Functional domain of caldesmon

• Published in: FEBS letters Vol. 202; no. 2; pp. 182 - 186
• Main Authors: Szpacenko, Adam, Dąbrowska, Renata
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 07.07.1986; Elsevier
• Subjects: Adenosine Triphosphatases - metabolism; Analytical, structural and metabolic biochemistry; Animals; Binding and carrier proteins; Binding Sites; Biological and medical sciences; Calcium - metabolism; Caldesmon; Calmodulin - metabolism; Calmodulin-Binding Proteins - analysis; Chicken gizzard; Chickens; Chymotrypsin - metabolism; Chymotryptic cleavage; Electrophoresis, Polyacrylamide Gel; Functional domain; Fundamental and applied biological sciences. Psychology; gizzard; Gizzard, Avian - enzymology; Molecular Weight; Peptide Fragments - analysis; Proteins; proteolysis; Rabbits; Structure-Activity Relationship; Functional domain; Chicken gizzard; Caldesmon; Chymotryptic cleavage; Binding protein; Vertebrata; Gizzard; Enzymatic digestion; Chicken; Aves; Structure function relationship
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(86)80683-4

Limted proteolysis of caldesmon has been used in studying the structure-function relationship of this protein. Digestion with α-chymotrypsin yields three major fragments of 110, 80 and 40 kDa. Only the 40 kDa fragment preserves functional properties of the parent molecule: it binds to F-actin, causes inhibition of actomyosin ATPase and binds to calmodulin in a Ca 2+-dependent manner. Its further degradation produces an 18 kDa polypeptide that also retains all these properties. Neither F-actin nor calmodulin binding induces dramatic changes in susceptibility to chymotryptic cleavage and the sites of cleavage of caldesmon.