Calbindin is a calcium-binding protein belonging to the troponin C superfamily. It was originally described as a 27-kDa protein induced by vitamin D in the duodenum of the chick. In the brain, its synthesis is independent of vitamin-D-derived hormones. Calbindin contains 4 active calcium-binding domains, and 2 modified domains that presumably have lost their calcium-binding capacity. Alternative Names: Calbindin 1 28kDa protein, D28K protein, CAB27 protein, Neuronal Marker, D 28K protein, CALB1 protein, Calbindin D28 protein, CALB protein, CALB 1 protein