hnRNP Q, Glycine- and tyrosine-rich RNA-binding protein, GRY-RBP, NS1-associated protein 1, Synaptotagmin-binding, cytoplasmic RNA-interacting protein | HNRPQ, NSAP1
Primary ID
O60506
Links
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Type
protein
Relations
1
Function
Heterogenous nuclear ribonucleoprotein (hnRNP) implicated in mRNA processing mechanisms. Component of the CRD-mediated complex that promotes MYC mRNA stability. Isoform 1, isoform 2 and isoform 3 are associated in vitro with pre-mRNA, splicing intermediates and mature mRNA protein complexes. Isoform 1 binds to apoB mRNA AU-rich sequences. Isoform 1 is part of the APOB mRNA editosome complex and may modulate the postranscriptional C to U RNA-editing of the APOB mRNA through either by binding to A1CF (APOBEC1 complementation factor), to APOBEC1 or to RNA itself. May be involved in translationally coupled mRNA turnover. Implicated with other RNA-binding proteins in the cytoplasmic deadenylation/translational and decay interplay of the FOS mRNA mediated by the major coding-region determinant of instability (mCRD) domain. Interacts in vitro preferentially with poly(A) and poly(U) RNA sequences. Isoform 3 may be involved in cytoplasmic vesicle-based mRNA transport through interaction with synaptotagmins. Component of the GAIT (gamma interferon-activated inhibitor of translation) complex which mediates interferon-gamma-induced transcript-selective translation inhibition in inflammation processes. Upon interferon-gamma activation assembles into the GAIT complex which binds to stem loop-containing GAIT elements in the 3'-UTR of diverse inflammatory mRNAs (such as ceruplasmin) and suppresses their translation; seems not to be essential for GAIT complex function.
Novel in vivo tyrosine phosphorylation sites were found in the fgfr-1, phospholipase cgamma, p90 ribosomal s6 kinase, cortactin, and ns-1-associated protein-1. Syncrip, was very recently found to be phosphorylated in response to insulin treatment of 3t3-l1 adipocytes (32). Phosphorylation of syncrip was accommodated by the insulin receptor tyrosine kinase in vitro but was inhibited upon binding of rna. Tyrosine phosphorylation at tyr-373 in the third rna recognition motif domain of nsap1/syncrip can possibly influence its rna binding properties and thus link fgfr-1 signaling to mrna metabolism.