Linked Life Data

3607064

Source:http://linkedlifedata.com/resource/pubmed/id/3607064

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1987-9-8
pubmed:abstractText
Much interest has currently been attached to the length distribution of microtubules polymerized in vitro and the related question of their possible 'dynamic instability'. Fundamental to this question is the mechanism of microtubule nucleation, which controls the rates of assembly and disassembly of microtubule protein in vitro. These kinetics are affected by a number of factors, including both the guanine nucleotides, GTP and GDP, and magnesium ion. Mg2+ exerts complex effects, as indicated by the existence of an optimal Mg2+ concentration for the maximum assembly rate of microtubule protein, and we investigate these effects in this report. At [Mg2+] greater than 0.5 mM, the characteristic lag-phase is substantially increased and the rate of assembly is greatly reduced without affecting the critical concentration significantly. We show that increasing [Mg2+] has two effects on the assembly process: nucleation is less efficient and the intrinsic rate constant for the elongation reaction is reduced. Lowering [Mg2+] (less than 0.5 mM) also inhibits nucleation. These effects of varying [Mg2+] can be explained predominantly in terms of enhanced stability of the microtubule-associated protein-containing oligomeric species present in the microtubule protein preparation. [Mg2+] is thus found to be a further important factor in microtubule nucleation, and hence, in determining length distributions in assembling microtubules.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
914
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
96-100
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Magnesium ion effects on microtubule nucleation in vitro.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't