Ryanodine receptor

Ryanodine receptors (RyR) are classified as high-conductance, intracellular calcium release channels, typically present in the membrane of the sarcoplasmic and endoplasmic reticulum. The major role these channels play is to regulate cell signaling and muscle contraction by releasing calcium ions. There are three major isoforms of the ryanodine receptor (RyR1, RyR2, and RyR3), which are found in different tissues and participate in various signaling pathways involving calcium release from intracellular organelles. RyR1 is responsible for skeletal muscle contraction, RyR2 is responsible for cardiac muscle contraction, and RyR3 is responsible for maintaining calcium homeostasis in the brain and throughout other tissues in the body.