The NSP1 is critical in regulating viral translation or replication. It Inhibits host gene expression by interacting with the 40S ribosomal subunit, a key component of the cellular translation machinery, and blocking the ribosomal entry site to prevent host mRNA binding. The NSP1-40S ribosome complex further induces an endonucleolytic RNA cleavage near the 5'UTR of cellular host mRNAs, targeting them for degradation. Viral mRNAs are not susceptible to NSP1-mediated endonucleolytic RNA cleavage owing to the presence of a 5'-end leader sequence and are therefore protected from degradation. By inducing suppression of host translation, NSP1 facilitates efficient viral gene expression in infected cells and evasion from host immune response

MESLVPGFNEKTHVQLSLPVLQVRDVLVRGFGDSVEEVLSEARQHLKDGTCGLVEVEKGVLPQLEQPYVFIKRSDARTAPHGHVMVELVAELEGIQYGRSGETLGVLVPHVGEIPVAYRKVLLRKNGNKGAGGHSYGADLKSFDLGDELGTDPYEDFQENWNTKHSSGVTRELMRELNGG

180 aa; 150 kDa