Linked Life Data

10852909

Source:http://linkedlifedata.com/resource/pubmed/id/10852909

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
36
pubmed:dateCreated
2000-10-13
pubmed:abstractText
The in vitro Ca(2+) regulation of the actomyosin Mg(2+)-ATPase at physiological ratios of actin, tropomyosin, and troponin occurs only in the presence of troponin T. We have previously demonstrated that a polypeptide corresponding to the first 191 amino acids of troponin T (TnT-(1-191)) activates the actomyosin Mg(2+)-ATPase in the presence of tropomyosin. In order to further characterize this activation domain, we constructed troponin T fragments corresponding to residues 1-157 (TnT-(1-157)), 1-76 (TnT-(1-76)), 77-157 (TnT-(77-157)), 77-191 (TnT-(77-191)), and 158-191 (TnT-(158-191)). Assays using these fragments demonstrated the following: (a) residues 1-76 do not bind to tropomyosin or actin; (b) residues 158-191 bind to actin cooperatively but not to tropomyosin; (c) the sequence 77-157 is necessary for troponin interaction with residue 263 of tropomyosin; (d) TnT-(77-191) on its own activates the actomyosin ATPase activity as described previously for TnT-(1-191). TnT-(1-157), TnT-(1-76), TnT-(77-157), TnT-(158-191), and combinations of TnT-(158-191) with TnT-(1-157) or TnT-(77-157) showed no effect on the ATPase activity. We conclude that the activation of actomyosin ATPase activity is mediated by a direct interaction between amino acids 77 and 191 of troponin T, tropomyosin, and actin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27513-9
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Mapping the domain of troponin T responsible for the activation of actomyosin ATPase activity. Identification of residues involved in binding to actin.
pubmed:affiliation
Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo CP 26.077, CEP 05599-970 São Paulo, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't