nsp1 Products

Description

Non-structural protein 1 (NSP1) is one of several functional proteins released by ORF1a-encoded protease cleavage of the pp1a and pp1ab replicase polyproteins expressed from the coronavirus (CoV) genome (1). The NSPs are involved in the replication and transcription of the viral RNA and not incorporated within the virion particles. Coronaviruses include various highly pathogenic strains such as SARS-CoV, MERS-CoV and SARS-CoV2 that have had significant impact on humans as well as strains that have negatively impacted livestock. NSP1, also known as the host shutoff factor, is a small 180 amino acid highly conserved protein among the first to be expressed following cell entry.  It is composed of an N-terminal domain, a linker region, and a C-terminal domain with a conserved KH motif that is required and sufficient for specific contacts with ribosomes (2, 3). The C-terminal domain binds tightly to and sterically occludes the entrance region of the mRNA channel in free 40S subunits, 43S pre-initiation complex, and empty, non-translating 80S ribosomes (2, 3) to inhibit translation. NSP1 blocks the innate immune response through suppression of host gene expression. By preventing translation of interferon and downstream signaling responses, it plays a key role in immune evasion (2, 4, 5). NSP1 also induces endonucleolytic cleavage of host mRNAs (6,7). Concomitant translation of more efficiently recognized untranslated regions (UTR) of viral mRNA along with resistance to endonucleolytic cleavage (7) is thought to lead to a switch to production of viral mRNA over host cell mRNA during an infection (3,8). Given the critical role NSP1 plays in virulence, it is an attractive target for small-molecule inhibition and vaccination development (9, 10).  

Bioinformatics

Uniprot	YP_009725297.1
Alternate Names	NSP1