Calcium-Binding Proteins: Cytosolic (Annexins, Gelsolins, and C2-Domain Proteins)

Abstract

Calcium is a very versatile second messenger involved in the regulation of a variety of different cellular processes. This is made possible due to the binding of Ca2+ to a great variety of different calcium-binding proteins, such as calcium-buffering or calcium-sensing proteins; the latter are also known as EF-hand containing proteins. In addition, a number of other calcium-binding proteins have been studied in recent years. In this article the families of annexins, gelsolins, and C2-domain containing proteins are described. These proteins are composed of a number of repeat units containing a variety of different Ca2+-binding sites. They bind to membranous or cytoskeletal structures in a Ca2+-dependent manner, and are involved in a number of different cellular functions. The importance of those proteins is underlined by their malfunction, leading to different diseases including cancer.