G3BP1
Description
The G3BP1 (G3BP stress granule assembly factor 1) is a protein-coding gene located on chromosome 5.
Ras GTPase-activating protein-binding protein 1 is an enzyme that in humans is encoded by the G3BP1 gene. 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 was originally reported to bind specifically to the Ras-GTPase-activating protein by associating with its SH3 domain, but this interaction has recently been challenged. 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. G3BP1 can initiate stress granule formation and labeled G3BP1 is commonly used as a marker for stress granules.
== Interactions == G3BP1 has been shown to interact with USP10. It also interacts with SND1[5].
== References ==
[5]Gao X, Ge L, Shao J, Su C, Zhao H, Saarikettu J, Yao X, Yao Z, Silvennoinen O, Yang J., Tudor-SN interacts with and co-localizes with G3BP in stress granules under stress conditions.FEBS Letters, Volume 584, Issue 16, Pages 3525-3532.
== Further reading ==
== External links == G3BP1 human gene location in the UCSC Genome Browser.
G3BP1 is a protein involved in various cellular processes, including stress granule formation and innate immunity. It plays a crucial role in the formation of stress granules, which are membraneless compartments that store mRNAs and proteins in response to cellular stress. G3BP1 promotes stress granule formation by undergoing liquid-liquid phase separation (LLPS) upon binding to unfolded RNA, acting as a molecular switch that triggers LLPS in response to increased intracellular free RNA concentrations. G3BP1 also functions as an ATP- and magnesium-dependent helicase, unwinding DNA/DNA, RNA/DNA, and RNA/RNA substrates with comparable efficiency. It acts unidirectionally, moving in the 5' to 3' direction along the bound single-stranded DNA. G3BP1 preferentially unwinds partial DNA and RNA duplexes with a 17 bp annealed portion and either a hanging 3' tail or hanging tails at both 5'- and 3'-ends. G3BP1 plays a vital role in innate immunity by promoting the activity of the proteins cGAS and RIGI. It participates in the DNA-triggered cGAS/STING pathway by promoting the DNA binding and activation of cGAS, triggering its condensation, potentially linked to the formation of membrane-less organelles. G3BP1 also enhances RIGI-induced type I interferon production, likely by assisting RIGI in sensing pathogenic RNA. Additionally, G3BP1 may act as a phosphorylation-dependent sequence-specific endoribonuclease in vitro, cleaving exclusively between cytosine and adenine and preferentially cleaving MYC mRNA at the 3'-UTR.
G3BP1 is also known as G3BP, HDH-VIII.
