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: Heat (30 degrees C)-desensitization of Akazara striated adductor myosin, and its resensitization.
    Author: Ojima T, Nishita K, Watanabe S.
    Journal: J Biochem; 1983 Feb; 93(2):607-13. PubMed ID: 6132920.
    Abstract:
    In a previous report (J. Biochem. 89, 1333-1335, 1981) we showed that 30 degrees C-treatment (pCa less than 6 and 2 mM MgCl2), like EDTA-treatment, caused a reversible removal of regulatory light-chains from Akazara adductor myosin. Utilizing the heat-treatment, we now show (a) that not half but the total removal of regulatory light-chains from Akazara myosin is required for a complete loss of calcium sensitivity of myosin-ATPase, and (b) that recombination of not 1 but 2 mol of regulatory light-chains is required for a full recovery of calcium sensitivity of both myosin-ATPase and actomyosin-superprecipitation. These (a, b) are what we showed previously with EDTA-treatment (J. Biochem. 85, 1543-1546, 1979 and 86, 663-673, 1979), thus establishing that in all respects we tested, the heat-treatment is as good as EDTA-treatment for reversible removal of regulatory light-chains. We also show that the presence of actin during heat-treatment of myosin prevented regulatory light-chains from being released (at pCa 7) and that how well the release was prevented depended on the MgCl2 concentration during the heat-treatment.
    [Abstract] [Full Text] [Related] [New Search]