RAPGEF4
Description
The RAPGEF4 (Rap guanine nucleotide exchange factor 4) is a protein-coding gene located on chromosome 2.
RAPGEF4, also known as Epac2, is a protein encoded by the RAPGEF4 gene in humans. It serves as a target for cAMP, a crucial secondary messenger within various cells. Primarily expressed in brain, neuroendocrine, and endocrine tissues, Epac2 functions as a guanine nucleotide exchange factor for the Ras-like small GTPase Rap when stimulated by cAMP. It participates in a variety of cellular processes mediated by cAMP in endocrine and neuroendocrine cells, as well as neurons. RAPGEF4 is located on chromosome 2q31-q32 and generates three isoforms (Epac2A, Epac2B, and Epac2C) through alternative promoter usage and differential splicing. The most common isoform, Epac2A, is a multi-domain protein with 1,011 amino acids, primarily found in brain, neuroendocrine, and endocrine tissues such as pancreatic islets and neuroendocrine cells. It consists of two regions: an amino-terminal regulatory region and a carboxy-terminal catalytic region. The regulatory region contains two cyclic nucleotide-binding domains (cNBD-A and cNBD-B) and a DEP (Dishevelled, Egl-10, and Pleckstrin) domain. The catalytic region, responsible for activating Rap, comprises a CDC25 homology domain (CDC25-HD), a Ras exchange motif (REM) domain, and a Ras association (RA) domain.
RAPGEF4 is also known as CAMP-GEFII, CGEF2, EPAC, EPAC 2, EPAC2, Nbla00496.
Associated Diseases
- schizophrenia
- substance abuse
- Brugada syndrome
- alpha thalassemia-intellectual disability syndrome type 1
- beta-thalassemia-X-linked thrombocytopenia syndrome
