Linked Life Data

11545589

Source:http://linkedlifedata.com/resource/pubmed/id/11545589

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-9-7
pubmed:abstractText
Individual microtubules (MTs) repeat alternating phases of polymerization and depolymerization, a process known as dynamic instability. Microtubule-associated proteins (MAPs) regulate the dynamic instability by increasing the rescue frequency. To explore the influence of MAP2 on in vitro MT dynamics, we correlated the distribution of MAP2 on individual MTs with the dynamic phase changes of the same MTs. MAP2 was modified selectively on its projection region by X-rhodamine iodoacetamide without altering the MT-binding activity. When the labeled MAP2 was added to MTs, the fluorescence was distributed along almost the entire length of individual MTs. However, the inhomogeneity of the distribution gradually became obvious due to the fluorescence bleaching, and the MTs appeared to consist of rapidly bleached portions (RBPs) and slowly bleached portions (SBPs), which were distributed randomly along the MT. By measuring the duration of fluorescence bleaching, the density of MAP2 in SBP was estimated to be approximately 2.5 times higher than the RBP. The average tubulin:MAP2 ratio in SBP was calculated to be 16. When the MT dynamics were observed by dark-field microscopy after determining the MAP2 distribution, rescues were always found to occur only at the SBPs. MTs also displayed intermittent shortening by repeated depolymerization phases separated by pause phases. In these cases, depolymerization phases stopped only at the SBPs. Not every SBP stopped depolymerization, but depolymerization always stopped at an SBP. Taken together, we suggest that there is a minimum density of MAP2 that is necessary to stop depolymerization.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Academic Press.
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
312
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
107-18
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Visualization of the stop of microtubule depolymerization that occurs at the high-density region of microtubule-associated protein 2 (MAP2).
pubmed:affiliation
Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't