UPF1 Rabbit Polyclonal Antibody

UPF1 (up-frameshift mutant 1) is an RNA helicase and a phosphorylation-regulated RNA-binding protein that serves as the core factor of the nonsense-mediated mRNA decay (NMD) pathway, playing a critical role in RNA quality surveillance in eukaryotes. UPF1 is the catalytic core of the SURF complex (comprising UPF1, UPF2, UPF3B, SMG1, etc.), and through coordination with the translation termination complex and the exon junction complex, it recognizes and degrades aberrant transcripts containing premature termination codons, thereby preventing the production of truncated proteins and their potential dominant-negative effects. The function of UPF1 is dynamically regulated by its phosphorylation status: SMG1 kinase phosphorylates UPF1 at multiple serine/threonine residues (e.g., within the Ser/Thr-rich region) to activate its helicase activity, while phosphatases such as SMG5, SMG6, and SMG7 are responsible for its dephosphorylation cycle—this phosphorylation-dephosphorylation rhythm is essential for the precise operation of the NMD pathway. Beyond its classical NMD function, UPF1 is also widely involved in various biological processes including mRNA degradation (such as Staufen-mediated decay), transcriptional regulation, DNA replication, and telomere maintenance, regulating gene expression through direct RNA binding or interactions with other proteins. Mutations or aberrant expression of UPF1 are closely associated with human genetic diseases (such as UPF1-related autosomal dominant intellectual disability), cancer development and progression, and viral infections (many viruses evade NMD surveillance by targeting and suppressing UPF1), making UPF1 an important target in RNA metabolism and disease research.