Alteration of the enzymatic properties of smooth muscle myosin by a monoclonal antibody against subfragment 2
- 24 April 1990
- journal article
- Published by Wiley in FEBS Letters
- Vol. 263 (2) , 241-244
- https://doi.org/10.1016/0014-5793(90)81383-y
Abstract
A monoclonal antibody against subfragment 2 (S-2) of smooth muscle myosin, designated MM-9, was generated and characterized. MM-9 potently inhibited subfragment 1 (S-1) release by papain proteolysis of myosin, suggesting that the epitope of MM-9 is at or very close to the S-1/S-2 junction. The depression of Ca2+ - and Mg2+-ATPase activities of myosin at low ionic strength was significantly reduced by MM-9. MM-9 increased the acto dephosphorylated HMM ATPase activity about 3-fold. On the other hand, the antibody had no effect on the KCl-dependence of viscosity of monomeric myosin. These results suggest that the folding of the myosin rod is not the direct determinant of enzymatic activity, and that the subtle conformational change at the S-1/S-2 junction (head-neck region) plays a critical role in determining enzymatic activitiesKeywords
This publication has 13 references indexed in Scilit:
- Correlation of enzymic properties and conformation of bovine erythrocyte myosinBiochemistry, 1989
- Regulation in vitro of brush border myosin by light chain phosphorylationJournal of Molecular Biology, 1986
- Proteolysis of smooth muscle myosin by Staphylococcus aureus protease: preparation of heavy meromyosin and subfragment 1 with intact 20,000-dalton light chainsBiochemistry, 1985
- A monoclonal anti-human platelet antibody: a new platelet aggregating substanceBlood, 1985
- Effects of magnesium chloride on smooth muscle actomyosin adenosine 5'-triphosphatase activity, myosin conformation, and tension development in glycerinated smooth muscle fibersBiochemistry, 1984
- Correlation of enzymatic properties and conformation of smooth muscle myosinBiochemistry, 1983
- Light-chain phosphorylation controls the conformation of vertebrate non-muscle and smooth muscle myosin moleculesNature, 1983
- [30] Smooth muscle myosin light chain kinasePublished by Elsevier ,1983
- A bent monomeric conformation of myosin from smooth muscle.Proceedings of the National Academy of Sciences, 1982
- The contractile proteins of smooth muscle. Properties and components of a Ca2+-sensitive actomyosin from chicken gizzardArchives of Biochemistry and Biophysics, 1975