Linked Life Data

10654080

Source:http://linkedlifedata.com/resource/pubmed/id/10654080

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2000-3-14
pubmed:abstractText
Mechanisms of chromosome condensation and segregation during the first meiotic division are not well understood. Resolution of recombination events to form chiasmata is important, for it is chiasmata that hold homologous chromosomes together for their oppositional orientation on the meiotic metaphase spindle, thus ensuring their accurate segregation during anaphase I. Events at the centromere are also important in bringing about proper attachment to the spindle apparatus. This study was designed to correlate the presence and activity of two proteins at the centromeric heterochromatin, topoisomerase II alpha (TOP2A) and histone H3, with the processes of chromosome condensation and individualization of chiasmate bivalents in murine spermatocytes. We tested the hypothesis that phosphorylation of histone H3 is a key event instigating localization of TOP2A to the centromeric heterochromatin and condensation of chromosomes as spermatocytes exit prophase and progress to metaphase. Activity of topoisomerase II is required for condensation of chromatin at the end of meiotic prophase. Histone H3 becomes phosphorylated at the end of prophase, beginning with its phosphorylation at the centromeric heterochromatin in the diplotene stage. However, it cannot be involved in localization of TOP2A, since TOP2A is localized to the centromeric heterochromatin throughout most of meiotic prophase. This observation suggests a meiotic function for TOP2A in addition to its role in chromatin condensation. The use of kinase inhibitors demonstrates that phosphorylation of histone H3 can be uncoupled from meiotic chromosome condensation; therefore other proteins, such as those constituting metaphase-promoting factor, must be involved. These results define the timing of important meiotic events at the centromeric heterochromatin and provide insight into mechanisms of chromosome condensation for meiotic metaphase.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0009-5915
pubmed:author
pubmed:issnType
Print
pubmed:volume
108
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
412-25
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:10654080-Animals, pubmed-meshheading:10654080-Antigens, Neoplasm, pubmed-meshheading:10654080-Centromere, pubmed-meshheading:10654080-Chromosomes, pubmed-meshheading:10654080-DNA Topoisomerases, Type II, pubmed-meshheading:10654080-DNA-Binding Proteins, pubmed-meshheading:10654080-Fluorescent Antibody Technique, Indirect, pubmed-meshheading:10654080-Heterochromatin, pubmed-meshheading:10654080-Histones, pubmed-meshheading:10654080-Humans, pubmed-meshheading:10654080-Isoenzymes, pubmed-meshheading:10654080-Male, pubmed-meshheading:10654080-Maturation-Promoting Factor, pubmed-meshheading:10654080-Meiosis, pubmed-meshheading:10654080-Metaphase, pubmed-meshheading:10654080-Mice, pubmed-meshheading:10654080-Mice, Inbred BALB C, pubmed-meshheading:10654080-Mice, Inbred ICR, pubmed-meshheading:10654080-Phosphorylation, pubmed-meshheading:10654080-Spermatocytes, pubmed-meshheading:10654080-Spermatogenesis, pubmed-meshheading:10654080-Testis
pubmed:year
1999
pubmed:articleTitle
Meiotic events at the centromeric heterochromatin: histone H3 phosphorylation, topoisomerase II alpha localization and chromosome condensation.
pubmed:affiliation
Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville 37996, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.