Non structural Protein 15

Non-structural protein 15 (NSP15) is a uridine-specific endoribonuclease (NendoU) encoded by the SARS-CoV-2 genome. It is a 334-amino acid protein with a molecular weight of approximately 38.02 kDa. NSP15 is processed from the viral polyprotein 1ab and plays a role in viral RNA processing and immune evasion by cleaving viral RNA at uridylate residues. The protein forms a hexamer in its active state and exhibits manganese-dependent endoribonuclease activity. In this study, recombinant NSP15 was expressed in E. coli, purified, and analyzed in solution using small-angle X-ray scattering (SAXS) to investigate its low-resolution structure and oligomeric state under near-physiological conditions.