Article

Histone Variants in Metazoan Development

Laboratory of Chromatin Biology and Epigenetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
Developmental Cell (Impact Factor: 10.37). 11/2010; 19(5):662-74. DOI: 10.1016/j.devcel.2010.10.014
Source: PubMed

ABSTRACT Embryonic development is regulated by both genetic and epigenetic mechanisms, with nearly all DNA-templated processes influenced by chromatin architecture. Sequence variations in histone proteins, core components of chromatin, provide a means to generate diversity in the chromatin structure, resulting in distinct and profound biological outcomes in the developing embryo. Emerging literature suggests that epigenetic contributions from histone variants play key roles in a number of developmental processes such as the initiation and maintenance of pericentric heterochromatin, X-inactivation, and germ cell differentiation. Here, we review the role of histone variants in the embryo with particular emphasis on early mammalian development.

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Available from: Peter W Lewis, Sep 14, 2014
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    • "The transition to the first mitosis at the onset of pre-implantation embryo development is a unique and highly dynamic process, taking place in the absence of major transcriptional activity. The extensive chromatin remodeling of paternal and maternal genomes in the one cell zygote is quickly followed by active global DNA de-methylation of the paternal genome and results in the establishment of epigenetic asymmetry in which paternal and maternal pronuclei acquire a unique epigenetic landscape characterized by distinct DNA and histone methylation marks, and histone variants (Mayer et al., 2000b; Oswald et al., 2000; Santos et al., 2005; Santenard and Torres-Padilla, 2009; Banaszynski et al., 2010; Kota and Feil, 2010). Remarkably, epigenetic asymmetry is maintained during interphase in the two-cell embryo where distinct chromatin marks reveal the polar distribution of paternal and maternal genomes (Mayer et al., 2000a; Hayashi- Takanaka et al., 2011). "
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    • "The chromosomes separate with half being extruded into the first polar body and the egg arrests once again, at metaphase II, until fertilisation (Holt et al., 2013; Jones et al., 2013). Following this event, the second polar body is extruded and the male and female pronuclei fuse to generate a zygote (Banaszynski et al., 2010). "
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    • "Chromatin remodeling and histone modifications have been implicated in regulating ESC differentiation or cellular reprogramming (Orkin and Hochedlinger, 2011). However, the role of another important aspect of chromatin biology, the incorporation of histone variants, is relatively unknown (Banaszynski et al., 2010). Histone variant proteins, which carry notable differences in primary amino acid sequences, are often expressed at low levels in comparison to the major histone isoforms (Banaszynski et al., 2010). "
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