Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1991-11-25
pubmed:abstractText
Repeated motifs, rich in basic residues, are characteristic of both the N-terminal domain of the nucleolus-specific protein, nucleolin, and the second half of the C-terminal domain of histone H1. These repeats are also the target for phosphorylation by the mitosis-specific p34cdc2 kinase. We have previously shown that synthetic peptides [(KTPKKAKKP)2 for histone H1 and (ATPAKKAA)2 for nucleolin] corresponding to these two repeated motifs are able to act in synergy to induce DNA hypercondensation (Erard et al., 1990). In order to determine the molecular basis of this synergistic interaction, we have studied the condensation of the homopolymer poly(dA).poly(dT) in the presence of the two synthetic peptides. Circular dichroism has been used to monitor the psi (+)-type condensation and has revealed that phosphorylation enhances the synergistic effect of the two peptides. Analysis of different combinations of the two peptides suggests that there is a direct interaction between them which is stabilized by phosphorylation. Furthermore, there is a striking correlation between the degree of homopolymer condensation and the stability of the heteromeric complex. Phosphorylation takes place on the threonine residues on the repeat motifs within a region which is likely to adopt a beta-turn structure. Circular dichroism and infrared spectroscopy provide evidence that phosphorylation stabilizes the beta-turn structure of both peptides, and computer modeling shows that this may be due to steric hindrance imposed by the phosphate group. We suggest that phosphorylated nucleolin and histone H1 interact through their homologous domain structured in beta-spirals in order to condense certain forms of DNA during mitosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10329-36
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:1931957-Amino Acid Sequence, pubmed-meshheading:1931957-Animals, pubmed-meshheading:1931957-Chromatin, pubmed-meshheading:1931957-Drug Stability, pubmed-meshheading:1931957-Drug Synergism, pubmed-meshheading:1931957-Histones, pubmed-meshheading:1931957-Mitosis, pubmed-meshheading:1931957-Models, Molecular, pubmed-meshheading:1931957-Molecular Sequence Data, pubmed-meshheading:1931957-Nuclear Proteins, pubmed-meshheading:1931957-Peptides, pubmed-meshheading:1931957-Phosphoproteins, pubmed-meshheading:1931957-Phosphorylation, pubmed-meshheading:1931957-Poly dA-dT, pubmed-meshheading:1931957-Protein Conformation, pubmed-meshheading:1931957-Protein Kinases, pubmed-meshheading:1931957-RNA-Binding Proteins, pubmed-meshheading:1931957-Software, pubmed-meshheading:1931957-Starfish
pubmed:year
1991
pubmed:articleTitle
Synergistic effect of histone H1 and nucleolin on chromatin condensation in mitosis: role of a phosphorylated heteromer.
pubmed:affiliation
Centre de Recherche de Biochimie et de Génétique Cellulaires, Centre National de la Recherche Scientifique, Toulouse, France.
pubmed:publicationType
Journal Article