CASQ1
CASQ1 (calsequestrin-1) is the skeletal muscle member of the calsequestrin family, a high-capacity calcium-binding protein that acts as an internal calcium store in muscle. It is also known as calmitine, PDIB1, CSQ1 and CASQ. Browse Assay Genie's current range of CASQ1 research reagents below, or read on for the biology behind the target.
CASQ1 is a high-capacity, moderate-affinity calcium-binding protein that serves as an internal calcium store in muscle. Calcium ions are bound by clusters of acidic residues at the protein surface, often at the interface between subunits, and a single molecule can bind around 80 Ca(2+) ions. CASQ1 also regulates the release of lumenal Ca(2+) through the calcium release channel RYR1, which plays an important role in triggering muscle contraction, and it negatively regulates store-operated Ca(2+) entry (SOCE) activity.
The CASQ1 gene encodes the skeletal muscle-specific member of the calsequestrin protein family. Calsequestrin functions as a luminal sarcoplasmic reticulum calcium sensor in both cardiac and skeletal muscle cells. UniProt records the protein in the endoplasmic reticulum, the sarcoplasmic reticulum lumen and membrane, and the mitochondrial matrix. In the mitochondria of skeletal muscle it is reported to act as a calcium regulator, under the name calmitine.
HGNC places CASQ1 in the protein disulfide isomerases gene group, and lists PDIB1, CSQ1 and CASQ as aliases. The previous name was calsequestrin 1 (fast-twitch, skeletal muscle). The CASQ1 protein is absent in patients with Duchenne and Becker types of muscular dystrophy, which makes it a point of interest in studies of dystrophic muscle. Mouse and rat both carry a Casq1 ortholog.
CASQ1 acts as a high-capacity internal calcium store, so it is central to studies of how muscle cells hold and release calcium.
CASQ1 regulates release of lumenal Ca(2+) via RYR1, a step that helps trigger muscle contraction.
CASQ1 negatively regulates store-operated Ca(2+) entry activity, making it relevant to work on calcium signalling in muscle.
CASQ1 is absent in patients with Duchenne and Becker muscular dystrophy, linking it to investigation of dystrophic muscle.
CASQ1 is a high-capacity, moderate-affinity calcium-binding protein that acts as an internal calcium store in muscle, binding around 80 Ca(2+) ions. It regulates lumenal Ca(2+) release through RYR1, helping trigger muscle contraction, and negatively regulates store-operated Ca(2+) entry.
CASQ1 is also called calsequestrin-1, calmitine, PDIB1, CSQ1 and CASQ. Its previous HGNC name was calsequestrin 1 (fast-twitch, skeletal muscle). Calmitine refers to the protein's reported role as a calcium regulator in skeletal muscle mitochondria.
CASQ1 is absent in patients with Duchenne and Becker types of muscular dystrophy. Mouse and rat each have a Casq1 ortholog, so rodent models are used for study. Check the datasheet of any product for its validated reactivity.
Other calsequestrin family members, calcium-release channels and muscle disease markers with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P31415; product specifications from Assay Genie datasheets.