Inhibition of glycogen synthase kinase-3-beta (GSK3β) blocks nucleocapsid phosphorylation and SARS-CoV-2 replication

Abstract

GSK3β has been proposed to have an essential role in Coronaviridae infection. Screening of a targeted library of GSK3β inhibitors against SARS-CoV-2 and HCoV-229E resulted in identification of high proportion of active compounds with low toxicity to host cells. A select lead compound, T-1686568, showed dose-dependent activity against SARS-CoV-2 transcription, translation and viral particle release in multiple cell lines and primary organoids. A protein kinase substrate profiling assay combined with western blot analysis showed that SARS-CoV-2 nucleocapsid is phosphorylated by GSK3β on S180/S184, S190/S194 and T198 which have already been primed in the adjacent phospho-sites S188, T198 and S206 respectively. Inhibition by T-1686568 resulted in reduction of the S1 Spike protein levels, an accumulation of the Nucleocapsid (N) protein and maintenance of the non-structural (NSP2) level in infected Huh-7.5.1 cells, indicating that N phosphorylation might serve as a critical precursor for processing and release of mature viruses.

Melatonin: Regulation of Viral Phase Separation and Epitranscriptomics in Post-Acute Sequelae of COVID-19

“…A meta-analysis of clinical data from more than 300,000 COVID-19 patients in three major health systems using a random-effects model revealed a 50% reduction in risks in patients who take lithium which is a direct inhibitor of GSK-3, while in vitro results showed that GSK-3 inhibition effectively impaired viral replication and blocked infection in human lung epithelial cells [ 569 ]. Selective screening of a library of GSK-3β inhibitors found a high proportion of compounds that inhibited GSK-3β were also effective in reducing SARS-CoV-2 infection [ 570 ].…”