Calsequestrin-2 (CASQ2)

Calsequestrin is a high-capacity, moderate affinity, calcium-binding protein and so functions as an internal calcium store in muscle. Calcium ions are bound by clusters of acidic residues in the protein surface, especially at the interface between subunits.

Can bind around 60 Ca(2+) ions. Regulates the discharge of lumenal Ca(2+) through the calcium release channel RYR2; this plays an important role in triggering muscle contraction.