Methylation changes of lysine 9 of histone H3 during preimplantation mouse development.
Immediately after fertilization, a chromatin remodeling process in the oocyte cytoplasm extracts protamine molecules from the sperm-derived DNA and loads histones onto it. We examined how the histone H3-lysine 9 methylation system is established on the remodeled sperm chromatin in mice. We found that the paternal pronucleus was not stained for dimethylated H3-K9 (H3-m2K9) during pronucleus development, while the maternal genome stained intensively. Such H3-m2K9 asymmetry between the parental pronuclei was independent of HP1b localization and, much like DNA methylation, was preserved to the two-cell stage when the nucleus appeared to be compartmentalized for H3-m2K9. A conspicuous increase in H3-m2K9 level was observed at the four-cell stage, and then the level was maintained without a visible change up to the blastocyst stage. The behavior of H3-m2K9 was very similar, but not identical, to that of 5-methylcytosine during preimplantation development, suggesting that there is some connection between methylation of histone and of DNA in early mouse development.
Yeo
Seungeun
S
Laboratory of Development and Differentiation, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Korea.
Lee
Kyung-Kwang
KK
Han
Yong-Mahn
YM
Kang
Yong-Kook
YK
D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006657:Histones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008239:Lysine / Q000235:genetics*; D008297:Male; D008745:Methylation; D051379:Mice; D008810:Mice, Inbred C57BL; D009865:Oocytes / Q000502:physiology; D013552:Swine; D015053:Zygote / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism
D006657:Histones; D008239:Lysine