title: A novel role for DNA methyltransferase 1 in regulating oocyte cytoplasmic maturation in pigs.
abstract: Maternal factors are required for oocyte maturation and embryo development. To better understand the role of DNA methyltransferase 1 (Dnmt1) in oocyte maturation and embryo development, small interfering RNA (siRNA) was conducted in porcine oocytes. In this study, our results showed that Dnmt1 localized in oocyte cytoplasm and its expression displayed no obvious change during oocyte maturation. When siRNAs targeting Dnmt1 were injected into germinal vesicle (GV) stage oocytes, Dnmt1 transcripts significantly decreased in matured oocytes (P<0.05). After Dnmt1 knockdown in GV stage oocytes, the significant reduction of glutathione content, mitochondrial DNA copy number, glucose-6-phosphate dehydrogenase activity and expression profiles of maternal factors and the severely disrupted distribution of cortical granules were observed in MII stage oocytes (P<0.05), leading to the impaired oocyte cytoplasm. Further study displayed that Dnmt1 knockdown in GV stage oocytes significantly reduced the development of early embryos generated through parthenogenetic activation, in vitro fertilization and somatic cell nuclear transfer (P<0.05). In conclusion, Dnmt1 was indispensable for oocyte cytoplasmic maturation, providing a novel role for Dnmt1 in the regulation of oocyte maturation.
authors.affiliation: College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China; Dairy Cattle Research Center, Shandong Academy of Agricultural Sciences, Jinan, Shandong Province, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Huan
authors.affiliation: College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China.
authors.forename: Bingteng
authors.initials: B
authors.lastname: Xie
authors.affiliation: College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China.
authors.forename: Shichao
authors.initials: S
authors.lastname: Liu
authors.affiliation: College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China.
authors.forename: Qingran
authors.initials: Q
authors.lastname: Kong
authors.affiliation: College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation; D003593:Cytoplasm / Q000201:enzymology*; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D004272:DNA, Mitochondrial / Q000235:genetics; D005260:Female; D005307:Fertilization in Vitro; D018628:Gene Dosage; D055785:Gene Knockdown Techniques; D005978:Glutathione / Q000378:metabolism; D007267:Injections; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology* / Q000201:enzymology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D034421:Sus scrofa
chemical_list: D004272:DNA, Mitochondrial; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; D005978:Glutathione