SMG9, nonsense mediated mRNA decay factor(SMG9) Homo sapiens This gene encodes a regulatory subunit of the SMG1 complex, which plays a critical role in nonsense-mediated mRNA decay (NMD). Binding of the encoded protein to the SMG1 complex kinase scaffold protein results in the inhibition of its kinase activity. Mutations in this gene cause a multiple congenital anomaly syndrome in human patients, characterized by brain malformation, congenital heart disease and other features. [provided by RefSeq, Jul 2016],function:Component of the SMG1C complex, a mRNA surveillance complex that recognizes and degrades mRNAs containing premature translation termination codons (PTCs) via the nonsense-mediated mRNA decay (NMD). The complex probably acts by associating with ribosomes during tranlation termination on mRNPs. If an exon junction complex (EJC) is located 50-55 or more nucleotides downstream from the termination codon, smg1 phosphorylates upf1/rent1, triggering nonsense-mediated mRNA decay (NMD). In the SMG1C complex, it is required for the efficient association between smg1 and smg8.,PTM:Phosphorylated by SMG1.,similarity:Belongs to the SMG9 family.,subunit:Component of the SMG1C complex, at least composed of SMG1, SMG8 and SMG9. The SMG1C complex is then recruited on premature translation termination codons (PTCs) to form the ribosome:SURF complex, at least composed of ERF1, ERF3 (ERF3A or ERF3B), EEF2, UPF1/RENT1, SMG1, SMG8 and SMG9.,
