Pheromone gland-specific fatty-acyl reductase of the silkmoth, Bombyx mori

doi:10.1073/pnas.1531993100

Pheromone gland-specific fatty-acyl reductase of the silkmoth, Bombyx mori

^*RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198, Japan; ^†Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan; and ^‡Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan

Edited by Wendell Roelofs, Cornell University, Geneva, NY, and approved June 3, 2003 (received for review April 9, 2003)

Abstract

The C₁₀-C₁₈ unsaturated, acyclic, aliphatic compounds that contain an oxygenated functional group (alcohol, aldehyde, or acetate ester) are a major class of sex pheromones produced by female moths. In the biosynthesis of these pheromone components, the key enzyme required to produce the oxygenated functional groups is fatty-acyl reductase (FAR). This enzyme converts fatty-acyl pheromone precursors to their corresponding alcohols, which, depending on the moth species, can then be acetylated or oxidized to the corresponding aldehydes. Despite the significant role this enzyme has in generating the species-specific oxygenated constituents of lepidopteran sex pheromones, the enzyme has yet to be fully characterized and identified. In experiments designed to characterize a pheromone-gland-specific FAR in the silkmoth, Bombyx mori, we have isolated a cDNA clone encoding a protein homologous to a FAR from the desert shrub, Simmondsia chinensis, commonly known as jojoba. The deduced amino acid sequence of this clone predicts a 460-aa protein with a consensus NAD(P)H binding motif within the amino terminus. Northern blot analysis indicated that 2-kb transcripts of this gene were specifically expressed in the pheromone gland at 1 day before adult eclosion. Functional expression of this gene in the yeast Saccharomyces cerevisiae not only confirmed the long-chain FAR activity, but also indicated a distinct substrate specificity. Finally, the transformed yeast cells evoked typical mating behavior in male moths when cultured with the pheromone precursor fatty acid, (E,Z)-10,12-hexadecadienoic acid.

Footnotes

↵ § To whom correspondence should be addressed. E-mail: smatsu{at}postman.riken.go.jp.
This paper was submitted directly (Track II) to the PNAS office.
Abbreviations: FAR, fatty-acyl reductase; JJFAR, jojoba FAR; pgFAR, pheromone-gland FAR; HMG-CoA, 3-hydroxy-3-methylglutaryl CoA; PBAN, pheromone biosynthesis-activating neuropeptide.
Data deposition: The sequences reported in this paper have been deposited in the GenBank database (accession nos. AB104896 and AB104897 for Bombyx mori pgFAR).