Mouse S100A6 (also prolactin receptor-associated protein and calcyclin) is a 10 kDa member of the S100 family of calcium-binding proteins. S100A6 is 89 amino acids (aa) in length and contains two calcium-binding EF-hand domains (aa 12 - 47 and 48 - 83). Intracellularly, S100A6 will both noncovalently homodimerize and heterodimerize with S100B plus SGT1. Extracellularly, S100A6 is secreted via a noncanonical pathway and binds to RAGE, inducing apoptosis. It is expressed by neurons, endothelium, fibroblasts, and glandular epithelia. Mouse S100A6 is 99% and 96% aa identical to rat and human S100A6, respectively.