CD244
Description
The CD244 (CD244 molecule) is a protein-coding gene located on chromosome 1.
CD244 (Cluster of Differentiation 244), also known as 2B4 or SLAMF4, is a protein encoded by the CD244 gene in humans. It's a type-I transmembrane protein belonging to the signaling lymphocytic activation molecule (SLAMF) family, expressed in various hematopoietic cells. CD244 plays a crucial role in regulating the immune system. Its ligand is CD48 (SLAMF2), another SLAMF family member lacking an intracellular domain and anchored to the plasma membrane by a GPI-anchor. CD244 is encoded by the CD244 gene located on chromosome 1. Alternative splicing generates different isoforms of this protein. Initially identified in NK cells, CD244 is also expressed in monocytes, basophils, eosinophils, mast cells, dendritic cells, and T cells. The receptor consists of intracellular, transmembrane, and extracellular domains.
CD244, also known as 2B4 or SLAMF4, is a member of the signaling lymphocytic activation molecule (SLAM) family. It interacts with CD48, another SLAM family member, through heterophilic interactions. SLAM receptors, triggered by cell-cell interactions, modulate the activation and differentiation of various immune cells, regulating both innate and adaptive immune responses. CD244's activity is controlled by the presence or absence of adapter proteins, SH2D1A/SAP and SH2D1B/EAT-2. It acts as an activating receptor on natural killer (NK) cells, stimulating cytotoxicity, IFN-gamma production, and granule exocytosis. This activation is mediated by its association with SH2D1A and FYN, leading to downstream signaling primarily through VAV1 and to a lesser extent through INPP5D/SHIP1 and CBL. In the absence of SH2D1A, signal attenuation occurs primarily through INPP5D and to a lesser extent through PTPN6/SHP-1 and PTPN11/SHP-2. CD244 also acts as a costimulator for NK cell activation, enhancing signals from other NK receptors like NCR3 and NCR1. During early NK cell differentiation, CD244 may function as an inhibitory receptor, potentially ensuring self-tolerance. It contributes to the regulation of CD8(+) T-cell proliferation, acting as a costimulator for neighboring T-cells. Furthermore, CD244 inhibits inflammatory responses in dendritic cells.
CD244 is also known as 2B4, NAIL, NKR2B4, Nmrk, SLAMF4.
