Quantitative genetic analysis of natural variation in developmental time in Drosophila melanogaster second chromosome

MENSCH JULIÁN; CARREIRA VALERIA; LAVAGNINO NICOLÁS; IMBERTI MARCOS; HASSON ESTEBAN; FANARA JUAN JOSÉ

Ribeirão Preto, San Pablo, Brasil.

Simposio; V Simpósio de Ecologia, Genética e Evolução de Drosophila.; 2007

Sociedad Brasilera de Genética

Quantitative genetic analysis of natural variation in developmental timein Drosophila melanogaster second chromosome.Mensch J., Carreira V., Lavagnino N., Imberti M., Hasson E. & Fanara J.J.Laboratorio de Evolución. Departamento de Ecología, Genética & Evolución. Facultad de Ciencias Exactas yNaturales. Universidad de Buenos Aires. ArgentinaDevelopmental time (DT) is a quantitative growth trait with great variability among andwithin Drosophila species. Of the known metabolic pathways involving growth factors, theinsulin-signalling pathway emerges as the primary one for both cell proliferation and cellgrowth with remarkable conservation across animal taxa. Dissecting genetic naturalvariation for DT is a challenging goal in the way to understand the genetic architecture ofthis complex fitness-related character. In previous studies we found latitudinal variation ofDT in D. melanogaster Argentinean natural populations. Genetic factors affecting DTvariation are widespread along Drosophila genome. However, it has been suggested thatmany control growth genes mapped in chromosome 2 are particularly involved in theexpression of the trait, and presumably linked to natural cosmopolitan inversions. In thissense, we performed a quantitative genetic analysis in 70 isogenic second chromosomelines of 9 populations along a latitudinal gradient in western Argentina. Our results showgreat genetic variation within populations, establishing a first step towards the dissection ofDT natural variation. The next step of the project is aiming to elucidate the association ofthe most common cosmopolitan inversions of chromosome 2 with DT variability.