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Methylation in fertilised and parthenogenetic preimplantation mouse embryos

Published online by Cambridge University Press:  26 September 2008

S Croteau*
Affiliation:
Laboratoire de Biologie Appliquée, INSA, Villeurbanne, France
Y Menezo
Affiliation:
Laboratoire de Biologie Appliquée, INSA, Villeurbanne, France
*
S. Croteau, Laboratoire de Biologie Appliquée, INSA, bat. 406, 20, Auenue A. Einstein, F-69621 Villeurbanne Cedex, France. Telephone: 33 72 43 83 56. Fax: 33 72 43 85 34.

Summary

DNA methylation is one of the proposed biochemical mechanisms involved in cell differentiation and in genomic imprinting, and DNA methyltransferase (DMT) is a key enzyme in the embryo since mutation of its gene is lethal early in development. In order to verify that non-viability of uniparental embryos was not due to a defect in the regulation of DMT activity, we compared the metabolism of methylation in parthenogenetic embryos (maternal genome) and in fertilised embryos (maternal and paternal genomes). As regards total methylation, estimated by a measure of S-adenosyl methionine (SAM) and S-adenosyl homocysteine (SAH) formation, no significant difference was found between the two kinds of embryos during preimplantation development. Mean values were 4.5 ± 0.6 fmol (SAM +SAH)/h per 2-cell embryo and 0.40 ± 0.05 fmol SAH/h per 2-cell embryo, i.e. a SAH/(SAM + SAH) ratio of 9%; there was no detectable SAH formation in blastocysts. The same observation can be made for DMT activity, with mean values of: 7.8 fmol/h per oocyte, 8.5 fmol/h per 2-cell embryo, 6.1 fmol/h per 4-cell embryo, 4.1 fmol/h per morula, and no detectable activity in blastocysts. Total methylation as well as DNA methylation is characterised by a progressive drop in activity during preimplantation development.

Type
Commentary
Copyright
Copyright © Cambridge University Press 1994

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References

Carlson, L.L., Page, A.W. & Bestor, T.H. (1992). Properties and localization of DNA methyltransferase in preimplantation mouse embryos: implications for genomic imprinting. Genes Dev. 6, 2536–41.CrossRefGoogle ScholarPubMed
Chomet, P.S. (1991). Cytosine methylation in gene silencing mechanisms. C.O. Cell Biol. 3, 438–43.CrossRefGoogle ScholarPubMed
Guerin, P., Gharib, A. & Menezo, Y. (1991). Synthesis of S-adenosyl methionine/S-adenosyl homocysteine in human and bovine ejaculated spermatoza. Mol.Androl. 3, 917.Google Scholar
Howlett, S.K. (1991). Genomic imprinting and nuclear totipotency during embryonic developement. Int. Rev. Cytol. 127, 175–92.CrossRefGoogle Scholar
Howlett, S.K. & Reik, W. (1991). Methylation levels of maternal and paternal genomes during preimplantation development. Development 113, 119–27.CrossRefGoogle ScholarPubMed
Jost, J.P. (1993). Nuclear extracts of chicken embryos promote an active demethylation of DNA by excision repair of 5-methyldeoxytidine. Proc. Natl. Acad. Sci. USA 90, 4684–8.CrossRefGoogle Scholar
Jung, T. (1989). Protein synthesis and degradation in non-cultred and in vitro cultured blastocysts. J. Reprod. Fertil. 86, 507–12.CrossRefGoogle Scholar
Kafri, T., Ariel, M., Brandeis, M., Shemer, R., Urven, L., McCarrey, J., Cedar, H. & Razin, A. (1992). Developmental pattern of gene-specific DNA methylation in the mouse embryo and germ line Genes Dev. 6, 705–14.CrossRefGoogle ScholarPubMed
Kaufman, M.H. (1982).The chromosome complement of single-pronuclear haploid mouse embryo following activation by ethanol treatment. J. Embryol. Exp. Morphol. 71, 139–54.Google ScholarPubMed
Kaufman, M.H, Barton, S.C. & Surani, M.A.H. (1977). Normal postimplantation development of mouse parthenogenetic embryos to the forelimb bud stage. Nature 265, 53–5.CrossRefGoogle Scholar
Lewis, J.D. & Bird, A.P. (1991). DNA methylation and chromatin structure. FEBS Lett. 285, 155–9.CrossRefGoogle ScholarPubMed
Li, E., Bestor, T.H. & Jaenisch, R. (1992). Targeted mutation of the DNA methyltransferase gene results in embryonic lethality. Cell 69, 915–26.CrossRefGoogle ScholarPubMed
Marcus, G.J. (1990). Activation of cumulus-free mouse oocytes. Mol. Reprod. Dev. 26, 159–62.CrossRefGoogle ScholarPubMed
Menezo, Y. & Khatchadourian, C. (1991). The laboratory culture media. Assisted Reprod. Rev. 1, 136–42.Google Scholar
Menezo, Y., Khatchadourian, C., Gharib, A., Hamidi, J., Greenland, T. & Sarda, N. (1989). Regulation of S-adenosyl methionine synthesis in the mouse embryo. Life Sci. 44, 1601–9.CrossRefGoogle ScholarPubMed
Monk, M. (1988). Genomic imprinting. Genes Dev. 2, 921–5.CrossRefGoogle ScholarPubMed
Monk, M., Boubelik, M. & Lehnert, S. (1987). Temporal and regional changes in DNA methylation in the embryonic, extraembryonic and germ cell lineages during mouse embryo development. Development 99, 371–82CrossRefGoogle ScholarPubMed
Monk, M., Adams, R.L.P. & Rinaldi, A. (1991). Decrease in DNA methylase activity during preimplantation development in the mouse. Development 112, 189–92.CrossRefGoogle ScholarPubMed
Piko, L. & Clegg, K.B. (1982). Quantitative changes in total RNA, total poly(A), and ribosomes in early mouse embryos. Dev. Biol. 89, 362–78.CrossRefGoogle ScholarPubMed
Razin, A., Szyf, M., Kafri, T., Roll, M., Giloh, H., Scarpa, S., Carotti, D. & Cantoni, G.L. (1986). Replacement of 5-methylcytosine by cytosine: a possible mechanism for transient DNA demethylation during differentiation. Proc. Natl. Acad. Sci. USA 83, 2827–31.CrossRefGoogle ScholarPubMed
Smith, S.S., Kaplan, B.E., Sowers, L.C. & Newman, E.M. (1992). Machanism of human methyl-directed DNA methyltransferase and the fidelity of cytosine methylation. Proc. Natl. Acad. Sci. USA 89, 4744–8.CrossRefGoogle Scholar
Swann, K. (1990). A cytosolic sperm factor stimulates repetitive calcium increases and mimics fertilization in hamster eggs. Development 110, 1295–302.CrossRefGoogle ScholarPubMed
Whittingham, D.G. & Wales, R.G. (1969). Storage of two-cell mouse embryo in virto. J. Biol. Sci. 22, 1065–68.Google Scholar