A novel role for DNA methyltransferase 1 in regulating oocyte cytoplasmic maturation in pigs

Yanjun Huan; Bingteng Xie; Shichao Liu; Qingran Kong; Zhonghua Liu

doi:10.1371/journal.pone.0127512

A novel role for DNA methyltransferase 1 in regulating oocyte cytoplasmic maturation in pigs

PLoS One. 2015 May 26;10(5):e0127512. doi: 10.1371/journal.pone.0127512. eCollection 2015.

Authors

Yanjun Huan¹, Bingteng Xie², Shichao Liu², Qingran Kong², Zhonghua Liu²

Affiliations

¹ College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China; Dairy Cattle Research Center, Shandong Academy of Agricultural Sciences, Jinan, Shandong Province, China.
² College of Life Science, Northeast Agricultural University, Harbin, Heilongjiang Province, China.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Blastocyst / cytology
Blastocyst / metabolism
Cell Differentiation
Cytoplasm / enzymology*
DNA (Cytosine-5-)-Methyltransferase 1
DNA (Cytosine-5-)-Methyltransferases / metabolism*
DNA, Mitochondrial / genetics
Female
Fertilization in Vitro
Gene Dosage
Gene Knockdown Techniques
Glutathione / metabolism
Injections
Nuclear Transfer Techniques
Oocytes / cytology*
Oocytes / enzymology*
RNA, Messenger / genetics
RNA, Messenger / metabolism
RNA, Small Interfering / metabolism
Sus scrofa

Substances

DNA, Mitochondrial
RNA, Messenger
RNA, Small Interfering
DNA (Cytosine-5-)-Methyltransferase 1
DNA (Cytosine-5-)-Methyltransferases
Glutathione

Grants and funding

National Basic Research Program of China, Program 973 (2011CB944202) to ZHL, http://www.most.gov.cn/; National Natural Science Foundation of China, NSFC (31101035) to ZHL, http://www.nsfc.gov.cn/; China Postdoctoral Science Foundation (2014M551943) to YJH, http://bg.chinapostdoctor.org.cn/; the special foundation of Postdoctoral Innovation Project in Shandong Province of China (201402044) to YJH, http://www.sdhrss.gov.cn/cm/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.