Linked Life Data

15450296

Source:http://linkedlifedata.com/resource/pubmed/id/15450296

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-9-28
pubmed:abstractText
As a first step toward freeze-trapping and 3-D modeling of the very rapid load-induced structural responses of active myosin heads, we explored the conformational range of longer lasting force-dependent changes in rigor crossbridges of insect flight muscle (IFM). Rigor IFM fibers were slam-frozen after ramp stretch (1000 ms) of 1-2% and freeze-substituted. Tomograms were calculated from tilt series of 30 nm longitudinal sections of Araldite-embedded fibers. Modified procedures of alignment and correspondence analysis grouped self-similar crossbridge forms into 16 class averages with 4.5 nm resolution, revealing actin protomers and myosin S2 segments of some crossbridges for the first time in muscle thin sections. Acto-S1 atomic models manually fitted to crossbridge density required a range of lever arm adjustments to match variably distorted rigor crossbridges. Some lever arms were unchanged compared with low tension rigor, while others were bent and displaced M-ward by up to 4.5 nm. The average displacement was 1.6 +/- 1.0 nm. "Map back" images that replaced each unaveraged 39 nm crossbridge motif by its class average showed an ordered mix of distorted and unaltered crossbridges distributed along the 116 nm repeat that reflects differences in rigor myosin head loading even before stretch.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1047-8477
pubmed:author
pubmed:copyrightInfo
Copyright 2004 Elsevier Inc.
pubmed:issnType
Print
pubmed:volume
147
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
268-82
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Electron tomography of fast frozen, stretched rigor fibers reveals elastic distortions in the myosin crossbridges.
pubmed:affiliation
Institute of Molecular Biophysics, Florida State University, Tallahassee, FL 32306-4380, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't