Table of Contents
International Journal of Evolutionary Biology
Volume 2009, Article ID 291236, 9 pages
http://dx.doi.org/10.4061/2009/291236
Research Article

Hormones and Sex-Specific Transcription Factors Jointly Control Yolk Protein Synthesis in Musca domestica

1Zoological Institute, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
2Department of Genetics and Molecular Biology, University of Szeged, Közép fasor 52, 6724 Szeged, Hungary
3Institute of Molecular Biology, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland

Received 27 March 2009; Revised 6 July 2009; Accepted 12 August 2009

Academic Editor: Yoko Satta

Copyright © 2009 Christina Siegenthaler et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In the housefly Musca domestica, synthesis of yolk proteins (YPs) depends on the level of circulating ecdysteroid hormones. In female houseflies, the ecdysterone concentration in the hemolymph oscillates and, at high levels, is followed by expression of YP. In male houseflies, the ecdysterone titre is constantly low and no YP is produced. In some strains, which are mutant in key components of the sex-determining pathway, males express YP even though their ecdysterone titre is not significantly elevated. However, we find that these males express a substantial amount of the female variant of the Musca doublesex homologue, Md-dsx. The dsx gene is known to sex-specifically control transcription of yp genes in the fat body of Drosophila melanogaster. Our data suggest that Md-dsx also contributes to the regulation of YP expression in the housefly by modulating the responsiveness of YP-producing cells to hormonal stimuli.