protein kinase C conserved region 1 (C1 domain) found in the 190 kDa guanine nucleotide exchange factor (p190RhoGEF)-like family
The p190RhoGEF-like protein family includes p190RhoGEF, Rho guanine nucleotide exchange factor 2 (ARHGEF2), A-kinase anchor protein 13 (AKAP-13) and similar proteins. p190RhoGEF is a brain-enriched, RhoA-specific guanine nucleotide exchange factor that regulates signaling pathways downstream of integrins and growth factor receptors. It is involved in axonal branching, synapse formation and dendritic morphogenesis, as well as in focal adhesion formation, cell motility and B-lymphocytes activation. ARHGEF2 acts as a 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. AKAP-13 is a scaffold protein that plays an important role in assembling signaling complexes downstream of several types of G protein-coupled receptors. It activates RhoA in response to signaling via G protein-coupled receptors via its function as Rho guanine nucleotide exchange factor. It may also activate other Rho family members. AKAP-13 plays a role in cell growth, cell development and actin fiber formation. Members of this family share a common domain architecture containing C1, RhoGEF or Dbl-homologous (DH), and Pleckstrin Homology (PH) domains. Some members may contain additional domains such as the DUF5401 domain. This model describes 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.