This family of proteins represents M157,a divergent form of MHC class I-like proteins which is the protein product of the mouse cytomegalovirus. This protein is unique in its ability to engage both activating (Ly49H) and inhibitory (Ly49I) natural killer cell receptors. M157 is involved in intra- and intermolecular interacts within and between its domains to form a compact MHC-like molecule.
Jiyao W et al.(2023). "The conserved domain database in 2023.",