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Woosley, H.

Publications and source records attributed to Woosley, H..

3 recordsLinked to original sources

V-SWITCH: A single-vector OFF-to-ON fluorescent reporter of live RNA virus infections

Fluorescent reporters of viral infection are powerful tools for studying viral pathogenesis and host-pathogen interactions. Here, we present V-SWITCH, a highly modular, single-vector, cell-based OFF-to-ON fluorescent reporter that enables robust detection of viral infection in living cells. V-SWITCH is based on a split mNeonGreen (mNG) system employing a release-and-capture mechanism. In the "OFF" state, the mNG3A(1-10) fragment is anchored to the endoplasmic reticulum via a Sec61 transmembrane domain, while the mNG(11) fragment, fused to BFP, is constitutively expressed in the nucleus. Upon infection, the viral protease cleaves a protease cleavage site (PCS) adjacent to the mNG3A(1-10) fragment, liberating it for translocation into the nucleus. There, it complements mNG(11) to reconstitute fluorescence. The constitutive BFP serves as both an expression control and a nuclear segmentation marker for image analysis. Each module in this dual-cassette design is flanked by unique restriction sites allowing rapid swapping of virus-specific PCS, split fluorophores, membrane anchors, and promoters. We demonstrate the versatility of the V-SWITCH reporter for several viruses (Dengue virus, Zika virus, West Nile virus and Human Coronavirus OC43) in several cell lines (A549, BJ-5 fibroblasts, HEK293T and HeLa). Reporter activation enables clear discrimination of infected and uninfected cells by flow cytometry and reveals time-dependent and heterogeneous infection dynamics by live-cell imaging at single-cell resolution. Importantly, we demonstrate the potential of V-SWITCH to support both rapid functional screening for host factor dependencies, as well as high-throughput compound screening to enable antiviral discovery and comparative evaluation of therapeutic strategies across multiple viruses and cell types.

microbiology↗

Spatio-temporal analysis of Vaccinia virus infection and host response dynamics using single-cell transcriptomics and proteomics

Poxviruses are a large group of DNA viruses with exclusively cytoplasmic life cycles and complex gene expression programs. A number of systems-level studies have analyzed bulk transcriptome and proteome changes upon poxvirus infection, but the cell-to-cell heterogeneity of the transcriptomic response, and the subcellular resolution of proteomic changes have remained unexplored. Here, we measured single-cell transcriptomes of Vaccinia virus-infected populations of HeLa cells and immortalized human fibroblasts, resolving the cell-to-cell heterogeneity of infection dynamics and host responses within those cell populations. We further integrated our transcriptomic data with changes in the levels and subcellular localization of the host and viral proteome throughout the course of Vaccinia virus infection. Our findings from single-cell RNA sequencing indicate conserved transcriptome changes independent of the cellular context, including widespread host shutoff, heightened expression of cellular transcripts implicated in stress responses, the rapid accumulation of viral transcripts, and the robust activation of antiviral pathways in bystander cells. While most host factors were co-regulated at the RNA and protein level, we identified a subset of factors where transcript and protein levels were discordant in infected cells; predominantly factors involved in transcriptional and post-transcriptional mRNA regulation. In addition, we detected the relocalization of several host proteins such as TENT4A, NLRC5, and TRIM5, to different cellular compartments in infected cells. Collectively, our comprehensive data provide spatial and temporal resolution of the cellular and viral transcriptomes and proteomes and offer a robust foundation for in-depth exploration of virus-host interactions in poxvirus-infected cells.

microbiology↗

BiP/GRP78 is a pro-viral factor for diverse dsDNA viruses that promotes the survival and proliferation of cells upon KSHV infection

The Endoplasmic Reticulum (ER)-resident HSP70 chaperone BiP (HSPA5) plays a crucial role in maintaining and restoring protein folding homeostasis in the ER. BiPs function is often dysregulated in cancer and virus-infected cells, conferring pro-oncogenic and pro-viral advantages. We explored BiPs functions during infection by the Kaposis sarcoma-associated herpesvirus (KSHV), an oncogenic gamma-herpesvirus associated with cancers of immunocompromised patients. Our findings reveal that BiP protein levels are upregulated in infected epithelial cells during the lytic phase of KSHV infection. This upregulation occurs independently of the unfolded protein response (UPR), a major signaling pathway that regulates BiP availability. Genetic and pharmacological inhibition of BiP halts KSHV viral replication and reduces the proliferation and survival of KSHV-infected cells. Notably, inhibition of BiP limits the spread of other alpha- and beta-herpesviruses and poxviruses with minimal toxicity for normal cells. Our work suggests that BiP is a potential target for developing broad-spectrum antiviral therapies against double-stranded DNA viruses and a promising candidate for therapeutic intervention in KSHV-related malignancies.

microbiology↗