CASQ2
Function
Calsequestrin is a high-capacity, moderate affinity, calcium-binding protein and thus acts as an internal calcium store in muscle. Calcium ions are bound by clusters of acidic residues at the protein surface, especially at the interface between subunits. Can bind around 60 Ca(2+) ions. Regulates the release of lumenal Ca(2+) via the calcium release channel RYR2; this plays an important role in triggering muscle contraction. Plays a role in excitation-contraction coupling in the heart and in regulating the rate of heart beats.
Involvement in disease
Ventricular tachycardia, catecholaminergic polymorphic, 2
CPVT2
An arrhythmogenic disorder characterized by stress-induced, bidirectional ventricular tachycardia that may degenerate into cardiac arrest and cause sudden death. Patients present with recurrent syncope, seizures, or sudden death after physical activity or emotional stress. CPVT2 inheritance is autosomal recessive.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
Phosphorylation in the C-terminus, probably by CK2, moderately increases calcium buffering capacity.
N-glycosylated.
Sequence Similarities
Belongs to the calsequestrin family.
Cellular localization
- Sarcoplasmic reticulum lumen
- This isoform of calsequestrin occurs in the sarcoplasmic reticulum's terminal cisternae luminal spaces of cardiac and slow skeletal muscle cells.
Alternative names
Calsequestrin-2, CASQ2