Project description:Mosquito-borne flaviviruses maintain life cycles in mammals and mosquitoes. RNA interference (RNAi) has been demonstrated as an anti-flavivirus mechanism in mosquitoes; however, whether and how flavivirus induces and antagonizes RNAi-mediated antiviral immunity in mammals remains unknown. Here we showed that NS2A of Dengue virus-2 (DENV2) act as a viral suppressor of RNAi (VSR). When NS2A-mediated RNAi suppression was disabled, the resulting mutant DENV2 induced Dicer-dependent production of abundant DENV2-derived siRNAs in differentiated mammalian cells. Importantly, VSR-disabled DENV2 showed severe replication defects in mosquito and mammalian cells, and mice, which were rescued by the deficiency of RNAi. Moreover, NS2As of multiple flaviviruses act as VSRs in vitro and during viral infection in both organisms. Overall, our findings demonstrate that antiviral RNAi can be induced by flavivirus, while flavivirus uses NS2A as bona fide VSR to evade RNAi in mammals and mosquitoes, highlighting the importance of RNAi in flaviviral vector-host life cycles.
Project description:Whole body SIRT6 overexpression (SIRT6-tg) extends lifespan. Here we examine the effect of SIRT6 overexpression on liver mRNA profile
Project description:GPS2 binding sites in BMDMs can be localized specially in enhancers (H3K27ac) and promoters (H3K27ac, H3K4me3). Upon GPS2 knock-out in BMDMs, de-repression of certain inflammatory genes occur, as accompanied by increased recruitment of H3K27ac and H3K4me3 marks.
Project description:This experiement aims to know what the differences of protein translation are in the bone marrow derived macro-phages(BMDMs) from WT mice and Elp3 KO mice. We treated the BMDMs with or without IL-4 for 4 hours.
Project description:RECQL5 globally effects the distribution of RNA Polymerase II on genes in a dose dependent manner. Knock-down of RECQL5 reduces RNA Polymerase II density in the gene body, while increasing density on TSS and TTS. Overexpression shows exactly the opposite effect. We postulate that RECQL5 acts as a regulator of the elongation rate, more specifically, that the knock-down increases elongation rate while the overexpression decreases it. RNA Polymerase II ChIP-Seq upon knock-down of RECQL5 with either of two specific shRNAs or a CTRL shRNA, and upon Doxycycline induced overexpression of RECQL5 .
Project description:The Pim (proviral integration site for Moloney murine leukemia virus) proteins form a serine threonine kinase family that regulates cell proliferation, migration and cell survival. Here we demonstrate for the first time that a Pim1 kinase plays an essential role in antiviral innate immune responses. Specifically, our in vivo, in vitro and RNA-sequencing analyses showed that Pim1 was quickly upregulated after Toll-like receptor (TLR) stimulation in a NF-kB-dependent manner and then promoted IFN-b production by forming a cell-surface complex composed of TRIF-signaling molecules and IRF3 that promoted IRF3 phosphorylation, nuclear translocation, and IFN-b production. As shown by Pim1 knockdown and knockout, Pim1 was essential for this role but its kinase activity was not involved. Pim1-deficiency increased the susceptibility of mice to poly I:C-induced sepsis. Our study uncovers a previously unrecognized role for Pim1 in antiviral innate immune responses, thus providing a new target for controlling viral infection.
Project description:Objective- Vascular adventitia encompasses progenitors and is getting recognized as the major site of inflammation in early stage of atherosclerosis. However, the cellular atlas of the heterogeneous adventitial cells, the intercellular communication, the cellular response of adventitia to hyperlipidemia, and its contribution to atherosclerosis have been elusive. Approach and Results- Single-cell RNA sequencing was applied to wt (wild type) and ApoE (apolipoprotein E)-deficient aortic adventitia from 12-week-old C57BL/6J mice fed on normal laboratory diet with early stage of atherosclerosis. Unbiased clustering analysis revealed that the landscape of adventitial cells encompassed adventitial mesenchyme cells, immune cells (macrophages, T cells, and B cells), and some types of rare cells, for example, neuron, lymphatic endothelial cells, and innate lymphoid cells. Seurat clustering analysis singled out 6 nonimmune clusters with distinct transcriptomic profiles, in which there predominantly were stem/progenitor cell-like and proinflammatory population (Mesen II). In ApoE-deficient adventitia, resident macrophages were activated and related to increased myeloid cell infiltration in the adventitia. Cell communication analysis further elucidated enhanced interaction between a mesenchyme cluster and inflammatory macrophages in ApoE-deficient adventitia. In vitro transwell assay confirmed the proinflammatory role of SCA1+ (stem cell antigen 1 positive) Mesen II population with increased CCL2 (chemokine [C-C motif] ligand 2) secretion and thus increased capacity to attract immune cells in ApoE-deficient adventitia. Conclusions- Cell atlas defined by single-cell RNA sequencing depicted the heterogeneous cellular landscape of the adventitia and uncovered several types of cell populations. Furthermore, resident cell interaction with immune cells appears crucial at the early stage of atherosclerosis.
