Crystal structure of the murine NK cell-activating receptor NKG2D at 1.95 angstrom

NKG2D, a homodimeric lectin-like receptor, is a unique stimulatory molecule that is found on natural killer cells,T cells and activated macrophages. T he natural ligands for murine NKG2D are distant major histocompatibility co mplex homologs, retinoic acid early transcript (Rael) and H-60 minor histoc ompatibility antigen. The crystal structure of the extracellular region of murine NKG2D reveals close homology with other C-type lectin receptors such as CD94, Ly49A, rat MBP-A and CD69, However, the precise mode of dimeric a ssembly varies among these natural killer receptors, as well as their surfa ce topography and electrostatic properties,The NKG2D structure provides the first structural insights into the role and ligand specificity of this sti mulatory receptor in the innate and adaptive immune system.