Ly49G is a type II transmembrane protein belonging to the family of Ly49 proteins, each having specificity for a small repertoire of MHC I alleles that are generally recognized in a peptide-independent manner. The Ly49 family of MHC class I receptors shows a high degree of variability between mouse strains. It is expressed on a subset of NK cells and some NKT cell lines. The AT8 antibody reacts with the Ly49G receptor from BALB/c, 129/J, 129Sv/J, SJL, FVB/N, A/J, C3H/HeJ, C3H/HeNCr, CBA/J, and CBA/NCr mice.