Linked Life Data

17634984

Source:http://linkedlifedata.com/resource/pubmed/id/17634984

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-1-2
pubmed:abstractText
Ssn6, a tetratricopeptide repeat (TPR) containing protein, associates with the Tup1 repressor to form a global transcriptional co-repressor complex, which is conserved across species. The three N-terminal TPR repeats of Ssn6, out of a total of 10, are involved in this particular interaction. Our previously reported 3D-modeling and mutagenesis data suggested that the structural integrity of TPR1 and its correct positioning relatively to TPR2 are crucial for Tup1 binding. In this study, we first investigate the structural stability of the Tup1 binding domain of Ssn6, in pure form, through a combination of CD spectroscopy and limited proteolysis mapping. The obtained data were next combined with molecular dynamics simulations and disorder/order predictions. This combined study revealed that, although competent to fold, in the absence of Tup1, TPR1 is partially unfolded with its helix B being highly dynamic exposing an apolar surface to the solvent. Subsequent CD spectroscopy on this domain complexed with a Tup1 fragment comprising its Ssn6 binding region provided strong evidence for a conformational change consisting of acquisition of alpha-helical structure with simultaneous stabilization of a coiled-coil configuration upon complex formation. We propose that this conformational change occurs largely in the TPR1 of Ssn6 and is in accord with the concept of folding coupled to binding, proposed for other TPR domains. A possible implication of the structural flexibility of Ssn6 TPR1 in Tup1 recognition is discussed and a novel mode of interaction is proposed for this particular TPR-mediated complex.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1097-0134
pubmed:author
pubmed:copyrightInfo
(c) 2007 Wiley-Liss, Inc.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
72-82
pubmed:dateRevised
2009-7-23
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Investigating the structural stability of the Tup1-interaction domain of Ssn6: evidence for a conformational change on the complex.
pubmed:affiliation
Institute of Biology, National Centre for Scientific Research Demokritos, 15310 Ag. Paraskevi Attikis, Greece.
pubmed:publicationType
Journal Article