RASGRP1
Description
The RASGRP1 (RAS guanyl releasing protein 1) is a protein-coding gene located on chromosome 15.
RASGRP1, encoded by the RASGRP1 gene, is a member of the Ras superfamily guanine nucleotide exchange factor (GEF) family. It acts as a diacylglycerol (DAG)-regulated nucleotide exchange factor, specifically activating Ras through the exchange of bound GDP for GTP. This activation triggers the Erk/MAP kinase cascade and regulates T-cells and B-cells development, homeostasis, and differentiation. Alternative splicing produces different isoforms of the protein. A shorter transcript, lacking a 5-prime exon, is present in rats but not in humans. A defective RASGRP1 gene has been linked to recurrent infections in a 12-year-old patient. RASGRP1 also plays a role in the functions of natural killer cell dyneins.
RASGRP1 acts as a nucleotide exchange factor, specifically activating Ras by replacing bound GDP with GTP. This activation is triggered by calcium and diacylglycerol (DAG). It initiates the Erk/MAP kinase cascade and plays a crucial role in regulating T-cell and B-cell development, homeostasis, and differentiation by linking T-lymphocyte and B-lymphocyte antigen receptors to Ras. Additionally, it controls NK cell cytotoxicity and ITAM-dependent cytokine production through the Ras-mediated ERK and JNK pathways. RASGRP1 is involved in mast cell degranulation and cytokine secretion, regulating FcERI-evoked allergic responses. It might also participate in the differentiation of other cell types.
RASGRP1 is also known as CALDAG-GEFI, CALDAG-GEFII, IMD64, RASGRP.
