Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-1-5
pubmed:abstractText
Neuromuscular acetylcholine receptors are synaptic ion channels that open and close with rate constants of approximately equal to 48,000 s(-1) and approximately equal to 1,700 s(-1), respectively (in adult mouse, at 24 degrees C, -100 mV membrane potential). Perturbations of many different sites in the protein can change these rate constants, with those in the extracellular domain mainly affecting channel-opening and many of those in the membrane and intracellular domains mainly affecting channel-closing. We used single-channel recordings to measure the total open time per activation (tau(b)) elicited by a low concentration of the natural transmitter, acetylcholine. tau(b) increased in constructs with mutations that increased the gating equilibrium constant by either increasing the opening or decreasing the closing rate constant. However, tau(b) did not approach the same asymptote in fast-opening and slow-closing constructs. The maximum value for the slow closers was about twice that for the fast openers. One interpretation of this difference is that there is an upper limit to the channel-opening rate constant, which we estimate to be approximately 0.86 mus(-1). One possibility is that this limit is the rate of conformational change in the absence of an overall activation barrier and thus reflects the kinetic prefactor for the acetylcholine receptor opening isomerization.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10449738, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10468632, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10693806, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10779319, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10860987, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10940252, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-10962011, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11087839, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11205343, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11357122, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11717464, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11836518, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-11969415, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-12042345, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-12384704, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-12594518, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-12646702, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-12770877, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-14557402, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-14674774, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-14990476, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-15051806, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-15458639, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-1615323, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-1637808, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-1689592, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-22856, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-7552728, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-8038403, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-8650166, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-8770203, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-8901868, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-9222901, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-9615170, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-9729627, http://linkedlifedata.com/resource/pubmed/commentcorrection/15618401-9929481
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
102
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-92
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
A speed limit for conformational change of an allosteric membrane protein.
pubmed:affiliation
Center for Single Molecule Biophysics and Department of Physiology and Biophysics, State University of New York, Buffalo, NY 14214, USA.
pubmed:publicationType
Journal Article