The role of desaturases in the biosynthesis of marking pheromones in bumblebee males

0395109 - ÚOCHB 2014 RIV GB eng J - Journal Article
Buček, Aleš - Vogel, H. - Matoušková, Petra - Prchalová, Darina - Žáček, Petr - Vrkoslav, Vladimír - Šebesta, Petr - Svatoš, Aleš - Jahn, Ullrich - Valterová, Irena - Pichová, Iva
The role of desaturases in the biosynthesis of marking pheromones in bumblebee males.
Insect Biochemistry and Molecular Biology. Roč. 43, č. 8 (2013), s. 724-731. ISSN 0965-1748. E-ISSN 1879-0240
R&D Projects: GA ČR GA203/09/1446
Institutional support: RVO:61388963
Keywords : fatty acid desaturase * bumblebee * Hymenoptera * pheromone * RNA-seq * functional expression
Subject RIV: CE - Biochemistry
Impact factor: 3.420, year: 2013

Bumblebee males (Hymenoptera) produce species-specific labial gland secretions called marking pheromones (MPs). MPs generally consist of terpenoids and fatty-acid-derived aliphatic compounds with various chain lengths predominantly containing one or no double bonds. The unsaturated fatty-acid-derived MP components were hypothesized to be produced by fatty acid desaturases (FADs) that exhibit diverse substrate specificities. To address this hypothesis, we isolated and functionally characterized FADs from three bumblebee species: Bombus lucorum, Bombus terrestris, and Bombus lapidarius. By employing RNA sequencing of the male labial glands and fat bodies of B. lucorum and B. terrestris, we identified five paralogous FAD-like sequences but only two FAD lineages were abundant and differentially expressed in the labial glands. We found that abundant FAD lineages were also expressed in the labial gland and fat body of Bombus lapidarius. Functional characterization of FADs in a yeast expression system confirmed that Delta 4-FADs exhibited a unique Delta 4-desaturase activity exclusively on 14-carbon fatty acyls and Delta 9-FADs displayed Delta 9-desaturase activity on 14- to 18-carbon fatty acyls. These results indicate that Delta 9-FADs are involved in the biosynthesis of major unsaturated components of MPs in B. lucorum and B. lapidarius despite the diverse MP composition of these bumblebee species. The contribution of lipases, acyltransferases, esterases, and fatty acid reductases to production of the species-specific MP composition is also discussed in light of the transcriptomic data obtained in this study.
Permanent Link: http://hdl.handle.net/11104/0223273