Читать книгу Vitamin D in Clinical Medicine - Группа авторов - Страница 50

The DBP belongs to the albuminoid gene family, initially denominated as a groupspecific component (Gc-globulin). It is a 458-amino acid multifunctional protein with 51- to 58-kDa molecular weight, synthesized by the liver, and secreted into circulation in large concentrations. It is the major transporter of vitamin D metabolites and exhibits different affinity for the multiple compounds. Although vitamin D binding is the main function of DBP, and even responsible for its name, the protein has another important function, which makes its physiology unique and complex. Actin scavenging is a known vital function of DBP, important to avoid actin polymerization and, consequently, tissue damage. Also considered an acute phase reactant, DBP is the precursor of signal MAF (Gc-MAF). Furthermore, DBP is highly polymorphic, with a characteristic distribution among different racial groups. Although its concentration is closely related to the total 25(OH)D, the relevance of the free and bound circulating hormone in human physiology remains unclear.