Regulator of nonsense transcripts 3A (UniProt: Q9H1J1; also known as Nonsense mRNA reducing factor 3A, Up-frameshift suppressor 3 homolog A, hUpf3, UPF3A) is encoded by the UPF3A (also known as RENT3A, UPF3) gene (Gene ID: 65110) in human. UPF3A acts as an inhibitor of nonsense-mediated decay (NMD) of mRNAs containing premature stop codons by associating with the nuclear exon junction complex (EJC) and serving as link between the EJC core and NMD machinery. It is reported to shuttle between the nucleus and the cytoplasm. It recruits UPF2 at the cytoplasmic side of the nuclear envelope and the subsequent formation of an UPF1-UPF2-UPF3 surveillance complex is believed to activate NMD. However, UPF3A is shown to be only marginally active in NMD as compared to UPF3B. It binds spliced mRNA upstream of exon-exon junctions. Mice lacking UPF3A exhibit hyper NMD and show defects in embryogenesis and gametogenesis. In human three isoforms of UPF3A have been described that are produced by alternative splicing. (Ref.: Shum, EY., et al. (2016). Cell. 165(2); 382-395).，官网链接：https://www.sigmaaldrich.cn/product/mm/abe1878 默克 科研、开发、生产。 作为生命科学行业的全球领先供应商，我们致力于为科研、生物技术开发和生产，以及制药药物疗法开发和生产提供各类解决方案和服务。

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