G3BP1 G3BP

Ras GTPase-activating protein-binding protein 1 ;
G3BP-1 ;
EC 3.6.4.13 ;
ATP-dependent DNA helicase VIII ;
hDH VIII ;
GAP SH3 domain-binding protein 1 ;

G3BP stress granule assembly factor 1 (G3BP1) Homo sapiens This gene encodes one of the DNA-unwinding enzymes which prefers partially unwound 3'-tailed substrates and can also unwind partial RNA/DNA and RNA/RNA duplexes in an ATP-dependent fashion. This enzyme is a member of the heterogeneous nuclear RNA-binding proteins and is also an element of the Ras signal transduction pathway. It binds specifically to the Ras-GTPase-activating protein by associating with its SH3 domain. Several alternatively spliced transcript variants of this gene have been described , but the full-length nature of some of these variants has not been determined. [provided by RefSeq , Jul 2008] ,

cofactor:Magnesium. Required for helicase activity. ,Domain:The NTF2 domain mediates multimerization. ,Function:May be a regulated effector of stress granule assembly. Phosphorylation-dependent sequence-specific endoribonuclease in vitro. Cleaves exclusively between cytosine and adenine and cleaves MYC mRNA preferentially at the 3'-UTR. ATP- and magnesium-dependent helicase. Unwinds preferentially partial DNA and RNA duplexes having a 17 bp annealed portion and either a hanging 3' tail or hanging tails at both 5'- and 3'-ends. Unwinds DNA/DNA , RNA/DNA , and RNA/RNA substrates with comparable efficiency. Acts unidirectionally by moving in the 5' to 3' direction along the bound single-stranded DNA. ,PTM:Arg-435 is dimethylated , probably to asymmetric dimethylarginine. ,PTM:Phosphorylated exclusively on serine residues. Hyperphosphorylated in quiescent fibroblasts. Hypophosphorylation leads to a decrease in endoribonuclease activity (By similarity) . RASA1-dependent phosphorylation of Ser-149 induces a conformational change that prevents self-association. Dephosphorylation after HRAS activation is required for stress granule assembly. Ser-149 phosphorylation induces partial nuclear localization. ,similarity:Contains 1 NTF2 domain. ,similarity:Contains 1 RRM (RNA recognition motif) domain. ,subcellular location:Cytoplasmic in proliferating cells , can be recruited to the plasma membrane in exponentially growing cells (By similarity) . Cytosolic and partially nuclear in resting cells. Recruited to stress granules (SGs) upon either arsenite or high temperature treatment. Recruitment to SGs is influenced by HRAS. ,subunit:Binds to the SH3 domain of Ras GTPase-activating protein (RASA1) in proliferating cells. No interaction in quiescent cells Component of a TAU mRNP complex , at least composed of IGF2BP1 , ELAVL4 and G3BP (By similarity) . Interacts with USP10 , and may regulate it. Forms homodimers and oligomers. ,tissue specificity:Ubiquitous. ,

Cytoplasm , cytosol . Perikaryon . Cytoplasm , Stress granule . Nucleus . Cytoplasmic in proliferating cells (PubMed:11604510) . Cytosolic and partially nuclear in resting cells (PubMed:11604510) . Recruited to stress granules in response to arsenite treatment (PubMed:12642610 , PubMed:20180778) . The unphosphorylated form is recruited to stress granules (PubMed:12642610) . HRAS signaling contributes to this process by regulating G3BP dephosphorylation (PubMed:12642610) . .