A CONCISE IN SILICO PREDICTION REPORT OF A POTENTIAL PRION-LIKE DOMAIN IN SARS-COV-2 POLYPROTEIN

Abstract

COVID-19 has shown higher virulence compared to the previous coronavirus epidemics and has shown that it causes damages to the nervous system. In the present study, PrionW web server was used to predict the prion-like domains (PrLDs) in 15 structural and non-structural proteins of SARS-CoV, MERS-CoV and SARS-CoV-2. Among all of these proteins, the results demonstrated one PrLD with the sequence 951EDDYQGKPLEFGATSAALQPEEEQEEDWLDDDSQQTVGQQDGSEDNQTTTIQTIVEVQPQL1012, having an amyloid-core of 988GQQDGSEDNQTTTIQTIVEVQ1009 in the non-structural protein of SARS-CoV-2 with pWALTZ_Score of 59.9936. The sequence of SARS-CoV-2 polyprotein was further investigated by FoldIndex© tool, and a negative fold index was demonstrated at the site of predicted prion-like domain. Multiple sequence alignment of this region with non-structural proteins of SARS-CoV and MERS-CoV, showed that there is no sequence similarity between this predicted region and the corresponding regions of two other viruses. Considering the high similarity between polyproteins of SARS-CoV-2 and SARS-CoV, and their ability to affect the nervous system, it could be suggested that a potential PrLD might be added to SARS-CoV polyprotein.