Linked Life Data

17516631

Source:http://linkedlifedata.com/resource/pubmed/id/17516631

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
2007-6-12
pubmed:abstractText
It is widely accepted that a pair of EF-hands is the functional unit of typical four EF-hand proteins such as calmodulin or troponin C. In this work we investigate the structure and stability of the four EF-hand domains in the related protein calcium- and integrin-binding protein 1 (CIB1) in the presence and absence of Mg2+ or Ca2+, to determine if similar EF-hand interactions occur. The backbone structure and flexibility of CIB1 were first studied by NMR spectroscopy, and these studies were complimented with steady-state fluorescence spectroscopy and chemical denaturation experiments using mutant CIB1 proteins having single Trp reporter groups in each of the four EF-hand domains EF-I (F34W), EF-II (F91W), EF-III (L128W), and EF-IV (F173W). We find that Mg2+-CIB1 adopts a well-folded structure similar to Ca2+-CIB1, except for some conformational heterogeneity in the C-terminal EF-IV domain. The structure of apo-CIB1 is significantly more dynamic, especially within EF-II, EF-III, and a partially unfolded EF-IV region, but the N-terminal EF-I region of apo-CIB1 has a well-ordered and more stable structure. The data reveal significant communication between the N- and C-lobes of CIB1, and show that transient intermediate conformations are formed along the unfolding pathway for each form of the protein. Collectively the data demonstrate that the communication between the paired EF-hand domains as well as between the N- and C-lobes of CIB1 is distinct from the ancestral proteins calmodulin and troponin C, which might be important for the unique function of CIB1 in numerous biological processes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7088-98
pubmed:meshHeading
pubmed-meshheading:17516631-Amino Acid Sequence, pubmed-meshheading:17516631-Amino Acid Substitution, pubmed-meshheading:17516631-Calcium, pubmed-meshheading:17516631-Calcium-Binding Proteins, pubmed-meshheading:17516631-Drug Stability, pubmed-meshheading:17516631-Humans, pubmed-meshheading:17516631-Magnesium, pubmed-meshheading:17516631-Models, Molecular, pubmed-meshheading:17516631-Molecular Sequence Data, pubmed-meshheading:17516631-Mutagenesis, Site-Directed, pubmed-meshheading:17516631-Nuclear Magnetic Resonance, Biomolecular, pubmed-meshheading:17516631-Protein Denaturation, pubmed-meshheading:17516631-Protein Folding, pubmed-meshheading:17516631-Protein Structure, Tertiary, pubmed-meshheading:17516631-Recombinant Proteins, pubmed-meshheading:17516631-Spectrometry, Fluorescence, pubmed-meshheading:17516631-Tryptophan
pubmed:year
2007
pubmed:articleTitle
Domain stability and metal-induced folding of calcium- and integrin-binding protein 1.
pubmed:affiliation
Structural Biology Research Group, Department of Biological Sciences, University of Calgary, 2500 University Drive N.W., Calgary, AB, Canada, T2N 1N4.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't