2013.5.28 DNA methylation regularity of genetic modification from parent to offspring
Jiang LIU
Ph.D., Institute of Biophysics, CAS Principal Investigator, Beijing Institute of Genomics, CAS | |
Time:1:00pm, May. 28, 2013
Address:Rm. 102, Old Chemistry Building, east Wing, 1rd floor, CQB
Abstract:
5-methlcytosine is a major epigenetic modification that is sometimes called "the fifth nucleotide." How-ever, our knowledge of how offspring inherit the DNA methylome from parents is limited. We generated nine single-base resolution DNA methylomes, including zebrafish gametes and early embryos. The oocyte methylome is significantly hypomethy-lated compared to sperm. Strikingly, the paternal DNA methylation pattern is maintained throughout early embryogenesis. The maternal DNA methylation pattern is maintained until the 16-cell stage. Then, the oocyte methylome is gradually discarded through cell division and is progressively reprog-rammed to a pattern similar to that of the sperm methylome. The passive demethylation rateand the de novo methylation rate are similar in the maternal DNA. By the midblastula stage, the embryo's methylome is virtually identical to the sperm methylome. Moreover, inheritance of the sperm methylome facilitates the epigenetic regulation of embryogenesis. Therefore, besides DNA sequences, sperm DNA methylome is also inherited in zebrafish early embryos.
Host:Chao TANG