Project description:The goal of this study was to determine whether there was a direct relationship between stress and DNA methylation changes in fish gonads. During sex differentiation, we studied the sensitive window to density. Sex ratios were studied and methylation of canonical reproduction-related genes was analysed.
Project description:The aim of the experiment was to study the gene expression changes occurring when cells of the diatom Skeletonema marinoi undergo sexual reproduction. In this species, sex can be induced by an environmental trigger, specifically a change in salinity of the cultivation media. In diatoms the unique mode of cell division with unequal inheritance of the rigid cell wall components determines a progressive cell size reduction as cells divide. Large cells above a given size threshold are not competent for sex, on the other hand small cells, under appropriate conditions, can undergo sexual reproduction. RNA-seq included three experimental conditions: a) large cells above the sexualization size threshold, grown at standard salinity (control condition: no sex, no salinity stress); b) large cells above the sexualization size threshold transferred to higher salinity (treatment 1: no sex, salinity stress); c) small cells below the sexualization size threshold transferred to higher salinity (treatment 2: sex, salinity stress).
Project description:The swamp eel or rice field eel (Monopterus albus) taxonomically belongs to the family Synbranchidae of the order Synbranchiformes (Neoteleostei, Teleostei, Vertebrata). It is not only an economically important freshwater fish in aquacultural production, but also an increasingly known model species for biological studies. Understanding molecular mechanisms underlying sex change is a major area of interest. The swamp eel thus offers a powerful system for studying sexual development and adaptive evolution in vertebrates.The whole genome sequencing provides valuable resources for sex control in fish production, species protection through manipulating sex reversal genes, and potentially enabling effective population control and promoting reproduction health in human.
Project description:Sex-specific differences in gene expression underlie differences in morphology, behavior, and reproduction. To date, little is known about sex-specific differences in gene expression in spider mites, even though males and females differ markedly in morphology and behavior. In this study, we describe the complement of sex-specific gene expression differences between males and females of the two-spotted spider mite (Tetranychus urticae), an important generalist herbivore that is a significant crop pest. Gene expression differences were detected from analyses of mRNA-seq data collected with the Illumina method (eight samples in total consisting of four biological replicates each for males and females).
Project description:Sexual reproduction is nearly universal among multicellular animals, but sex can be determined by cues including sex chromosomes, temperature, social status, and photoperiod. DMRT transcription factors are key regulators of sex in animals that use diverse sex-determining strategies. These proteins are related to the sexual regulators Doublesex (Dsx) and Male abnormal-3 (MAB-3) of insects and nematodes, respectively. DMRT proteins share the DM DNA binding domain, comprised of a unique intertwined double zinc-binding module flanked by a C-terminal recognition helix that binds to a pseudopalindromic target DNA. Despite the central role of DMRT proteins in metazoan sexual development, how they recognize target DNA sequences is poorly understood. Here we find that DMRT proteins employ multiple DNA binding modes due to surprising versatility in how specific base contacts are made. Human DMRT1 can bind as a dimer, trimer or tetramer, in each case using paired antiparallel recognition helices that together insert into a widened DNA major groove to make base-specific contacts. Insertion of two helices in a single major groove is, to our knowledge, a DNA binding interaction unique to DMRT proteins. High resolution in vivo DNA binding analysis (ChIP-Exo) indicates that multiple DNA binding modes also are used in the mouse testis. Finally, we show that mutations affecting amino acid residues crucial for DNA recognition are associated with sex reversal in flies and also, for the first time, with male-to-female sex reversal in humans. Our results illuminate an ancient molecular interaction that underlies much of metazoan sexual development.
Project description:Cytosine methylation is a key epigenetic mark in many organisms, important for both transcriptional control and genome integrity. While relatively stable during somatic growth, DNA methylation is reprogrammed genome-wide during mammalian reproduction. Reprogramming is essential for zygotic totipotency, and to prevent transgenerational inheritance of epimutations. The extent of DNA methylation reprogramming in plants however remains unclear. Here, we developed sensors reporting with single-cell resolution CG and non-CG methylation in Arabidopsis. Live imaging during reproduction revealed distinct and sex-specific dynamics for both contexts. We found that CHH methylation in the egg cell depends on DRM2 and Pol V, two main actors of RNA-directed DNA methylation, but does not depend on Pol IV. Our sensors provide insight into global DNA methylation dynamics at the single cell level with high temporal resolution, and offer a powerful tool to track CG and non-CG methylation both during development and in response to environmental cues in all organisms with methylated DNA.
Project description:In our study, differential male nucleus events and development behaviors were revealed from the fertilized eggs in response to the sperm from males of genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) in gibel carp. When the eggs of maternal fish were fertilized by the sperm from males of GSD, the fertilized egg encountered similar sexual reproduction events and behaviors. However, when the eggs of maternal fish were fertilized by the sperm from males of TSD, a typical process of gynogenesis was observed. To reveal the underlying molecular mechanism of differential sperm nucleus development behaviors in the fertilized eggs, iTRAQ-based quantitative semen proteomics were performed on three semen samples from three males of GSD and three semen samples from three males of TSD respectively.
Project description:The swamp eel or rice field eel (Monopterus albus) taxonomically belongs to the family Synbranchidae of the order Synbranchiformes (Neoteleostei, Teleostei, Vertebrata). It is not only an economically important freshwater fish in aquacultural production, but also an increasingly known model species for biological studies. Understanding molecular mechanisms underlying sex change is a major area of interest. The swamp eel thus offers a powerful system for studying sexual development and adaptive evolution in vertebrates.The whole genome sequencing provides valuable resources for sex control in fish production, species protection through manipulating sex reversal genes, and potentially enabling effective population control and promoting reproduction health in human. High throughput sequencing was employed for three samples,three kind s of sex gonad from swamp eel, testis,ovotestis and ovary, no replicates.
Project description:Diverse sex determination mechanisms have been reported in eukaryotes, but little is known about the genetic pathways leading to sex determination in red algae. Sex-specific genes that could be involved in sex determination and sexual differentiation were investigated in a red alga Bostrychia moritziana by analyzing the transcriptomes of various phases including males, females and tetrasporophytes. Sex-dominantly-expressed genes which shows >10 fold difference between sexes were isolated using comparative RNA-seq analysis. We found 19 gene homologues, 10 from males and 9 from females, that were found only in one sex in genomic amplification. This suggests that these divergent homologues are on non-recombining, possibly different, chromosomes in their respective sexes. Most of the sex-specific genes are involved in important cellular processes including chromosome segregation, nucleo-cytoplasmic protein shuttling or tRNA modification. Quantitative PCR analysis also showed that some sex-specific genes were differently regulated during critical events of sexual reproduction like fertilization and carposporophyte development. We could also localize the expression of a male-specific gene in spermatia before and after gamete binding using RNA in situ hybridization. Another set of transcripts were found that were sex-dominantly-expressed, but not sex-specific. 19 out of 39 sex-dominantly-expressed transcripts were annotated to transposable elements, but none of them was sex-specific. Our results suggest that sexual differentiation in B. moritziana may be achieved by multi-level regulation of cellular processes, both from genes present only in one sex and differential expression of shared genes.
Project description:We have further tested and validated a reproduction-enriched microarray designed specifically for European sea bass providing a reliable tool to study gene expression patterns in this fish species. Results obtained by using this platform helped to increase our knowledge in the gene cascade of sex differentiation and give evidence of the complexity of the molecular processes. We described the gene expression profile of genes and pathways required to differentiate bipotential tissue to either an ovary or testis providing a deep transcriptomic analysis in the developing gonads. Resulting data may help to improve sex control in fish culture particularly in the European sea bass