Summary
Phosphorylation of the regulatory light chain of smooth muscle myosin efficiently regulates the actin-activated ATPase activity of myosin filaments in solution and actin movement in an in vitro motility assay, independently of thin-filament regulatory proteins. Filaments containing both phosphorylated and dephosphorylated heads move actin at intermediate rates, depending on the relative proportions of the two myosin species. The decrease in velocity can be accounted for by mechanical interaction; between phosphorylated heads and ‘weak-binding’ dephosphorylated crossbridges. These results imply that shortening velocity could be modulated in any muscle by varying the relative proportions of two populations of crossbridges with different cycling rates.
- © The Company of Biologists Limited 1991
Article navigation
Related articles
Cited by...
More in this TOC section
Similar articles
Other journals from The Company of Biologists
First person – Dougall Norris
“[…] ask yourself: what am I investigating that is novel, why is it necessary and am I confident I can't learn more from the literature first?”
The next in our new series of interviews features Dougall Norris, first author on a Tools and resources article describing an improved fusion protein for visualising membrane recruitment of Akt2 in adipocytes.
Catch up with more of our first authors on our interviews page.
Cell science at a glance – Emerging functions of the Fanconi anemia pathway at a glance
In their poster and associated article, Rhea Sumpter, Jr and Beth Levine reveal recently discovered links between the Fanconi anemia pathway and selective autophagy of viruses and mitochondria.
Featured article – Nonmuscle myosin takes to the heart
Xuefei Ma, Robert Adelstein and co-workers address the role of NMIIB in epicardial formation and EMT in mice. Their Research article shows that knockout of NMIIB leads to a disruption of epicardial integrity, a loss of E-cadherin at cell−cell junctions and focal detachment of epicardial cells from the myocardium.
Review – Control mechanisms in germ cells mediated by p53 family proteins
Members of the p53 protein family have important roles in quality control processes within germ cells. In this Review article, Volker Dötsch and colleagues discuss these roles, in particular that of p63 and its molecular control mechanisms.
Travelling fellowship – Visualising the bacterial cytoskeleton
A Travelling Fellowship from JCS allowed Sina Krokowski from Imperial College London to travel the lab of pioneering bacterial cytoskeleton expert Dr Rut Carballido-López at INRA, France. There, Sina was able to develop her skills in bacterial cell biology techniques and expand her knowledge of microbial genetics. Read her story here.
Where could your research take you? The deadline for the current round of applications for a JCS Travelling Fellowship is 31 August. Find out more here.