Project description:We performed genome-wide expression assays comparing gene expression in the Drosophila melanogaster third larval instar genital imaginal disc between males and females. We used microarrays to compare the relative expression levels of five independent male versus female comparisons for each of two different D. melanogaster wild-type strains, Canton-S and Berlin. All microarrays were dual channel direct comparisons of late third larval instar male versus female genital imaginal discs from two Drosophila melanogaster wildtype strains, Canton S and Berlin. For each strain five independent biological samples were analyzed using a dye-swap design (i.e. male samples labeled with Cy5 in three replicates were labeled with Cy3 in the other two replicates in that experimental set).
Project description:Deep sequencing of total RNA extracted from the genital discs of males for each of the following strains : Drosophila sechellia, Drosophila mauritiana, hybrid introgression line 3Q1(A) and hybrid introgression line Q1(A)
Project description:Deep sequencing of total RNA extracted from the genital discs of males for each of the following strains : Drosophila sechellia, Drosophila mauritiana, hybrid introgression line 3Q1(A) and hybrid introgression line Q1(A) Analysis of poly(A)+ RNA for three independent biological replicates of sequencing libraries for each of the following strains: D. sechellia w, D. mauritiana P-insertion Q1, hybrid introgression line 3Q1(A), and hybrid introgression line Q1(A). Male genital discs were obtained as described above, and total RNA was extracted using RNAqueousM-CM-^BM-BM-.-Micro Kit (Ambion). Poly(A)+ transcripts were isolated subsequently using MicroPoly(A)PuristM-CM-"M-BM-^DM-BM-" Kit (Ambion). To facilitate normalization of reads across our samples, at this stage of library construction we spiked-in small amounts of exogenous RNA from ArrayControlM-CM-"M-BM-^DM-BM-" Kit (Ambion) into each sample of poly(A)+ RNA. Paired-end sequencing was carried out by loading the samples onto four lanes (three samples per lane) of a flow cell and run on an Illumina Genome Analyzer IIx sequencer using 72 cycles per end of each paired-end read. Biological replicates of each genotype were loaded onto separate lanes.
Project description:We performed genome-wide expression assays comparing gene expression in the Drosophila melanogaster third larval instar genital imaginal disc between males and females. We used microarrays to compare the relative expression levels of five independent male versus female comparisons for each of two different D. melanogaster wild-type strains, Canton-S and Berlin.
Project description:Background: Studying genomic variation in rapidly evolving pathogens potentially enables definition of genes supporting their “core biology” present, functional and expressed by all strains or “flexible biology”, varying between strains. Genes supporting flexible biology may be considered to be “accessory”, whilst the “core” gene set is likely to be important for common features of a pathogen species biology, including virulence on all host genotypes. The wheat-pathogenic fungus Zymoseptoria tritici represents one of the most rapidly evolving threats to global food security and was the focus of this study. Results:We constructed a pangenome of 18 European field isolates, with 12 also subjected to RNAseq transcription profiling during infection. Combining this data, we predicted a “core” gene set comprising 9807 sequences which were; (1) present in all isolates; (2) lacking inactivating polymorphisms ; and (3) expressed by all isolates. A large accessory genome, consisting of 45% of the total genes was also defined. We classified genetic and genomic polymorphism at both chromosomal and individual gene scales. Proteins required for essential functions including virulence, had lower-than average sequence variability amongst core genes. Both core and accessory genomes encoded many small, secreted candidate effector proteins that likely interact with plant immunity. Viral vector-mediated transient in planta overexpression of 88 candidates failed to identify any which induced leaf necrosis characteristic of disease. However, functional complementation of a non-pathogenic deletion mutant lacking five core genes, demonstrated that full virulence was restored by re-introduction of the single gene exhibiting least sequence polymorphism and highest expression. Conclusions:These data support the combined use of pangenomics and transcriptomics for defining genes which represent core, and potentially exploitable, weaknesses in rapidly evolving pathogens.
Project description:Female Aedes aegypti mosquitoes impose a severe global public health burden as primary vectors of multiple viral and parasitic pathogens. Under optimal environmental conditions, Aedes aegypti females have access to human hosts that provide blood proteins for egg development, conspecific males that provide sperm for fertilization, and freshwater that serves as an egg-laying substrate suitable for offspring survival. As global temperatures rise, Aedes aegypti females are faced with climate challenges, like intense droughts and intermittent precipitation, which create unpredictable and suboptimal conditions for the egg-laying step of their reproductive cycle. Aedes aegypti mosquitoes nonetheless show remarkable reproductive resilience, but how they achieve this is unknown. Here we show that under drought-like conditions simulated in the laboratory, mated, blood-fed Aedes aegypti females carrying mature eggs retain them in their ovaries for extended periods, while maintaining the viability of these eggs until they can be deposited in freshwater. Using transcriptomic and proteomic profiling of Aedes aegypti ovaries, we identify two previously uncharacterized genes – here named tweedledee and tweedledum – that show ovary-enriched, temporally-restricted expression during egg retention. These genes are mosquito-specific, linked within a syntenic locus, and rapidly evolving under positive selection, raising the possibility that they serve an adaptive function. Using loss-of-function mutagenesis to disrupt both genes, we show that, tweedledee and tweedledum, which encode secreted proteins, are specifically required for extended retention of viable eggs, such as during intermittent precipitation or drought. These results highlight an elegant example of taxon-restricted genes at the heart of an important adaptation that equips Aedes aegypti females with “insurance” to, when contextually appropriate, flexibly extend their reproductive sequence without losing reproductive capacity, thus allowing this species to exploit diverse and unpredictable/chaotic/changing habitats.
Project description:This SuperSeries is composed of the following subset Series: GSE3871: Effects of androgen treatment on genital fibroblasts GSE3872: Baseline gene transcription in genital fibroblasts Abstract: BACKGROUND: Androgen insensitivity syndrome (AIS) comprises a range of phenotypes from male infertility to complete feminization. Most individuals with AIS carry germline mutations of the androgen receptor (AR) that interfere with or ablate its function. As genital fibroblasts retain expression of the AR in vitro, we used genital skin fibroblasts from normal males and 46,XY females with complete AIS due to known AR mutations to gain insights into the role of the AR in human genital differentiation. RESULTS: Using DNA microarrays representing 32,968 different genes, we identified 404 transcripts with significant differences in transcription levels between genital skin fibroblasts cultured from normal and AIS-affected individuals. Gene-cluster analyses uncovered coordinated expression of genes involved in key processes of morphogenesis. On the basis of animal studies and human genetic syndromes, several of these genes are known to have specific roles in genital differentiation. Remarkably, genital fibroblasts from both normal and AIS-affected individuals showed no transcriptional response to dihydrotestosterone treatment despite expression of the AR. CONCLUSIONS: The results suggest that in addition to differences in the anatomic origin of the cells, androgen signaling during prenatal development contributes to setting long-lasting, androgen-independent transcriptional programs in genital fibroblasts. Our findings have broad implications in understanding the establishment and the stability of sexual dimorphism in human genital development. Refer to individual Series