Calpain
Calpains are a family of calcium-dependent cysteine proteases found in eukaryotes. They are involved in a wide range of cellular processes, including muscle contraction, cell proliferation, apoptosis, and signal transduction. Calpains are activated by an increase in intracellular calcium concentration, which binds to regulatory subunits of the enzyme. This binding event triggers a conformational change that exposes the active site, allowing the calpain to cleave its target proteins.
There are numerous calpain isoforms in mammals, with the most well-studied being calpain 1 and calpain 2.
Dysregulation of calpain activity has been implicated in various pathological conditions, including neurodegenerative diseases, muscular dystrophies,