These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Characteristics of the myosin and tropomyosin binding regions of the smooth muscle caldesmon.
    Author: Katayama E, Horiuchi KY, Chacko S.
    Journal: Biochem Biophys Res Commun; 1989 May 15; 160(3):1316-22. PubMed ID: 2525036.
    Abstract:
    Limited digestion of caldesmon by alpha-chymotrypsin generates mainly 110, 80, 60, 38, and 28 kDa fragments. Affinity chromatography of these fragments on columns immobilized with myosin, HMM, or tropomyosin showed that the bound fraction from these columns was similar and it contained 110, 80, 60 and 28 kDa fragments. These fragments did not bind to myosin filaments, acto-HMM, actin or tropomyosin-actin in the solution, and they had no effect on the actin-activated ATPase of HMM. In contrast, the flow-through fraction from these affinity columns inhibited the actin-activated ATPase. Binding studies revealed that the 38 kDa fragment and its break down products bound to actin and tropomyosin-actin, and they were released partially from actin by calmodulin with a concomitant increase in the ATPase activity. These results indicate that, unlike the actin binding domain, the myosin and tropomyosin binding domains require the caldesmon molecule to be intact in order to exert their effects on the protein-protein interaction.
    [Abstract] [Full Text] [Related] [New Search]