Project description:The Drosophila sex determination hierarchy controls all aspects of somatic sexual differentiation, including sex-specific differences in adult morphology and behavior. To gain insight into the molecular-genetic specification of reproductive behaviors and physiology, we identified genes expressed in the adult head and central nervous system that are regulated downstream of sex-specific transcription factors encoded by doublesex (dsx) and fruitless (fru). We used a microarray approach and identified 54 genes regulated downstream of dsx. Furthermore, based on these expression studies we identified new modes of DSX-regulated gene expression. We also identified 90 and 26 genes regulated in the adult head and central nervous system tissues, respectively, downstream of the sex-specific transcription factors encoded by fru. In addition, we present molecular-genetic analyses of two genes identified in our studies, calphotin (cpn) and defective probocisis response (dpr), and begin to describe their functional roles in male behaviors. We show that dpr and dpr-expressing cells are required for the proper timing of male courtship behaviors. Keywords: genetic modification
Project description:The effect of germline tissue on somatic sex-biased expression is examined. Expression is assayed in various adult tissues with germline ablated directly or genetically. The effect of germline signalling on sex-biased expression in the Drosophila head is also examined. Keywords: Expression profiling
Project description:The Drosophila sex determination hierarchy consists of a splicing cascade with sex-specific transcription directing somatic sexual dimorphism. Our understanding of this pathway, and many others, is incomplete. Here we pioneer an approach to expand our knowledge of gene regulatory networks (GRNs) by leveraging natural genetic variation. This approach is generalizable to any natural population, including humans. Two studies from Drosophila female head tissue were used – the DSPR collection (alleles from 15 natural variants) and F1-hybrid collection (alleles from heterozygotes of 75 isogenic lines crossed to w1118) – in a structural equation model (SEM) analysis. We expanded the sex hierarchy GRN by adding novel links among genes in the pathway and by adding novel genes to the pathway. A link from fruitless (fru) to Sex-lethal (Sxl) was found in both populations, which is supported by the presence of fru binding sites in the Sxl locus. The splicing factors male-specific lethal 2 and Rm62 were correctly identified as downstream targets of Sxl. There were 754 additional candidate genes for an expanded sex hierarchy GRN. These candidates were enriched for genes with sex-biased splicing and many components of the spliceosome were placed in the GRN. As with other population-genetic analyses, the number of alleles limits the number of observable interactions. Network expansion was only clear in the F1-hybrid population, which has an average of twice as many alleles as the DSPR population. Independent studies of doublesex and transformer mutants support many novel connections, including evidence for a link between the sex hierarchy and metabolism, with the inclusion of Insulin-like receptor in the sex hierarchy GRN.
Project description:The Drosophila sex determination hierarchy consists of a splicing cascade with sex-specific transcription directing somatic sexual dimorphism. Our understanding of this pathway, and many others, is incomplete. Here we pioneer an approach to expand our knowledge of gene regulatory networks (GRNs) by leveraging natural genetic variation. This approach is generalizable to any natural population, including humans. Two studies from Drosophila female head tissue were used – the DSPR collection (alleles from 15 natural variants) and F1-hybrid collection (alleles from heterozygotes of 75 isogenic lines crossed to w1118) – in a structural equation model (SEM) analysis. We expanded the sex hierarchy GRN by adding novel links among genes in the pathway and by adding novel genes to the pathway. A link from fruitless (fru) to Sex-lethal (Sxl) was found in both populations, which is supported by the presence of fru binding sites in the Sxl locus. The splicing factors male-specific lethal 2 and Rm62 were correctly identified as downstream targets of Sxl. There were 754 additional candidate genes for an expanded sex hierarchy GRN. These candidates were enriched for genes with sex-biased splicing and many components of the spliceosome were placed in the GRN. As with other population-genetic analyses, the number of alleles limits the number of observable interactions. Network expansion was only clear in the F1-hybrid population, which has an average of twice as many alleles as the DSPR population. Independent studies of doublesex and transformer mutants support many novel connections, including evidence for a link between the sex hierarchy and metabolism, with the inclusion of Insulin-like receptor in the sex hierarchy GRN. RNA sequencing was performed on mRNA derived from adult male or female heads, for a total of 9 samples. These samples included females that produce the male isoform of dsx [w/+;DsxD/dsxm+r15 (XX)], and two dsx mutants: females [w/+; dsxm+r15/dsxd+r3 (XX)] and males [w;dsxm+r15/dsxd+r3 (XY)]. Two wild type genotypes (Berlin and Canton-S) were sequenced at the same time, but have previously been published as part of GSE50515. There were at least 3 replicates from biological samples.
Project description:RNA-seq identifies genes that are regulated by SAGA deubiquitinase activity in glial nuclei of the Drosophila central nervous system during larval development