G3BP2

G3BP2, or Ras GTPase-activating protein-binding protein 2, is a human RNA-binding protein that functions as a paralog of G3BP1. It is involved in the regulation of RNA metabolism and the cellular response to stress, notably contributing to the formation of cytoplasmic stress granules during environmental challenges.

The protein architecture of G3BP2 includes an N-terminal NTF2-like domain, which mediates dimerization and interactions with other proteins, and a C-terminal region containing an RNA recognition motif (RRM) along with acidic and proline-rich segments. This domain organization supports both protein–protein interactions and RNA binding. Alternative splicing produces multiple G3BP2 isoforms that differ in their N- and/or C-terminal regions, which can influence localization and function.

In response to cellular stress such as oxidative or heat stress, G3BP2 localizes to stress granules and acts as a nucleating factor that helps recruit other granule components and mRNAs. Through its RNA-binding capacity, it modulates the stability and translation of target transcripts during stress, contributing to rapid post-transcriptional regulation. G3BP2 participates in signaling pathways related to cell growth and antiviral responses and can influence p53 signaling in certain cellular contexts through its interactions within stress granule–associated networks.

Regulation of G3BP2 expression and activity is influenced by cellular stress cues and post-translational modifications. Aberrant expression or function of G3BP2 has been observed in various cancers and during viral infections, suggesting potential roles in disease mechanisms and as a biomarker or therapeutic target. Research on G3BP2 often focuses on its role in stress granule dynamics and its impact on RNA metabolism under stress conditions.