Linked Life Data

3350209

Source:http://linkedlifedata.com/resource/pubmed/id/3350209

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1988-4-25
pubmed:abstractText
During mouse oocyte maturation the regulation of the activity of a cytoplasmic maturation-promoting factor (MPF) was examined. The mouse MPF activity was determined based on its ability to induce maturation in immature starfish oocytes after microinjection with the cytoplasm from mouse oocytes. MPF appeared initially at germinal vesicle breakdown (GVBD), and its activity fluctuated in exact correspondence with meiotic cycles, reaching a peak at each metaphase and almost disappearing at the time of emission of the first polar body. Cycloheximide affected neither the initial MPF appearance nor GVBD. Thereafter, however, in the presence of cycloheximide the meiotic spindle was not formed and MPF disappeared, although the chromosomes remained condensed. After removing cycloheximide, MPF reappeared and was followed by the first metaphase and subsequently by polar body emission. Finally the meiotic cycle progressed to the second metaphase. Thus, for the appearance of MPF, there is a critical period shortly before the first metaphase, after which protein synthesis is required. In the presence of either cytochalasin D or colcemid, MPF activity remained at elevated levels. Addition of cycloheximide to such cytochalasin-treated oocytes, in which the meiotic cycle was arrested at the first metaphase, caused the MPF levels to decrease and was followed by movement of chromosomes to both poles where they decondensed and two nucleus-like structures were formed. Thus, the disappearance of MPF may initiate the metaphase-anaphase transition. Furthermore, detailed cytological examination revealed that chromosomes in cytochalasin-treated oocytes were monovalent while those treated only with cycloheximide were divalent, suggesting that dissociation of the synapsis is a prerequisite for chromosome decondensation after the disappearance of MPF. In all these respects, MPF seems to be a metaphase-promoting factor rather than just a maturation-promoting factor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0012-1606
pubmed:author
pubmed:issnType
Print
pubmed:volume
126
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
242-52
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Regulation of meiotic metaphase by a cytoplasmic maturation-promoting factor during mouse oocyte maturation.
pubmed:affiliation
Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't