G-rich RNA sequence binding factor 1 (GRSF1)

G-rich RNA sequence binding factor 1 (GRSF1) is an RNA-binding protein and member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family, encoded by nuclear DNA but localizing to mitochondria. It regulates post-transcriptional processing of mitochondrial RNAs, is required for the assembly of mitochondrial ribosomes, and is critical for recruitment of mRNAs and lncRNAs for efficient mitochondrial translation and oxidative phosphorylation. Loss or depletion of GRSF1 impairs mitochondrial function, elevates reactive oxygen species, disrupts redox homeostasis and NAD+/NADH balance, induces DNA damage, and activates cellular senescence pathways including mTOR and NF-κB, increasing inflammatory cytokines (notably IL6). In tumors such as colorectal cancer, GRSF1 acts as a suppressor of proliferation and metastasis, in part by restraining Ras/PI3K/AKT pathway activation and inflammatory programs. Reduced GRSF1 expression is associated with poor prognosis in colorectal cancer, and the protein is under investigation as a potential tumor suppressor and therapeutic target in oncology and age-related disease biology.

Other names

G-rich RNA sequence-binding factor 1G-rich sequence factor 1GRSF-1GRSF1

No direct small molecule or pharmaceutical modulators are described in current literature. Loss of function or reduced expression leads to dysregulation of mitochondrial function, increased ROS, DNA damage, activation of mTOR and NF-κB signaling pathways (implicating potential indirect interaction with pathway-targeting drugs).