Ras GTPase-activating protein-binding protein 1; G3BP-1; ATP-dependent DNA helicase VIII; hDH VIII; GAP SH3 domain-binding protein 1 (G3BP1 G3BP)

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Function

may be a regulated effector of stress granule assembly
phosphorylation-dependent sequence-specific endoribonuclease in vitro
cleaves exclusively between cytosine & adenine & cleaves MYC mRNA preferentially at the 3'-UTR
ATP- & Mg+2-dependent helicase
unwinds preferentially partial DNA & RNA duplexes having a 17 bp annealed portion & either a hanging 3' tail or hanging tails at both 5'- & 3'-ends
unwinds DNA/DNA, RNA/DNA, & RNA/RNA substrates with comparable efficiency
acts unidirectionally by moving in the 5' to 3' direction along the bound single-stranded DNA
phosphorylated exclusively on Ser
hyperphosphorylated in quiescent fibroblasts
hypophosphorylation leads to a decrease in endoribonuclease activity (putative)
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
Arg-435 is dimethylated, probably to asymmetric dimethylarginine
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 & G3BP (putative)
interacts with USP10, & may regulate it
forms homodimers & oligomers

Cofactor: Mg+2; required for helicase activity

cytoplasm, cell membrane. nucleus
cytoplasmic in proliferating cells
can be recruited to the plasma membrane in exponentially growing cells (putative)
cytoplasm & partially nuclear in resting cells
recruited to stress granules upon treatment with either arsenite or high temperature
- recruitment to stress granules is influenced by HRAS