A multifunctional desaturase involved in the biosynthesis of the processionary moth sex pheromone

doi:10.1073/pnas.0705385104

A multifunctional desaturase involved in the biosynthesis of the processionary moth sex pheromone

*Research Unit on BioActive Molecules (RUBAM), Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, and
^†Departament de Biologia Molecular i Cellular, Institut de Biologia Molecular i Cellular de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Jordi Girona 18, 08034 Barcelona, Spain

Edited by Wendell Roelofs, Cornell University, Geneva, NY, and approved September 4, 2007 (received for review June 8, 2007)

Abstract

The sex pheromone of the female processionary moth, Thaumetopoea pityocampa, is a unique C16 enyne acetate that is biosynthesized from palmitic acid. Three consecutive desaturation reactions transform this saturated precursor into the triunsaturated fatty acyl intermediate: formation of (Z)-11-hexadecenoic acid, acetylenation to 11-hexadecynoic acid, and final Δ¹³ desaturation to (Z)-13-hexadecen-11-ynoic acid. By using degenerate primers common to all reported insect desaturases, a single cDNA sequence was isolated from total RNA of T. pityocampa female pheromone glands. The full-length transcript of this putative desaturase was expressed in elo1Δ/ole1Δ yeast mutants (both elongase 1 and Δ⁹ desaturase-deficient) for functional assays. The construct fully rescued the Δole1 yeast phenotype, confirming its desaturase activity. Analysis of the unsaturated products from transformed yeast extracts demonstrated that the cloned enzyme showed Δ¹¹ desaturase, Δ¹¹ acetylenase, and Δ¹³ desaturase activities. Therefore, this single desaturase may account for the three desaturation steps involved in the sex pheromone biosynthetic pathway of the processionary moth.

Footnotes

^‡To whom correspondence should be addressed. E-mail: gfdqob{at}cid.csic.es
Author contributions: M.S., B.P. and G.F. designed research; M.S. performed research; B.P. and F.C. contributed new reagents/analytic tools; M.S., B.P., J.L.A., and G.F. analyzed data; and G.F. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
Data deposition: The sequence reported in this paper has been deposited in the GenBank database (accession no. EF150363).
Abbreviations:

GC/MS,

gas chromatography coupled to mass spectrometry;

Tpi-PGFAD,

T. pityocampa pheromone gland fatty acid desaturase gene.