Project description:We have identified that miR-2b-1 of D. melanogaster causes testicular bulging (a tumour like phenotype) and hence have performed a transcriptomic analysis on these bulged testes. Adult flies overexpressing miR-2b-1 were used to perform transcriptomic analysis to identify the differentially expressed genes.
Project description:Testes and testes terminal epithelium/seminal vesicles were dissected and separated from 4-5 day old Oregon-R-modENCODE Drosophila melanogaster males. RNA-sequencing was then performed on these two distinct biological structures.
Project description:In order to study the effect of protease treatment on dissected testes, we performed different strategies of cleaning and dissociation on Drosophila melanogaster w1118 larval testes. We collected testes without protease treatment with fatbody just attached around the gonad, fatbody alone dissected from around the testes, testes without fatbody and testes dissociated by either by Papain or Trypsin and Collagenase cocktail. We prepared poly A+ RNA-Seq libraries and performed transcriptional profiling to generate 50 bp stranded single end reads.
Project description:Spermiogenesis in Drosophila melanogaster is a highly conserved process and essential for male fertility. In this haploid phase of spermatogenesis, motile sperm are assembled from round cells, flagella are assembled, and needle-shaped nuclei with highly compacted genomes are formed. We aimed at identifying proteins relevant for the maturation phase from spermatids to sperm. As transcription takes place mainly in spermatocytes, and transcripts with relevance for post-meiotic sperm development are translationally repressed for days, we comparatively analysed the prote-ome of larval testes (stages before meiotic divisions), of testes of 1–2-day-old pupae (meiotic and early spermatid stages) and adult flies (late spermatids and sperm). We identified 6677 pro-teins, with 422 solely detected in larval testes, 623 in pupal testes and 634 in adult testes. We analysed a few so far uncharacterized proteins with repect to stage specific expression and im-portance for male fertility. For example, Mst84B (gene CG1988), a very basic cysteine- and lysine-rich nuclear protein, was present in the phase of transition from a histone-based to a pro-tamine-based chromatin structure. CG6332 encodes d-Theg, which is related to the mouse tHEG and human THEG proteins. Mutants of d-Theg lacked sperm in the seminal vesicles and were sterile. The identification of numerous predicted proteins underscores the high potential of pro-teome analysis for future analyses of spermatogenesis.
Project description:miRNAs are small, non-coding RNAs that regulate gene expression post-transcriptionally. We used small RNA sequencing to identify tissue-specific miRNAs in the adult brain, thorax, gut and fat body of Drosophila melanogaster. One of the most brain-specific miRNAs that we identified was miR-210, an evolutionarily highly conserved miRNA implicated in the regulation of hypoxia in mammals. In Drosophila, we show that miR-210 is specifically expressed in sensory organs including photoreceptors. miR-210 knock-out mutants are not sensitive towards hypoxia but show progressive degradation of photoreceptor cells, accompanied by decreased photoreceptor potential, demonstrating an important function of miR-210 in photoreceptor maintenance and survival.
Project description:Genome wide localization of Kumgang, dMi-2, and Aly in Drosophila melanogaster testes were evaluated by ChIP-Seq in wild-type and kmg knock down testes. / Title: Blocking promiscuous activation at cryptic promoters directs cell type–specific gene expression / Abstract: To selectively express cell type–specific transcripts during development, it is critical to maintain genes required for other lineages in a silent state. Here, we show in the Drosophila male germline stem cell lineage that a spermatocyte-specific zinc finger protein, Kumgang (Kmg), working with the chromatin remodeler dMi-2 prevents transcription of genes normally expressed only in somatic lineages. By blocking transcription from normally cryptic promoters, Kmg restricts activation by Aly, a component of the testis-meiotic arrest complex, to transcripts for male germ cell differentiation. Our results suggest that as new regions of the genome become open for transcription during terminal differentiation, blocking the action of a promiscuous activator on cryptic promoters is a critical mechanism for specifying precise gene activation.
Project description:Whole genome expression analyses reveal little evidence for X chromosome dosage compensation or meiotic inactivation in Drosophila testes, whereas testes-specific transgene reporters suggest a novel form of X chromosome-specific regulation.