Linked Life Data

15938636

Source:http://linkedlifedata.com/resource/pubmed/id/15938636

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2005-6-7
pubmed:abstractText
Iron regulatory proteins (IRPs) regulate iron metabolism in mammalian cells. We used biophysical techniques to examine the solution properties of apo-IRP1 and apo-IRP2 and the interaction with their RNA ligand, the iron regulatory element (IRE). Sedimentation velocity and equilibrium experiments have shown that apo-IRP1 exists as an equilibrium mixture of monomers and dimers in solution, with an equilibrium dissociation constant in the low micromolar range and slow kinetic exchange between the two forms. However, only monomeric IRP1 is observed in complex with IRE. In contrast, IRP2 exists as monomer in both the apo-IRP2 form and in the IRP2/IRE complex. For both IRPs, sedimentation velocity and dynamic light-scattering experiments show a decrease of the Stokes radius upon binding of IRE. This conformational change was also observed by circular dichroism. Studies with an RNA molecule complementary to IRE indicate that, although specific base interactions can increase the stability of the protein/RNA complex, they are not essential for inducing this conformational change. The dynamic change of the IRP between different oligomeric and conformational states induced by interaction with IRE may play a role in the iron regulatory functions of IRPs.
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
14
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8470-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15938636-Apoproteins, pubmed-meshheading:15938636-Centrifugation, Density Gradient, pubmed-meshheading:15938636-Circular Dichroism, pubmed-meshheading:15938636-Dimerization, pubmed-meshheading:15938636-Humans, pubmed-meshheading:15938636-Iron Regulatory Protein 1, pubmed-meshheading:15938636-Iron Regulatory Protein 2, pubmed-meshheading:15938636-Ligands, pubmed-meshheading:15938636-Light, pubmed-meshheading:15938636-Pichia, pubmed-meshheading:15938636-Picolines, pubmed-meshheading:15938636-Protein Binding, pubmed-meshheading:15938636-Protein Conformation, pubmed-meshheading:15938636-Protein Structure, Secondary, pubmed-meshheading:15938636-Recombinant Proteins, pubmed-meshheading:15938636-Response Elements, pubmed-meshheading:15938636-Scattering, Radiation, pubmed-meshheading:15938636-Solutions
pubmed:year
2005
pubmed:articleTitle
Self-association and ligand-induced conformational changes of iron regulatory proteins 1 and 2.
pubmed:affiliation
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-5766, USA.
pubmed:publicationType
Journal Article, Comparative Study