• Source: Calponin

Calponin is a calcium binding protein. Calponin tonically inhibits the ATPase activity of myosin in smooth muscle. Phosphorylation of calponin by a protein kinase, which is dependent upon calcium binding to calmodulin, releases the calponin's inhibition of the smooth muscle ATPase.




Structure and function


Calponin is mainly made up of α-helices with hydrogen bond turns. It is a binding protein and is made up of three domains. These domains in order of appearance are Calponin Homology (CH), regulatory domain (RD), and Click-23, domain that contains the calponin repeats. At the CH domain calponin binds to α-actin and filamin and binds to actin within the RD domain. Calmodulin, when activated by calcium may bind weakly to the CH domain and inhibit calponin binding with α-actin. Calponin is responsible for binding many actin binding proteins, phospholipids, and regulates the actin/myosin interaction. Calponin is also thought to negatively affect the bone making process due to being expressed in high amounts in osteoblasts.




References






External links


Calponin at the U.S. National Library of Medicine Medical Subject Headings (MeSH)

Kata Kunci Pencarian:

• Calponin 2
• Calponin
• Calponin 1
• Calponin homology domain
• Calponin 3, acidic
• Calponin family repeat
• Fimbrin
• Smooth muscle
• Chromatophore
• Plastin