Genetic basis of wing morphogenesis in Drosophila: sexual dimorphism and non-allometric effects of shape variation

CARREIRA VALERIA; SOTO IGNACIO; JULIÁN MENSCH; FANARA JUAN JOSÉ

BMC DEVELOPMENTAL BIOLOGY

BIOMED CENTRAL LTD

Año: 2011 vol. 11 p. 1 - 50

1471-213X

BackgroundThe Drosophila wing represents a particularly appropriate model to investigate thedevelopmental control of phenotypic variation. Previous studies which aimed toidentify candidate genes for wing morphology demonstrated that the genetic basis ofwing shape variation in D. melanogaster is composed of numerous genetic factorscausing small, additive effects. In this study, we analyzed wing shape in males andfemales from 191 lines of D. melanogaster, homozygous for a single P-elementinsertion, using geometric morphometrics techniques. The analysis allowed us toidentify known and novel candidate genes that may contribute to the expression ofwing shape in each sex separately and to compare them to candidate genes affectingwing size which have been identified previously using the same lines.ResultsOur results indicate that more than 63% of induced mutations affected wing shape inone or both sexes, although only 33% showed significant differences in both malesand females. The joint analysis of wing size and shape revealed that only 19% of theP-element insertions caused coincident effects on both components of wing form inone or both sexes. Further morphometrical analyses revealed that the intersectionbetween veins showed the smallest displacements in the proximal region of the wing.Finally, we observed that mutations causing general deformations were more commonthan expected in both sexes whereas the opposite occurred with those generating localchanges. For most of the 94 candidate genes identified, this seems to be the firstrecord relating them with wing shape variation.ConclusionsOur results support the idea that the genetic architecture of wing shape is complexwith many different genes contributing to the trait in a sexually dimorphic manner.This polygenic basis, which is relatively independent from that of wing size, iscomposed of genes generally involved in development and/or metabolic functions,especially related to the regulation of different cellular processes such as motility,adhesion, communication and signal transduction. This study suggests thatunderstanding the genetic basis of wing shape requires merging the regulation of veinpatterning by signalling pathways with processes that occur during wing developmentat the cellular level.