Similar Datasets
Project description:Malaria-transmitting mosquitoes are extremely sexually dimorphic in their anatomy and behaviour. Sex-specific gene expression in Anopheles gambiae is well-studied in adult stages, but its onset during embryogenesis, apart from sex-determination factors like Yob, remains largely unknown. Here, we report a comprehensive single-embryo transcriptome atlas of A. gambiae males and females to understand the earliest stages of establishing the sex-specific expression networks. Our dataset reveals embryonic RNA isoform diversity including a global shift towards distal alternative polyadenylation (APA) events sites during the maternal-to-zygotic genome transition. Sex-biased gene expression and alternative splicing are limited during embryogenesis, with most sex-specific patterns emerging post-embryonically. X chromosome dosage compensation is established shortly after zygotic genome activation concomitant with direct binding of the master regulator protein SOA to X-linked promoters. Unlike the dosage compensation regulators in Drosophila or mammals, SOA operates in a one-step fashion, directly binding CA-rich promoter motifs without prioritizing certain gene groups over others. We propose that the Anopheles dosage compensation system represents an evolutionary endpoint of a gene-by-gene regulatory mechanism that evolved to a chromosome-wide scale.
2024-12-20 | GSE285040 | GEO
Project description:Malaria-transmitting mosquitoes are extremely sexually dimorphic in their anatomy and behaviour. Sex-specific gene expression in Anopheles gambiae is well-studied in adult stages, but its onset during embryogenesis, apart from sex-determination factors like Yob, remains largely unknown. Here, we report a comprehensive single-embryo transcriptome atlas of A. gambiae males and females to understand the earliest stages of establishing the sex-specific expression networks. Our dataset reveals embryonic RNA isoform diversity including a global shift towards distal alternative polyadenylation (APA) events sites during the maternal-to-zygotic genome transition. Sex-biased gene expression and alternative splicing are limited during embryogenesis, with most sex-specific patterns emerging post-embryonically. X chromosome dosage compensation is established shortly after zygotic genome activation concomitant with direct binding of the master regulator protein SOA to X-linked promoters. Unlike the dosage compensation regulators in Drosophila or mammals, SOA operates in a one-step fashion, directly binding CA-rich promoter motifs without prioritizing certain gene groups over others. We propose that the Anopheles dosage compensation system represents an evolutionary endpoint of a gene-by-gene regulatory mechanism that evolved to a chromosome-wide scale.
2024-12-20 | GSE285041 | GEO
Project description:In many species, males and females display differences in their physiology that are not limited to the gonads. Sex differences in adult insects can comprise body size and feeding behaviour, as only female, but not male mosquitoes are blood-feeding in order to produce eggs. This is relevant since the malaria-causing parasite Plasmodium is transmitted by a female mosquito through a previous blood meal from an infected individual. The initiation of sex-specific developmental programs can be often linked to heteromorphic sex chromosomes (XX/XY in Anopheles). In males, the X-linked genes are only present in a single copy. To counteract this hemizygosity, Anopheles, like other species, exhibits dosage compensation (DC). Anopheles DC manifests by upregulation of the single male X ensuring the equal expression of sex-chromosomal genes between males and females. To date, the sex-specific differences at the transcriptome level related to the X/Y chromosomes and DC have been characterized at post-embryonic stages. Their onset during embryogenesis, especially during the early stages where the embryo switches from the maternal to the zygotic transcriptome, is largely uncharacterized to date. Here, we generate a sex-specific transcriptome atlas across Anopheles embryogenesis ending at the first larval stage. Along with the transition from the maternal to the zygotic transcriptome, many transcripts switch isoform, where the 3’ untranslated regions (UTR) of zygotic transcripts are significantly extended compared to their maternal counterpart. We also identify stage- and sex-specific splicing events. Comparing male and female embryos, we identify 120 sexually dimorphic protein coding genes and non-coding RNAs, indicating that sexually dimorphic gene expression is not widespread during embryogenesis. Furthermore, the imbalance of X-linked genes between males and females after zygotic genome activation is corrected shortly after, where the majority of genes exhibit DC around 9 hours of embryogenesis with further fine-tuning later in development. Our atlas provides a framework to explore sex differences in development and evolution and thereby, enables future functional analyses of sex-specific expression patterns and isoform usage.
