spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Movies
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Reedy, M. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Reedy, M. C.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Journal of Cell Science, Vol 113, Issue 20 3551-3562, Copyright © 2000 by Company of Biologists

JOURNAL ARTICLES

Visualizing myosin's power stroke in muscle contraction

MC Reedy
Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA. mary.reedy@cellbio.duke.edu

The long-standing swinging crossbridge or lever arm hypothesis for the motor action of myosin heads finds support in recent results from 3-D tomograms of insect flight muscle (IFM) fast frozen during active contraction and from both fluorescence polarization and X-ray diffraction during rapid stretches or releases of isometrically contracting fibers. The latter provide direct evidence for lever arm movements synchronous with force changes. Rebuilding the atomic model of nucleotide-free subfragment 1 (S1) to fit fast-frozen, active IFM crossbridges suggests a two-stage power stroke in which the catalytic domain rolls on actin from weak to strong binding; this is followed by a 5-nm lever arm swing of the light chain domain, which gives a total interaction distance of approx. 12 nm. Comparison of S1 crystal structures with in situ myosin heads suggests that actin binding may be necessary in order to view the full repertoire of myosin motor action. The differing positions of the catalytic domains of actin-attached myosin heads in contracting IFM suggest that both the actin-myosin binding energy and the hydrolysis of ATP may be used to cock the crossbridge and drive the power stroke.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:


Home page
 Proc. Natl. Acad. Sci. USAHome page
J. S. Davis and N. D. Epstein
Mechanistic role of movement and strain sensitivity in muscle contraction
PNAS, April 14, 2009; 106(15): 6140 - 6145.
[Abstract] [Full Text] [PDF]

Home page
 BloodHome page
X. Lu, J. Chen, R. Malumbres, E. Cubedo Gil, D. M. Helfman, and I. S. Lossos
HGAL, a lymphoma prognostic biomarker, interacts with the cytoskeleton and mediates the effects of IL-6 on cell migration
Blood, December 15, 2007; 110(13): 4268 - 4277.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 2000