Linked Life Data

7853391

Source:http://linkedlifedata.com/resource/pubmed/id/7853391

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1995-3-16
pubmed:abstractText
We present a model of the actin-tropomyosin complex in which the radial and azimuthal position of tropomyosin was adjusted to fit the X-ray fiber diffraction patterns from oriented actin-tropomyosin gels at a resolution of 1/8 A-1. We used the recently published atomic F-actin model for the calculations. The atomic model of tropomyosin was obtained by model-building a coiled coiled-coil structure from the tropomyosin sequence. The resulting atomic model is strongly preferred and shows strong electrostatic interactions between charged side-chains of tropomyosin residues and actin residues in subdomain 3 and subdomain 4. Furthermore, calculations of enthalpies based upon electrostatic interactions indicate that there is a favored rotational position of the tropomyosin core at the calculated azimuthal and radial position given by the X-ray refinement. Rotations of the tropomyosin strand out of this position turn strongly attractive electrostatic interactions into repulsive forces. The resulting binding radius of 39 A and the determined azimuthal position of tropomyosin are in good agreement with electron microscopy reconstructions and neutron diffraction experiments. Furthermore, the calculated position of tropomyosin would still partly block the rigor interaction of myosin cross-bridges with actin, whereas it very likely allows undisturbed binding of the cross-bridges in a weak binding state.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
246
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
108-19
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
An atomic model of the unregulated thin filament obtained by X-ray fiber diffraction on oriented actin-tropomyosin gels.
pubmed:affiliation
Max-Planck Institut für medizinische Forschung Abteilung Biophysik, Heidelberg, Germany.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.