RNPS1

This gene encodes a protein that is part of a post-splicing multiprotein complex involved in both mRNA nuclear export and mRNA surveillance. mRNA surveillance detects exported mRNAs with truncated open reading frames and initiates nonsense-mediated mRNA decay (NMD). When translation ends upstream from the last exon-exon junction, this triggers NMD to degrade mRNAs containing premature stop codons. This protein binds to the mRNA and remains bound after nuclear export, acting as a nucleocytoplasmic shuttling protein. This protein contains many serine residues. Two splice variants have been found for this gene; both variants encode the same protein. [provided by RefSeq]

Full Name

RNA binding protein S1, serine-rich domain

Function

Part of pre- and post-splicing multiprotein mRNP complexes. Auxiliary component of the splicing-dependent multiprotein exon junction complex (EJC) deposited at splice junction on mRNAs. The EJC is a dynamic structure consisting of core proteins and several peripheral nuclear and cytoplasmic associated factors that join the complex only transiently either during EJC assembly or during subsequent mRNA metabolism. Component of the ASAP and PSAP complexes which bind RNA in a sequence-independent manner and are proposed to be recruited to the EJC prior to or during the splicing process and to regulate specific excision of introns in specific transcription subsets. The ASAP complex can inhibit RNA processing during in vitro splicing reactions. The ASAP complex promotes apoptosis and is disassembled after induction of apoptosis. Enhances the formation of the ATP-dependent A complex of the spliceosome. Involved in both constitutive splicing and, in association with SRP54 and TRA2B/SFRS10, in distinctive modulation of alternative splicing in a substrate-dependent manner. Involved in the splicing modulation of BCL2L1/Bcl-X (and probably other apoptotic genes); specifically inhibits formation of proapoptotic isoforms such as Bcl-X(S); the activity is different from the established EJC assembly and function. Participates in mRNA 3'-end cleavage. Involved in UPF2-dependent nonsense-mediated decay (NMD) of mRNAs containing premature stop codons. Also mediates increase of mRNA abundance and translational efficiency. Binds spliced mRNA 20-25 nt upstream of exon-exon junctions.

Biological Process

Biological Process mRNA splicing, via spliceosomeManual Assertion Based On ExperimentIBA:GO_Central
Biological Process negative regulation of mRNA splicing, via spliceosomeManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process nuclear-transcribed mRNA catabolic process, nonsense-mediated decayManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process positive regulation of apoptotic processManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process regulation of alternative mRNA splicing, via spliceosomeManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process RNA splicingManual Assertion Based On ExperimentTAS:ProtInc
Biological Process transcription, DNA-templatedManual Assertion Based On ExperimentTAS:ProtInc

Cellular Location

Nucleus
Nucleus speckle
Cytoplasm
Nucleocytoplasmic shuttling protein. Colocalizes with the core EJC, ALYREF/THOC4, NXF1 and UAP56 in the nucleus and nuclear speckles.

PTM

Phosphorylated on one or more of the four Ser/Thr residues (Ser-43, Thr-49, Ser-52 or Ser-53). Ser-53 phosphorylation site is important for splicing and translation stimulation activity in vitro.