ARHGEF40

Acts as a guanine nucleotide exchange factor (GEF) for RHOA and RHOC. Promotes actin stress fiber formation, force-induced stress fiber reinforcement and organization of KRT8/KRT18 networks via activation of RHOA/ROCK signaling, which is mediated by N-terminus KRT18 binding. Regulates the formation or maintenance of properly elongated morphology of epithelial tubules, via mediation of the organization and orientation of KRT18 filaments (By similarity). Promotes RHOA-dependent, cell-cell contact mediated reorientation of endothelial cells and their actin stress fibers in response to mechanotransduction. Positively regulates hemidesmosome formation via acting as a linker protein that anchors keratin filaments to hemidesmosomes. Also required for JUP localization at cell-cell adhesion junctions..

Function from UniProtKB (Q8TER5), read 2026-09-23. CC BY 4.0.