FCER1G
Description
The FCER1G (Fc epsilon receptor Ig) is a protein-coding gene located on chromosome 1.
The Fc fragment of IgE, high affinity I, receptor for; gamma polypeptide is the gamma chain of the high affinity IgE receptor. This protein is encoded by the FCER1G gene in humans. The high affinity IgE receptor, FcεRI, is a key molecule involved in allergic reactions. It is a tetramer composed of 1 alpha, 1 beta, and 2 gamma chains. The gamma chains are also subunits of other Fc receptors.
The FCER1G gene encodes a protein that acts as an adapter protein with an immunoreceptor tyrosine-based activation motif (ITAM). This motif is crucial for transmitting activation signals from various immune receptors. In the context of the high-affinity immunoglobulin E (IgE) receptor, FCER1G plays a key role in mediating allergic inflammatory responses within mast cells. As a constituent of the interleukin-3 receptor complex, FCER1G selectively regulates interleukin 4 (IL4) production by basophils, thereby priming T-cells to differentiate into effector T-helper 2 cells. Notably, FCER1G associates with pattern recognition receptors CLEC4D and CLEC4E, forming a functional signaling complex within myeloid cells. The binding of mycobacterial trehalose 6,6'-dimycolate (TDM) to this receptor complex triggers phosphorylation of the ITAM, subsequently activating SYK, CARD9, and NF-kappa-B. This activation pathway drives the maturation of antigen-presenting cells and influences the differentiation of T-cells toward effector T-helper 1 and T-helper 17 subtypes. FCER1G may also collaborate with other activating receptors. Moreover, it is functionally linked to integrin beta-2/ITGB2-mediated neutrophil activation and implicated in integrin alpha-2/ITGA2-mediated platelet activation.
FCER1G is also known as FCRG.