2023-07-25 | GSE210624 | GEO
Project description:Sex-specific transcriptome dynamics of Anopheles gambiae during embryonic development
| PRJNA1201096 | ENA
Project description:Sex-specific transcriptome of Anopheles gambiae during embryonic development
| PRJNA866506 | ENA
Project description:Sex-specific transcriptome dynamics of Anopheles gambiae during embryonic development [RNA-seq]
| PRJNA1201102 | ENA
Project description:Sex-specific transcriptome dynamics of Anopheles gambiae during embryonic development [CUT&Tag]
| PRJNA1201103 | ENA
Project description:BackgroundThe midgut of hematophagous insects, such as disease transmitting mosquitoes, carries out a variety of essential functions that mostly relate to blood feeding. The midgut of the female malaria vector mosquito Anopheles gambiae is a major site of interactions between the parasite and the vector. Distinct compartments and cell types of the midgut tissue carry out specific functions and vector borne pathogens interact and infect different parts of the midgut.ResultsA microarray based global gene expression approach was used to compare transcript abundance in the four major female midgut compartments (cardia, anterior, anterior part of posterior and posterior part of posterior midgut) and between the male and female Anopheles gambiae midgut. Major differences between the female and male midgut gene expression relate to digestive processes and immunity. Each compartment has a distinct gene function profile with the posterior midgut expressing digestive enzyme genes and the cardia and anterior midgut expressing high levels of antimicrobial peptide and other immune gene transcripts. Interestingly, the cardia expressed several known anti-Plasmodium factors. A parallel peptidomic analysis of the cardia identified known mosquito antimicrobial peptides as well as several putative short secreted peptides that are likely to represent novel antimicrobial factors.ConclusionThe A. gambiae sex specific midgut and female midgut compartment specific transcriptomes correlates with their known functions. The significantly greater functional diversity of the female midgut relate to hematophagy that is associated with digestion and nutrition uptake as well as exposes it to a variety of pathogens, and promotes growth of its endogenous microbial flora. The strikingly high proportion of immunity related factors in the cardia tissue most likely serves the function to increase sterility of ingested sugar and blood. A detailed characterization of the functional specificities of the female mosquito midgut and its various compartments can greatly contribute to our understanding of its role in disease transmission and generate the necessary tools for the development of malaria control strategies.
| S-EPMC1804276 | biostudies-literature
Project description:The understanding of the molecular mechanisms of sex differentiation in the mosquito Anopheles gambiae could identify important candidate genes for inducing selective male sterility in transgenic lines or for sex-controlled expression of lethal genes. In many insects, doublesex (dsx) is the double-switch gene at the bottom of the somatic sex-determination cascade that determines the differentiation of sexually dimorphic traits. We report here on the identification of the dsx homologue in A. gambiae and on the characterization of its sex-specific transcripts. Agdsx consists of seven exons, distributed over an 85 kb region on chromosome 2R, which are sex-specifically spliced to produce the female and male AgdsxF and AgdsxM transcripts. AgdsxF contains a 795 bp ORF, coding for a protein of 265 amino acids, while AgdsxM comprises a much longer (1866 bp) ORF, coding for a 622 aa protein. Differences in the exon/intron organization suggest that Agdsx sex-specific splicing results from a different mechanism from Drosophila melanogaster dsx. These findings represent an important step towards the understanding of sex differentiation in Anopheles and will facilitate the use of gene transfer technologies to manipulate sex ratios for vector control programs based on the sterile insect technique.
| S-EPMC1350936 | biostudies-literature
Project description:BACKGROUNDChemosensory signal transduction guides the behavior of many insects, including Anopheles gambiae, the major vector for human malaria in sub-Saharan Africa. To better understand the molecular basis of mosquito chemosensation we have used whole transcriptome RNA sequencing (RNA-seq) to compare transcript expression profiles between the two major chemosensory tissues, the antennae and maxillary palps, of adult female and male An. gambiae.RESULTSWe compared chemosensory tissue transcriptomes to whole body transcriptomes of each sex to identify chemosensory enhanced genes. In the six data sets analyzed, we detected expression of nearly all known chemosensory genes and found them to be highly enriched in both olfactory tissues of males and females. While the maxillary palps of both sexes demonstrated strict chemosensory gene expression overlap, we observed acute differences in sensory specialization between male and female antennae. The relatively high expression levels of chemosensory genes in the female antennae reveal its role as an organ predominately assigned to chemosensation. Remarkably, the expression of these genes was highly conserved in the male antennae, but at much lower relative levels. Alternatively, consistent with a role in mating, the male antennae displayed significant enhancement of genes involved in audition, while the female enhancement of these genes was observed, but to a lesser degree.CONCLUSIONSThese findings suggest that the chemoreceptive spectrum, as defined by gene expression profiles, is largely similar in female and male An. gambiae. However, assuming sensory receptor expression levels are correlated with sensitivity in each case, we posit that male and female antennae are perceptive to the same stimuli, but possess inverse receptive prioritizations and sensitivities. Here we have demonstrated the use of RNA-seq to characterize the sensory specializations of an important disease vector and grounded future studies investigating chemosensory processes.
| S-EPMC3126782 | biostudies-literature