John True

John True joined the department in September 2001 and is in the process of setting up his laboratory. John is interested in the genetic basis of differences among closely related species and how natural selection brings these differences about. His work centers on Drosophila melanin patterning as a genetic and developmental model system. Planned and ongoing experimental approaches in the lab include (1) developmental genetic manipulations using strains bearing gain and loss of function mutations in genes in the dopamine pathway, which produces melanin precursors, (2) screening for and characterizing novel mutations affecting melanin pigmentation in Drosophila melanogaster, (3) using tools developed in D. melanogaster to investigate the developmental basis of male-specific wing melanin patterns in several Asian species of the Drosophila melanogaster group, (4) using genomic and proteomic techniques to elucidate the genetic and physiological basis of melanistic polymorphisms, which are very common in insects, (5) using artificial selection experiments to determine the types and amounts of genetic variation in melanin pigmentation present in nature and the potential dynamics of their responses to selection, and (6) characterizing male courtship behavior in Asian Drosophila melanogaster group species and investigating the role of male-specific wing patterns in this behavior. Because intra and interspecific variation in melanin patterns occur throughout insects and other groups of animals, insights gained from studying these Drosophila models will be useful in understanding the genetic and evolutionary mechanisms by which many types of morphological traits have diversified.

Selected Publications

• True, J.R. J. Liu, L.F. Stam, Z.B. Zeng, and C.C. Laurie 1997 Quantitative genetic analysis of divergence in male secondary sexual traits between Drosophila simulans and Drosophila mauritiana. Evolution 51:816-832.
• True, J.R., K.A. Edwards, D. Yamamoto, and S.B. Carroll. 1999 Drosophila wing melanin patterns form by vein-dependent elaboration of enzymatic prepatterns. Current Biology 9:1382-1391.
• True, J.R., Kopp, A., and Carroll, SB. 2001 Prophenoloxidase as a reporter of gene expression in Drosophila. Biotechniques 30:1004-1009
• True, J.R. and Haag. E.S. 2001 Developmental system drift and flexibility in evolujtionary trajectories. 2001 Evol. Devel. 2:109-119.
• Haag. E.S. and True, J.R. 2001 From mutants to mechanisms? Assessing the candidate gene paradigm in evolutionary biology. Evolution 55:1077-1084