Linked Life Data

12890737

Source:http://linkedlifedata.com/resource/pubmed/id/12890737

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2003-10-21
pubmed:abstractText
Early embryonic cleavages are mostly regulated by maternal components then control of development progressively depends on newly synthesized zygotic products. The timing of the first cleavages is a way to assess embryo quality. The goal of this study was to evaluate the duration of the fourth cell cycle, at the time of maternal-to-zygotic transition (MZT) in in vitro-produced bovine embryos by means of cinematographic analysis. We found that 75% of the embryos displayed a long fourth cycle (43.5 +/- 5.4 h) whereas the remaining embryos had a very short fourth cell cycle (8.9 +/- 2.9 h). Both groups did not differ in cleavage rhythm up to the eight-cell stage and timing of cavitation and blastocyst expansion was identical. However, embryos with a short fourth cell cycle had a better blastocyst rate than embryos with a long cycle (59% versus 38%, P < 0.01). Total cell number, inner cell mass (ICM):total cell ratio, and hatching rate were identical for blastocysts produced from embryos with either a long or a short fourth cell cycle. In a second experiment, we showed that increasing the oxygen tension, from 5% to 20%, decreased the percentage of embryos with a short fourth cell cycle, from 25% to 11% (P < 0.01), indicating that suboptimal culture conditions can influence the length of this cycle. Finally, we investigated whether fourth cell cycle duration could be influenced by transcription inhibition. With alpha-amanitin added at 18 h postinsemination (HPI), cleavage was reduced (66% versus 79%) and, at 70 HPI, the 9- to 16-cell rate increased (50% versus 25%) concomitantly with a 5- to 8-cell rate decrease (16% versus 47%). A similar pattern was observed when the drug was added at 6 HPI or 42 HPI but not at 0 HPI. Cinematographic analysis revealed that alpha-amanitin increased the first cell cycle duration whereas the second and third cell cycles were not affected. With the drug, one third of the embryos could develop up to the 9- to 16-cell stage and they all had a short fourth cell cycle (11.2 +/- 3.7 h) with a good synchrony of cleavage between blastomeres. These results suggest that duration of the fourth cell cycle of bovine embryo, during the MZT, is under a zygotic transcriptional control that can be affected by oxidative conditions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1707-13
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:12890737-Amanitins, pubmed-meshheading:12890737-Animals, pubmed-meshheading:12890737-Cattle, pubmed-meshheading:12890737-Cell Count, pubmed-meshheading:12890737-Cell Cycle, pubmed-meshheading:12890737-Cell Nucleus, pubmed-meshheading:12890737-Embryo, Mammalian, pubmed-meshheading:12890737-Embryonic and Fetal Development, pubmed-meshheading:12890737-Female, pubmed-meshheading:12890737-Fertilization in Vitro, pubmed-meshheading:12890737-Hyperoxia, pubmed-meshheading:12890737-Microscopy, Video, pubmed-meshheading:12890737-Nucleic Acid Synthesis Inhibitors, pubmed-meshheading:12890737-Oxygen, pubmed-meshheading:12890737-Pregnancy, pubmed-meshheading:12890737-RNA Polymerase II, pubmed-meshheading:12890737-Reactive Oxygen Species, pubmed-meshheading:12890737-Transcription, Genetic, pubmed-meshheading:12890737-Zygote
pubmed:year
2003
pubmed:articleTitle
Cell cycle duration at the time of maternal zygotic transition for in vitro produced bovine embryos: effect of oxygen tension and transcription inhibition.
pubmed:affiliation
Unité Vétérinaire, Institut des Sciences de la Vie, Université Catholique de Louvain, Louvain-la-Neuve B-1348, Belgium. Lequarre@vete.ucl.ac.be
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't