Dynamics of Dnmt1 methyltransferase expression and intracellular localization during oogenesis and preimplantation development.

@article{Ratnam2002DynamicsOD,
  title={Dynamics of Dnmt1 methyltransferase expression and intracellular localization during oogenesis and preimplantation development.},
  author={Sarayu Ratnam and C. Mertineit and F. Ding and C. Howell and H. Clarke and T. Bestor and J. Chaillet and J. Trasler},
  journal={Developmental biology},
  year={2002},
  volume={245 2},
  pages={
          304-14
        }
}
The imprinting of mammalian genes depends on the maintenance of DNA methylation patterns during pre- and postimplantation development. Dnmt1o is a variant form of the somatically expressed Dnmt1 cytosine methyltransferase that is synthesized and stored in the oocyte cytoplasm and trafficks to the eight-cell nucleus during preimplantation development, where it maintains DNA methylation patterns on alleles of imprinted genes. Transcripts encoding Dnmt1 are present in preimplantation embryos… Expand
Maintenance of genomic methylation patterns during preimplantation development requires the somatic form of DNA methyltransferase 1.
TLDR
It is demonstrated that the somatic form of DnMT1 (Dnmt1s) is present in association with chromatin in MII-stage oocytes as well as in the nucleus throughout preimplantation development and is responsible for the maintenance methylation of particular genomic regions whose methylation patterns must be faithfully maintained during preim implantation development. Expand
Coordinate regulation of DNA methyltransferase expression during oogenesis
TLDR
The results indicate that these enzymes are coordinately regulated and that their expression peaks during the stage of postnatal oocyte development when maternal methylation imprints are established, and demonstrate that the involvement of DNMT3L in retrotransposon silencing is restricted to the male germ line. Expand
Preimplantation expression of the somatic form of Dnmt1 suggests a role in the inheritance of genomic imprints
TLDR
It is suggested that Dnmt1s provides maintenance methyltransferase activity for the inheritance of methylation imprints in the early mouse embryo and the developmental source is the critical determinant of DnMT1 function during preimplantation development. Expand
Species‐dependent expression patterns of DNA methyltransferase genes in mammalian oocytes and preimplantation embryos
TLDR
Species‐dependent differences as well as similarities in expression patterns of DNMT genes among mammals are described, and the results are compared with expression profiles in the mouse and other mammalian species. Expand
Localization of DNA methyltransferase-1 during oocyte differentiation, in vitro maturation and early embryonic development in cow
TLDR
Data indicate that while Dnmt1 is retained in the cytoplasm in metaphase II stage oocytes and zygotes, it enters the nuclei of 8–16 cell stage embryos, as suggested in mouse. Expand
Dynamic regulation of DNA methyltransferases in human oocytes and preimplantation embryos after assisted reproductive technologies.
TLDR
The existence of species differences for mammalian DNA methylation enzymes is confirmed and the spatial and temporal expression patterns of DNMTs seem to be disturbed in abnormally developing embryos and in embryos that have been cryopreserved. Expand
Maternal and zygotic Dnmt1 are necessary and sufficient for the maintenance of DNA methylation imprints during preimplantation development.
TLDR
It is demonstrated, by using conditional knockout mice, that the other known DNA methyltransferases Dnmt3a and DnMT3b are dispensable for the maintenance of the methylation marks at most imprinted loci and that zygotic DNmt1 is expressed in the preimplantation embryo. Expand
DNA methyltransferase 1o functions during preimplantation development to preclude a profound level of epigenetic variation.
TLDR
The results suggest that loss of DNMT1o in just one cell cycle is responsible for the extensive variation in the epigenotypes in both embryos and their associated extraembryonic tissues. Expand
In vivo stabilization of the Dnmt1 (cytosine-5)- methyltransferase protein
  • F. Ding, J. Chaillet
  • Biology, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 2002
TLDR
The intrinsic stability of the Dnmt1o protein is the most likely reason for its use as a maternal-effect protein; stable ooplasmic stores of DnMT1o would be available to traffick into the nuclei of the eight-cell stage embryo and maintain methylation patterns on alleles of imprinted genes during the fourth embryonic S phase. Expand
Analysis of DNA (cytosine 5) methyltransferase mRNA sequence and expression in bovine preimplantation embryos, fetal and adult tissues.
TLDR
Results of Real Time PCR analysis indicate significant differences in Dnmt mRNA expression levels exist among different tissue types as well as between fetal and adult stages and regarding the implication of abnormal DNMT expression in cloned embryos. Expand
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