Meiotic competence and acetylation pattern of UV light classified mouse antral oocytes after meiotic arrest with isobutylmethylxanthine.
Chromatin transformation from a diffused or NSN configuration to a compacted or SN shape that forms a ring around the nucleolus is regarded as one of the modifications necessary for successful embryonic development. But the process of the transformation is poorly understood. In this study we cultured mouse antral oocytes under meiotic arrest with IBMX for periods between 3 and 24 hr. We observed the chromatin status of the oocytes before and after culture under UV illumination. We reported here that the NSN configured oocytes transformed temporally through an intermediate form into the SN configuration while under meiotic arrest in vitro. Meiotic rate was improved in the NSN oocytes after the meiotic arrest but decreased in the SN oocytes. We also reported that chromatin of both the NSN and SN oocytes was acetylated and the two groups underwent the same pattern of H4/K5 deacetylation during meiotic maturation. We hypothesized that the transformation of mouse oocyte from the NSN to SN type may be time rather than oocyte size specific and the abrupt deacetylation of NSN oocyte during spontaneous maturation may explain its poor meiotic and developmental competence.
Ola
Safiriyu Idowu
SI
State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
Wang
Qiang
Q
Ai
Jun-Shu
JS
Yin
Shen
S
Liang
Cheng-Guang
CG
Chen
Da-Yuan
DY
Sun
Qing-Yuan
QY
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology*; D000107:Acetylation; D000818:Animals; D048429:Cell Size / Q000187:drug effects; D002478:Cells, Cultured; D002843:Chromatin / Q000502:physiology; D005260:Female; D006657:Histones / Q000378:metabolism; D008540:Meiosis / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008856:Microscopy, Fluorescence; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D014466:Ultraviolet Rays
D002843:Chromatin; D006657:Histones; D015056:1-Methyl-3-isobutylxanthine