Project description:Bats are natural hosts for a wide diversity of viruses. While many of these viruses are highly pathogenic in humans, most do not appear to cause major symptoms in bats. These modern bat-specific characteristics are the result of past virus-host (co)evolution and virus-driven host adaptations. Innate immunity is the first line of defense against viruses in mammals, we aim at characterizing bat innate immunity in response to viruses. Using genome-wide and gene candidate evolutionary analyses, we found that many bat antiviral genes have undergone multiple duplication events in a lineage-specific manner, specifically in the Myotis bat lineage. We focus on Myotis yumanensis as a model in the Myotis lineage. We performed transcriptomic analyses and observed the upregulation of most mammalian genes implicated in the different steps of the innate immune response from sensing to interferon-stimulated genes (ISGs), showing the conservation of the core innate immunity. Our study will contribute to identifying adaptations that shaped bat innate immunity. These adaptations may contribute to the bat-virus specificity and influence viral emergence to another mammalian host
Project description:Bats are a major reservoir of zoonotic viruses, and there has been growing interest in characterizing bat-specific features of innate immunity and inflammation. Recent studies have revealed bat-specific adaptations affecting interferon (IFN) signaling and IFN-stimulated genes (ISGs), but we still have a limited understanding of the genetic mechanisms that have shaped the evolution of bat immunity. Here we investigated the transcriptional and epigenetic dynamics of transposable elements (TEs) during the type I IFN response in little brown bat (Myotis lucifugus) primary embryonic fibroblast cells, using RNA-seq and CUT&RUN. We found multiple bat-specific TEs that undergo both locus-specific and family-level transcriptional upregulation in response to IFN. Our transcriptome reassembly identified multiple ISGs that have acquired novel exons from bat-specific TEs, including NRLC5, SLNF5 and a previously unannotated isoform of the IFITM2 gene. We also identified examples of TE-derived regulatory elements, but did not find strong evidence supporting genome-wide epigenetic activation of TEs in response to IFN. Collectively, our study uncovers numerous TE-derived transcripts, proteins, and alternative isoforms that are induced by IFN in Myotis lucifugus cells, highlighting potential candidate loci that contribute to bat-specific immune function.
Project description:Bats are a major reservoir of zoonotic viruses, and there has been growing interest in characterizing bat-specific features of innate immunity and inflammation. Recent studies have revealed bat-specific adaptations affecting interferon (IFN) signaling and IFN-stimulated genes (ISGs), but we still have a limited understanding of the genetic mechanisms that have shaped the evolution of bat immunity. Here we investigated the transcriptional and epigenetic dynamics of transposable elements (TEs) during the type I IFN response in little brown bat (Myotis lucifugus) primary embryonic fibroblast cells, using RNA-seq and CUT&RUN. We found multiple bat-specific TEs that undergo both locus-specific and family-level transcriptional upregulation in response to IFN. Our transcriptome reassembly identified multiple ISGs that have acquired novel exons from bat-specific TEs, including NRLC5, SLNF5 and a previously unannotated isoform of the IFITM2 gene. We also identified examples of TE-derived regulatory elements, but did not find strong evidence supporting genome-wide epigenetic activation of TEs in response to IFN. Collectively, our study uncovers numerous TE-derived transcripts, proteins, and alternative isoforms that are induced by IFN in Myotis lucifugus cells, highlighting potential candidate loci that contribute to bat-specific immune function.
Project description:Microbial eukaryotes associated with the gut microbiome of the Valparaiso Myotis bat (Myotis arescens) in anthropized landscapes of central Chile.
