Triple functional domain protein N-terminal GEF domain–Ras-related C3 botulinum toxin substrate 1 interaction (TrioN–Rac1)

The TrioN–Rac1 interaction involves the N-terminal guanine nucleotide exchange factor (GEF) domain of the Triple functional domain protein (Trio) and the small GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1). Trio is a large scaffolding protein that acts as a key regulator of the actin cytoskeleton by facilitating the transition of Rho GTPases from an inactive GDP-bound state to an active GTP-bound state (Schmidt & Debant, 2014, Endocrine Reviews). The N-terminal GEF domain, often referred to as TrioN or GEF1, specifically catalyzes the exchange of nucleotides on Rac1 and RhoG, playing a vital role in neuronal development, including neurite outgrowth and axon pathfinding (Bellanger et al., 2003, Journal of Cell Science). In a disease context, aberrant TrioN–Rac1 signaling is a major driver of metastasis in various cancers, such as uveal melanoma and breast cancer, where it promotes cell motility and invasion (Vaquero et al., 2017, Molecular Cancer Therapeutics). Furthermore, mutations in the Trio gene that affect its GEF1 activity are linked to neurodevelopmental disorders like autism and intellectual disability (Ba et al., 2016, American Journal of Human Genetics). Therapeutic strategies focus on small molecule inhibitors, such as ITX3, which selectively block the TrioN domain to prevent Rac1 activation without affecting other GEFs (Blangy et al., 2006, Journal of Biological Chemistry). Such inhibitors represent a promising approach for treating invasive cancers and certain neurological conditions by modulating actin-dependent cellular processes.

Other names

Trio GEF1–Rac1 interactionTrio-Rac1 signaling axisTrio-Rac1 complexTrio N-terminal GEF domain–Rac1 interaction

Inhibition of the guanine nucleotide exchange factor (GEF) activity of the Trio N-terminal domain (GEF1), which prevents the conversion of Rac1 from an inactive GDP-bound state to an active GTP-bound state.