Linked Life Data

9012668

Source:http://linkedlifedata.com/resource/pubmed/id/9012668

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-2-26
pubmed:abstractText
Homeodomains are a class of DNA-binding protein domains which play an important role in genetic regulation in eukaryotes. We have characterized the thermodynamics of folding and sequence-specific association with DNA of the MAT alpha 2 homeodomain of yeast. Using differential scanning and isothermal titration calorimetry, we measured the enthalpy, heat capacity, and Gibbs free energy changes of these processes. The protein-DNA interaction is enthalpically driven at physiological temperatures. DSC data on the process of melting the protein-DNA complex at different salt concentrations were dissected into its endothermic components, yielding the enthalpy change and dissociation constant of binding. A comparison of the circular dichroism spectra of the free and DNA-bound protein species revealed the formation of additional alpha-helical structure upon binding to DNA. We propose that the latter half of helix 3, the recognition helix, is substantially unfolded in the free protein under the conditions used, as has been observed with other homeodomains [Tsao, D. H. H., et al. (1994) Biochemistry 33, 15053-15060: Cox, M., et al. (1995) J. Biomol. NMR 5, 23-32]. Formation of protein structure is induced by DNA binding, and the energies measured for association therefore include a component due to folding.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
526-35
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Energetics of folding and DNA binding of the MAT alpha 2 homeodomain.
pubmed:affiliation
Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't