New Components of Drosophila Leg Development Identified through Genome Wide Association Studies

Abstract

The adult Drosophila melanogaster body develops from imaginal discs, groups of cells set-aside during embryogenesis and expanded in number during larval stages. Specification and development of Drosophila imaginal discs have been studied for many years as models of morphogenesis. These studies are often based on mutations with large developmental effects, mutations that are often lethal in embryos when homozygous. Such forward genetic screens can be limited by factors such as early lethality and genetic redundancy. To identify additional genes and genetic pathways involved in leg imaginal disc development, we employed a Genome Wide Association Study utilizing the natural genetic variation in leg proportionality found in the Drosophila Genetic Reference Panel fly lines. In addition to identifying genes already known to be involved in leg development, we identified several genes involved in pathways that had not previously been linked with leg development. Several of the genes appear to be involved in signaling activities, while others have no known roles at this time. Many of these uncharacterized genes are conserved in mammals, so we can now begin to place these genes into developmental contexts. Interestingly, we identified five genes which, when their function is reduced by RNAi, cause an antenna-to-leg transformation. Our results demonstrate the utility of this approach, integrating the tools of quantitative and molecular genetics to study developmental processes, and provide new insights into the pathways and networks involved in Drosophila leg development.

A single-cell transcriptome atlas of the adult muscle precursors uncovers early events in fiber-type divergence inDrosophila

“…Thus, the approximate location of Epi_13 was near the presumptive scutum in the lateral heminotum (near scutellum) and Epi_14 was likely in the posterior lateral heminotum (near scutum). Epi_7 approximate location was near the postnotum in the posterior heminotum since the expression of Epi_7 marker disco-r is restricted to the ventral edge of the wing (Grubbs et al, 2013) and the expression of another Epi_7 marker disco is restricted to the region giving rise to the post-alar bristles near the presumptive lateral scutum (Cohen et al, 1991).…”

Genetic dissection of intraspecific variation in a male-specific sexual trait in Drosophila melanogaster

“…disco-r is present within the interval implicated by X-linked QTL Q1, was shown to have lower expression in male compared with female pupal forelegs (Barmina et al , 2005) and has been suggested to be involved in leg development (Grubbs et al , 2013). pUf68 is implicated by QTL Q2 on chromosome 3.…”

The Drosophila genesdisconnectedanddisco-relatedtogether specify development of adult legs

“…Note, tub-Gal80 ts was not required to pass embryogenesis with Act-Gal4; however, we followed the same timing for elevating the temperature with the Act-Gal4 and Dll-Gal4 larvae. Others and we have noted a slight affect on leg development with the Dll-Gal4 driver since the Gal4 insertion compromises the Dll gene (Calleja et al, 1996;Grubbs et al, 2013). This was taken into account in all analyses.…”