protein kinase C conserved region 1 (C1 domain) found in Rho guanine nucleotide exchange factor 2 (ARHGEF2) and similar proteins
ARHGEF2, also called guanine nucleotide exchange factor H1 (GEF-H1), microtubule-regulated Rho-GEF, or proliferating cell nucleolar antigen p40, acts as guanine nucleotide exchange factor (GEF) that activates Rho-GTPases by promoting the exchange of GDP for GTP. It is thought to play a role in actin cytoskeleton reorganization in different tissues since its activation induces formation of actin stress fibers. ARHGEF2 may be involved in epithelial barrier permeability, cell motility and polarization, dendritic spine morphology, antigen presentation, leukemic cell differentiation, cell cycle regulation, innate immune response, and cancer. It contains a C1 domain followed by Dbl-homology (DH) and pleckstrin-homology (PH) domains which bind and catalyze the exchange of GDP for GTP on RhoA. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.