Project description:Pubertal development in males starts with the onset of spermatogenesis that implies the division of primary spermatogonia and their subsequent entry into meiosis. Whole genome microarray expression profile was used as a means to explore the molecular basis underlying the onset of pubertal development in sea bass. The present study is aimed at the characterization of the expression of genes involved in the onset of spermatogenesis in the European sea bass. The study is focused on the first stages of the process including the appearance of spermatocytes and thus the first meiotic divisions. The transcriptomic study using a sea bass-specific microarray resulted in a number of genes differentially expressed during the onset of spermatogenesis. Among those, genes involved in cell-cycle progression, microtubule assembly during meiosis or retinoic acid signaling pathway indicating that they can be used as potential molecular markers for the onset of spermatogenesis in sea bass.
Project description:IL10-/-DC pulsed for 6h with 0, SEA, LPS, or co-pulsed with SEA/LPS together to compare changes in LPS-induced gene expression mediated by SEA (Schistosome soluble egg antigen) Keywords: other
Project description:Sea urchins are emblematic marine animals with a rich fossil record and represent instrumental models for developmental biology. As echinoderms, sea urchins display several characteristics that set them apart from other deuterostomes such as their highly regulative embryonic development and their unique pentaradial adult body plan. To determine whether these characteristics are linked to particular genomic rearrangement or gene regulatory rewiring, we introduce a chromosome-scale genome assembly for sea urchin Paracentrotus lividus as well as extensive transcriptomic and epigenetic profiling during its embryonic development. We found that sea urchins show opposite modalities of genome evolution as compared to those of vertebrates: they retained ancestral chromosomal linkages that otherwise underwent mixing in vertebrates, while their intrachromosomal gene order has evolved much faster between sea urchin species that split 60 Myr ago than it did in vertebrates. We further assessed the conservation of the cis-regulatory program between sea urchins and chordates and identified conserved modules despite the developmental and body plan differences. We documented regulatory events underlying processes like zygotic genome activation and transition to larval stage in sea urchins. We also identified a burst of gene duplication in the echinoid lineage and showed that some of these expanded genes are involved in organismal novelties, such as Aristotle's lantern, tube feet, or in the specification of lineages through for instance the pmar1 and pop genes. Altogether, our results suggest that gene regulatory networks controlling development can be conserved despite extensive gene order rearrangement.
Project description:The human facilitates chromatin transcription (FACT) complex is a chromatin remodeller composed of human suppressor of Ty 16 homologue (hSpt16) and structure-specific recognition protein-1 subunits that regulates cellular gene expression. Whether FACT regulates host responses to infection remained unclear. We identify a FACT-mediated, interferon-independent, antiviral pathway that restricts poxvirus replication. Cell culture and bioinformatics approaches suggest that early viral gene expression triggers nuclear accumulation of SUMOylated hSpt16 subunits required for the expression of E26 transformation-specific sequence-1 (ETS-1)-a transcription factor that activates virus restriction programs. However, biochemical studies show that poxvirus-encoded A51R proteins block ETS-1 expression by outcompeting structure-specific recognition protein-1 binding to SUMOylated hSpt16 and by tethering SUMOylated hSpt16 to microtubules. Furthermore, A51R antagonism of FACT enhances poxvirus replication in human cells and virulence in mice. Finally, we show that FACT also restricts rhabdoviruses, flaviviruses and orthomyxoviruses, suggesting broad roles for FACT in antiviral immunity. Our study reveals the FACT-ETS-1 antiviral response (FEAR) pathway to be critical for eukaryotic antiviral immunity and describes a unique mechanism of viral immune evasion.
Project description:We identified cis-regulatory elements based on their dynamic chromatin accessibility during the gastrula-larva stages of sea urchin and sea star and studied their evolution in these echinoderm species
Project description:This study observes the origin of the last living sea nomad group in Indonesia using genome-wide SNP data, and tracks their dispersal in the archipelago. This study involves new samples on not only the sea nomad group, but also surrounding populations where the sea nomad settled. We revealed the scenario of their origin and unique admixture patterns during their dispersal and re-settlement.