Project description:description Blastocystis sp. is a highly prevalent anaerobic eukaryotic parasite of humans and animals. The genome of several representatives has been sequenced revealing specific traits such as an intriguing 3’-end processing of primary transcripts. We have acquired a first high-throughput proteomics dataset on the difficult to cultivate ST4 isolate WR1 and detected 2,761 proteins. We evidenced for the first time by proteogenomics a functional termination codon derived from transcript polyadenylation for seven different key cellular components.
Project description:Coronaviruses express a repertoire of accessory proteins for evading host immune responses. A small internal (I) accessory gene overlaps with the nucleocapsid (N) gene in an alternative reading frame of viruses that belong to the genus Betacoronavirus. Previous studies reported that I proteins of SARS-CoV (9b), MERS-CoV (8b) and SARS-CoV-2 (9b) inhibit type I interferon (IFN-I) expression through distinct mechanisms and have different roles in pathogenesis. In contrast, the functions of the I proteins of human coronaviruses HCoV-HKU1 (7b) and HCoV-OC43 (8b) have not been previously reported. Although HCoV-HKU1 and HCoV-OC43 predominantly cause common cold in healthy adults (common cold CoVs, CCCoVs), susceptible individuals infected with these viruses can develop severe disease. The lack of robust reverse genetic systems, tissue culture and animal models limit the study of HCoV-HKU1 and HCoV-OC43 pathogenesis. Here, we examined how the heterologous expression of the HCoV-HKU1 and HCoV-OC43 I proteins impact pathogenesis in a mouse model of infection using a prototypic betacoronavirus. We inserted the I gene of HCoV-HKU1 (ORF 7b) and HCoV-OC43 (ORF 8b) independently into the genome of a neurotropic strain of mouse hepatitis virus (J2.2). J2.2 infection is well characterized with clearly defined immune responses which allows the study of these genes in the context of authentic coronavirus infection. We showed that ORF 7b of HCoV-HKU1, but not ORF 8b of HCoV-OC43, ameliorated MHV-J2.2 pathogenesis while ORF 8b of MERS-CoV exacerbated disease. The presence of HCoV-HKU1 ORF 7b decreased virus titers and cytokine expression while ORF 8b of MERS-CoV led to increased immune cell infiltration and virus titers in mice after J2.2 infection. Moreover, proteins expressed by ORF 7b of HCoV-HKU1 and ORF 8b of HCoV-OC43 showed different patterns of subcellular localization. Overall, our findings suggest that the I genes of different betacoronaviruses play unique roles in pathogenesis.
Project description:In rainbow trout, type A spermatogonia can be split into SP cells and non-SP cells by the ability to exclude Hoechst 33342 dye (H33342). The H33342 fluorescence of SP cells are lower than that of non-SP cells, after H33342 staining. To investigate whether SP cells were transcriptomically distinct from non-SP cells, we compared the transcriptome of these cells. We used fluorescence-activated cell sorting (FACS) to isolate SP cells and non-SP cells from the type A spermatogonia in rainbow trout.