabolism; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis; D012724:Sex Attractants / Q000096:biosynthesis; D018411:Spodoptera / Q000201:enzymology / Q000235:genetics*; D013230:Stearoyl-CoA Desaturase / Q000096:biosynthesis* / Q000235:genetics*
D018076:DNA, Complementary; D005227:Fatty Acids; D011994:Recombinant Proteins; D012724:Sex Attractants; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase