S100 calcium-binding protein A5 (S100A5)

S100 calcium-binding protein A5 (S100A5) is a member of the S100 family of proteins characterized by two EF-hand calcium-binding motifs[1][3][6]. It has unusually high affinity for Ca²⁺ (20- to 100-fold higher than other S100 proteins) and can also bind Zn²⁺ and Cu²⁺, with strong Cu²⁺ binding inhibiting Ca²⁺ binding[1][3][6]. S100A5 is expressed in restricted regions of the adult brain, including the olfactory bulb and parts of the brain stem[1][5]. Like other S100 proteins, S100A5 is localized in the cytoplasm and/or nucleus and is involved in regulating a range of cellular processes, notably cell cycle progression and differentiation[1][3][6]. Upon calcium activation, S100A5 can interact with the receptor for advanced glycation end products (RAGE), suggesting a role in inflammation signaling[6]. While some S100 proteins are implicated in diseases such as cancer, inflammation, and neurodegeneration, specific disease associations for S100A5 remain limited, though related family links have been noted[3][5][6]. There are currently no known drugs or approved biomarkers directly targeting S100A5.

Other names

Protein S100-A5S100DProtein S-100DS100 calcium-binding protein A5protein S100-A5S100A5