S100 Calcium Binding Protein A5 (S100A5)

S100 calcium binding protein A5 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100 genes include at least 13 members which are located as a cluster on chromosome 1q21.

This protein has a Ca2 affinity 20- to 100-fold higher than the other S100 proteins studied under identical conditions. This protein also binds Zn2 and Cu2 , and Cu2 strongly which impairs the binding of Ca2 . This protein is expressed in very restricted regions of the adult brain.