Localization and Characterization of a 7.3-kDa Region of Caldesmon Which Reversibly Inhibits Actomyosin ATPase Activity
Author
Chalovich, Joseph; Bryan, Joseph; Benson, Caryl E.; Velaz, Laly
Abstract
Cleavage of caldesmon with chymotrypsin yields a series of fragments which bind both calmodulin and actin and inhibit the binding of myosin subfragments to actin and the subsequent stimulation of ATPase activity. Several of these fragments have been purified by cation exchange chromatography and their amino-terminal sequences determined. The smallest fragment has a molecular mass of about 7.3 kDa and extends from Leu597 to Phe665. This polypeptide inhibits the actin-activated ATPase of myosin S-1; this inhibition is augmented by smooth muscle tropomyosin and relieved by Ca2+- calmodulin. The binding of the 7.3-kDa fragment to actin is competitive with the binding of S - 1 to actin. Thus, this polypeptide has several of the important features characteristic of intact caldesmon. However, although an intact caldesmon molecule covers between six and nine actin monomers, the 7.3-kDa fragment binds to actin in a 1:1 complex. Comparison of this fragment with others suggests that a small region of caldesmon is responsible for at least part of the interaction with both calmodulin and actin. Originally published in the Journal of Biological Chemistry, vol. 267, No. 23, 1992
Subject
Date
1992-08-15
Citation:
APA:
Chalovich, Joseph, & Bryan, Joseph, & Benson, Caryl E., & Velaz, Laly. (August 1992).
Localization and Characterization of a 7.3-kDa Region of Caldesmon Which Reversibly Inhibits Actomyosin ATPase Activity.
Journal of Biological Chemistry,
267(23),
16644-
16650. Retrieved from
http://hdl.handle.net/10342/2993
MLA:
Chalovich, Joseph, and Bryan, Joseph, and Benson, Caryl E., and Velaz, Laly.
"Localization and Characterization of a 7.3-kDa Region of Caldesmon Which Reversibly Inhibits Actomyosin ATPase Activity". Journal of Biological Chemistry.
267:23. (16644-16650),
August 1992.
September 21, 2023.
http://hdl.handle.net/10342/2993.
Chicago:
Chalovich, Joseph and Bryan, Joseph and Benson, Caryl E. and Velaz, Laly,
"Localization and Characterization of a 7.3-kDa Region of Caldesmon Which Reversibly Inhibits Actomyosin ATPase Activity," Journal of Biological Chemistry 267, no.
23 (August 1992),
http://hdl.handle.net/10342/2993 (accessed
September 21, 2023).
AMA:
Chalovich, Joseph, Bryan, Joseph, Benson, Caryl E., Velaz, Laly.
Localization and Characterization of a 7.3-kDa Region of Caldesmon Which Reversibly Inhibits Actomyosin ATPase Activity. Journal of Biological Chemistry.
August 1992;
267(23):
16644-16650.
http://hdl.handle.net/10342/2993. Accessed
September 21, 2023.
Collections
Publisher
East Carolina University