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bioRxiv · 10.1101/2023.09.06.556571

Japanese Encephalitis Virus: A pan-proteome analysis for aggregation propensities and in vitro validation with Capsid anchor and 2K peptide

Abstract

Japanese encephalitis infection is a vector-borne disease caused by the flavivirus Japanese encephalitis virus (JEV). It is responsible of severe brain infection in humans worldwide. Given the ubiquitous nature of complications and tropism associated with Japanese encephalitis (JE) infection, a holistic understanding of its molecular mechanism is essential. The phenomenon of abnormal protein aggregation into pathogenic amyloids is now increasingly linked to multiple human diseases, also known as Amyloidosis. Most are neurodegenerative disorders but amyloidosis is not restricted to a specific organ or tissue type. The overlap of viral protein aggregation with human pathologies remains limited and it is gaining momentum, especially after the devastating Covid-19 pandemic. Therefore, in this study we have examined the likelihood of aggregation for the entire collection of proteins in JEV. Multiple independent web server tools were employed to scan for potential amyloid prone-regions (APRs), and it was followed by in vitro validation using two JEV transmembrane domains, Capsid anchor and 2K peptides. These synthetic viral peptides were introduced to artificial aggregation-inducing conditions and then analyzed using a different dye-based assays and microscopy methods confirming amyloid-like fibril structure formation. We found these aggregates cytotoxic to human neuronal cell line and membrane damaging to human blood derived RBCs. The aggregation kinetics of both peptides is enhanced in the presence of artificial membrane models and seeds of self and diabetes hallmark protein Amylin. Our findings thereby strongly suggest the possibility of JEV protein aggregation playing a vital role in its pathogenesis, opening up a broad scope of future study. Also, the interplay between JEV protein aggregation and initiation/progression of other proteopathies is possible and needs further exploration. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=116 SRC="FIGDIR/small/556571v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@2956d0org.highwire.dtl.DTLVardef@28128org.highwire.dtl.DTLVardef@6d7faaorg.highwire.dtl.DTLVardef@d89f40_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Saumya, K. U., Bharadwaj, T., Thakur, D. C., Verma, D., Giri, R.. 2023-09-07. Japanese Encephalitis Virus: A pan-proteome analysis for aggregation propensities and in vitro validation with Capsid anchor and 2K peptide. https://doi.org/10.1101/2023.09.06.556571

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