Plays an inhibitory role on natural killer (NK) cells and T-cell functions upon binding to their non-MHC ligands. May mediate missing self recognition by binding to a highly conserved site on classical cadherins, enabling it to monitor expression of E-cadherin/CDH1, N-cadherin/CDH2 and R-cadherin/CDH4 on target cells. Forms a monomer and homodimer; disulfide-linked (By similarity). Interacts (via ITIM motif) with PTPN11 and INPP5D. Expressed specifically on natural killer (NK) cells and activated CD8 T-cells. Not detected in spleen, thymus, lymph node, testis, brain or kidney. Not detected on mast cell lines, bone marrow-derived mast cells, or peritoneal mast cells. By pathogens and viruses infections. Contains 1 copy of a cytoplasmic motif that is referred to as the immunoreceptor tyrosine-based inhibitor motif (ITIM). This motif is involved in modulation of cellular responses. Upon phosphorylation of ITIM motif KLRG1 associates with the two phosphatases, PTPN11 and INPP5D. Phosphorylated in response to monoclonal antibody G63 binding and antigenic stimulation. MCFA