Research

Evidence for conserved DNA and histone H3 methylation reprogramming in mouse, bovine and rabbit zygotes

Konstantin Lepikhov¹ , Valeri Zakhartchenko² , Ru Hao² , Feikun Yang² , Christine Wrenzycki³ , Heiner Niemann⁴ , Eckhard Wolf² and Joern Walter¹

¹  University of Saarland, Natural Sciences – Technical Faculty III, Biological Sciences, Genetics/Epigenetics, 66123 Saarbrücken, Germany

²  Department of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilian University, 81377 Munich, Germany

³  University of Veterinary Medicine, Clinic for Cattle, Reproductive Medicine Unit, 30173 Hannover, Germany

⁴  Institute of Animal Breeding (FAL), Department of Biotechnology, Höltystrasse 10, Mariensee, 31535 Neustadt, Germany

author email corresponding author email

Epigenetics & Chromatin 2008, 1:8doi:10.1186/1756-8935-1-8

Published:	3 November 2008

Abstract

Background

In mammals the parental genomes are epigenetically reprogrammed after fertilization. This reprogramming includes a rapid demethylation of the paternal (sperm-derived) chromosomes prior to DNA replication in zygotes. Such active DNA demethylation in the zygote has been documented for several mammalian species, including mouse, rat, pig, human and cow, but questioned to occur in rabbit.

Results

When comparing immunohistochemical patterns of antibodies against 5-methyl-cytosine, H3K4me3 and H3K9me2 modifications we observe similar pronuclear distribution and dynamics in mouse, bovine and rabbit zygotes. In rabbit DNA demethylation of the paternal chromosomes occurs at slightly advanced pronuclear stages. We also show that the rabbit oocyte rapidly demethylates DNA of donor fibroblast after nuclear transfer.

Conclusion

Our data reveal that major events of epigenetic reprogramming during pronuclear maturation, including mechanisms of active DNA demethylation, are apparently conserved among mammalian species.