SH2D1A : SH2 domain containing 1A
Description
The SH2D1A (SH2 domain containing 1A) is a protein-coding gene located on chromosome X.
The SH2D1A gene provides instructions for making a protein called signaling lymphocyte activation molecule (SLAM) associated protein (SAP). SAP interacts with other proteins called SLAM family receptors to activate signaling pathways that are involved in the control of immune cells (lymphocytes). In particular, it helps regulate lymphocytes that destroy other cells (cytotoxic lymphocytes) and is necessary for the development of specialized lymphocytes called natural killer T cells. SAP also helps control immune reactions by triggering self-destruction (apoptosis) of lymphocytes when they are no longer needed.
SH2D1A, also known as SAP, functions as a cytoplasmic adapter protein that interacts with and regulates receptors of the SLAM family, including SLAMF1, CD244, LY9, CD84, SLAMF6, and SLAMF7. In SLAM signaling, SAP collaborates with SH2D1B/EAT-2. Initially, it was suggested that SAP's association with SLAMF1 prevents SLAMF1 from binding to inhibitory effectors like INPP5D/SHIP1 and PTPN11/SHP-2. However, through simultaneous interactions, SAP recruits FYN, which subsequently phosphorylates and activates SLAMF1. SAP positively regulates CD244/2B4- and CD84-mediated natural killer (NK) cell functions and can also promote CD48-, SLAMF6-, LY9-, and SLAMF7-mediated NK cell activation. In the context of NK cell-mediated cytotoxicity, SAP enhances conjugate formation with target cells. Additionally, SAP may regulate the activity of neurotrophin receptors NTRK1, NTRK2, and NTRK3.
SH2D1A is also known as DSHP, EBVS, IMD5, LYP, MTCP1, SAP, SAP/SH2D1A, XLP, XLPD, XLPD1.
