Qa-1b

Qa-1b is a Murine MHC class Ib molecule and is the functional homology of HLA-E in human. Qa-1b is characterised by its limited polymorphisms and small peptide repertoire peptide presented. Qa-1b binds to peptides derived from Murine MHC class Ib molecule and interact with Murine CD94/NKG2 receptors on natural killer cells. The leader peptide-bound Qa-1b signals natural killer cells not to engage in cell lysis. Despite of its homology with HLA-E, it seems that the Qa-1b has coincidentally evolved to have a similar function to HLA-E.