calponin homology (CH) domain found in the calponin family
Calponin is an actin filament-associated regulatory protein expressed in smooth muscle and many types of non-muscle cells. There are three calponin isoforms, calponin-1, -2, -3. All of them are actin-binding proteins with functions in inhibiting actin-activated myosin ATPase and stabilizing the actin cytoskeleton. Calponin-1 is specifically expressed in smooth muscle cells and plays a role in fine-tuning smooth muscle contractility. Calponin-2 is expressed in both smooth muscle and non-muscle cells and regulates multiple actin cytoskeleton-based functions. Calponin-3 is expressed in the brain and participates in actin cytoskeleton-based activities in embryonic development and myogenesis. Members of this family contain a single copy of the CH domain. CH domains are actin filament (F-actin) binding motifs.
Jiyao W et al.(2023). "The conserved domain database in 2023.",