Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
21
|
pubmed:dateCreated |
1988-8-19
|
pubmed:abstractText |
Evidence for a slowly dissociating tubulin-GTP cap at microtubule ends was derived from observation of a delay for attaining a maximum disassembly rate, after the temperature of steady state microtubules was rapidly decreased from 36 to 34 degrees C. The possibility that the microtubules were capped by a single tubulin-GTP subunit on each subhelix was ruled out, by comparison of the disassembly kinetics following a temperature decrease and dilution. The existence of a subpopulation of microtubules that underwent irreversible or near irreversible disassembly was demonstrated by a 30-s lag for attainment of a maximum assembly rate, after steady state microtubules were shifted from 34 to 36 degrees C. A dynamic instability model predicts that a maximum assembly rate will be delayed until disappearance of a subpopulation of microtubules that disassemble before being recapped. Analysis indicates that the 30-s lag resulted because approximately 2% of the mass in the steady state microtubule population was uncapped and disassembling and not readily recapped. The half-time for recapping of disassembling microtubules, by addition of tubulin-GTP subunits to ends, was equal to or greater than 20 s. Since tubulin-GDP dissociated from microtubules at a rate of about 4500 s-1, slow recapping resulted in dramatic shortening of disassembling microtubules.
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Jul
|
pubmed:issn |
0021-9258
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
25
|
pubmed:volume |
263
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
10344-52
|
pubmed:dateRevised |
2007-11-14
|
pubmed:meshHeading |
pubmed-meshheading:3392017-Animals,
pubmed-meshheading:3392017-Brain,
pubmed-meshheading:3392017-Cattle,
pubmed-meshheading:3392017-Guanosine Triphosphate,
pubmed-meshheading:3392017-Kinetics,
pubmed-meshheading:3392017-Macromolecular Substances,
pubmed-meshheading:3392017-Microtubule Proteins,
pubmed-meshheading:3392017-Microtubules,
pubmed-meshheading:3392017-Thermodynamics,
pubmed-meshheading:3392017-Tubulin
|
pubmed:year |
1988
|
pubmed:articleTitle |
Temperature-jump studies of microtubule dynamic instability.
|
pubmed:affiliation |
Department of Biochemistry, University of North Carolina, Chapel Hill 27599-7260.
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
|