Mark D. Drapeau (Department of Biology, New York University)

Published in bio.philica.com

Observation
Recent work has concentrated on the role of the yellow gene in the pleiotropic regulation of both pigmentation and behavior in the fly Drosophila melanogaster (e.g. Wittkopp et al. 2002, Drapeau et al. 2003). The yellow-dependent pigmentation and behavior are both sex-specific in this species. A logical hypothesis is that the sex-specificity is achieved in part because of yellow regulation by the well-characterized sex-determination pathway. Indeed, for the case of male courtship behavior, yellow brain expression is controlled by the sexual transcription factor fruitless (Drapeau et al. 2003). More specifically, the fru[3] mutant, lacking the zinc-finger portion of the FRU protein required for transcription regulation, cannot regulate yellow male brain expression (Drapeau et al. 2003).

Examination of fru[3] pigment revealed a wild-type phenotype. All pigmented structures such as the body cuticle and aristae appeared to have normal levels of yellow-dependent melanin, in comparison to fru[3] heterozygotes and wild-type flies. This suggests that while FRU sex-specifically regulates yellow in the brain, it does not do so in the cuticle.

This observation is consistent with the fact that fru expression is to date only known in the central and peripheral nervous systems (Stockinger et al. 2005). Hence, the yellow-dependent pigmentation of fru[3] flies provides additional evidence for this, and suggests that other sex-determination genes, such as doublesex (dsx), are involved in yellow regulation with respect to sex-specific pigmentation. Indeed, yellow might have DSX binding sites upstream of its transcription start (Drapeau et al. 2006).

Observation circumstances
This laboratory observation is part of a larger body of work on the role of the yellow gene in the regulation of pigmentation and behavior of Drosophila melanogaster, including the author’s doctoral dissertation.

References
Drapeau, M. D., Radovic, A., Wittkopp, P. J., & Long, A. D. (2003). A gene necessary for normal male courtship, yellow, acts downstream of fruitless in the Drosophila melanogaster larval brain. Journal of Neurobiology, 55, 53-72.

Drapeau, M. D., Cyran, S. A., Viering, M. M., Geyer, P. K., & Long, A. D. (2006). A cis-regulatory sequence within the yellow locus of Drosophila melanogaster required for normal male mating success. Genetics, 172, 1009-1030.

Stockinger, P., Kvitsiani, D., Rotkopf, S., Tirian, L., & Dickson, B. J. (2005). Neural circuitry that governs Drosophila male courtship behavior. Cell, 121, 795-807.

Wittkopp, P. J., True, J. R., & Carroll, S. B. (2002). Reciprocal functions of the Drosophila yellow and ebony proteins in the development and evolution of pigment patterns. Development, 129, 1849-1858.

Information about this Observation
This Observation has not yet been peer-reviewed
This Observation was published on 29th June, 2006 at 23:20:32 and has been viewed 4813 times.

This work is licensed under a Creative Commons Attribution 2.5 License.

The full citation for this Observation is: Drapeau, M. (2006). FRU does not regulate yellow in fly pigmented cells. PHILICA.COM Observation number 13.