Agradecimentos: We acknowledge the students that helped ÉZ during the cell lines infection in the Biosafety Level 3 Laboratory (NB3) and all others that were our backup outside of the lab. We thank the UNICAMP-Task-Force against COVID-19 that facilitated this study. This work was supported by grants from FAEPEX-UNICAMP (2005/20; 2319/20; 2432/20; 2274/20; 2266/20), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), grant numbers 2020/05346-6, 2018/14818-9, 2020/04558-0 and 2016/00194-8. JP-M is supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) grant no number 305628/2020-8 Ver menos

Abstract: SARS-CoV-2 is an emerging virus from the Coronaviridae family and is responsible for the ongoing COVID-19 pandemic. In this work, we explored the previously reported SARS-CoV-2 structural membrane protein (M) interaction with human Proliferating Cell Nuclear Antigen (PCNA). The M protein is responsible for maintaining virion shape, and PCNA is a marker of DNA damage which is essential for DNA replication and repair. We validated the M-PCNA interaction through immunoprecipitation, immunofluorescence co-localization, and PLA (Proximity Ligation Assay). In cells infected with SARS-CoV-2 or transfected with M protein, using immunofluorescence and cell fractioning, we documented a reallocation of PCNA from the nucleus to the cytoplasm and the increase of PCNA and ?H2AX (another DNA damage marker) expression. We also observed an increase in PCNA and ?H2AX expression in the lung of a COVID-19 patient by immunohistochemistry. In addition, the inhibition of PCNA translocation by PCNA I1 and Verdinexor led to a reduction of plaque formation in an in vitro assay. We, therefore, propose that the transport of PCNA to the cytoplasm and its association with M could be a virus strategy to manipulate cell functions and may be considered a target for COVID-19 therapy Ver menos