RASGRP4
Developmental stage
Expressed early during development. Detected in all fetal tissues tested.
Domain
The phorbol-ester/DAG-type zinc finger mediates the binding and the functional activation by DAG.
Function
Functions as a cation- and diacylglycerol (DAG)-regulated nucleotide exchange factor activating Ras through the exchange of bound GDP for GTP (PubMed:11880369, PubMed:11956218, PubMed:12493770, PubMed:18024961). In neutrophils, participates in a phospholipase C-activating N-formyl peptide-activated GPCR (G protein-coupled receptor) signaling pathway by promoting Ras-mediated activation of PIK3CG/PI3Kgamma to promote neutrophil functional responses (By similarity). In CD117(+) dendritic cells and mast cells, participates in an lipopolysaccharide (LPS)-activated signaling pathway that stimulates the production of interferon-gamma and other pro-inflammatory cytokines by natural killer (NK) cells (By similarity). May function in mast cell differentiation (PubMed:11880369, PubMed:11956218, PubMed:12493770, PubMed:18024961). Does not appear to be required for the development of B-cells, DC-cells, T-cells, or NK-cells (By similarity).
Sequence Similarities
Belongs to the RASGRP family.
Tissue Specificity
Expressed by mast cells and their progenitors (at protein level). Specifically expressed in mononuclear leukocytes. Highly expressed in myeloid cells compared to lymphoid cells. Also detected in heart, skeletal muscle, spleen, liver, placenta and lung. Not detected in brain. Isoform 1 is the major isoform in normal individuals. Isoform 2 is more significantly expressed in a patient with asthma. Isoform 3 is more significantly expressed in a patient with asthma and a mastocytosis patient.
Cellular localization
- Cytoplasm
- Cell membrane
- Recruited to membranes upon activation by DAG.
Alternative names
RAS guanyl-releasing protein 4, RASGRP4