Locking the genome: nuclear organization and cell fate

Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland.
Current opinion in genetics & development (Impact Factor: 8.57). 02/2011; 21(2):167-74. DOI: 10.1016/j.gde.2011.01.023
Source: PubMed

ABSTRACT The differentiation of pluripotent or totipotent cells into various differentiated cell types is accompanied by a restriction of gene expression patterns, alteration in histone and DNA methylation, and changes in the gross nuclear organization of eu- and heterochromatic domains. Several recent studies have coupled genome-wide mapping of histone modifications with changes in gene expression. Other studies have examined changes in the subnuclear positioning of tissue-specific genes upon transcriptional induction or repression. Here we summarize intriguing correlations of the three phenomena, which suggest that in some cases causal relationships may exist.

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Available from: Peter Meister, Jul 28, 2015
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    • "However, we note that the expanded HS­ induced array did not shift inwards, but rather unfolded along the inner NE (Fig. 1 D). Gene induction and array deconden­ sation were correlated, as both were ablated in a temperature­ sensitive hsf-1 mutant (hsf-1(sy441); Hajdu­Cronin et al., 2004; Figs. 1 F and S1 B). induction or shift to the nuclear lamina upon tissue­specific repression (for review see Meister et al., 2011). In mammalian cultured cells, the heat shock (HS) gene Hsp70 localized prefer­ entially to internal nuclear speckles upon activation (Hu et al., 2010), whereas the Hsp70 gene in cultured Drosophila Sch­ neider 2 (S2) cells was perinuclear (Kurshakova et al., 2007). "
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    The Journal of Cell Biology 03/2013; 200(5):589-604. DOI:10.1083/jcb.201207024 · 9.69 Impact Factor
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    • "Eukaryotic genomic DNA is folded with histone and nonhistone proteins into chromatin, which is then arranged into complex higher-order structures to achieve the level of compaction needed to fit the entire genome into the nucleus. It is increasingly recognized that spatial and temporal genome organization is essential for gene expression, DNA replication, and maintenance of genome stability (Misteli, 2007; Mekhail and Moazed, 2010; Meister et al., 2011; Rajapakse and Groudine, 2011). One of the most striking examples of genome organization is the Rabl-like configuration of chromosomes in the interphase nuclei, in which centromeres are clustered at the nuclear periphery. "
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    The Journal of Cell Biology 11/2012; 199(5). DOI:10.1083/jcb.201208001 · 9.69 Impact Factor
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    • "Currently, three distinct types of transcriptionally inactive heterochromatin domains are described: 1) Domains associated with centromeres and marked by DNA methylation, H3K9me3, H3K20me3 and α/β/γ HP1 ιsoforms; 2) Chromatin associated with nuclear lamina via Lamina-associated domains that enriched by H3K9me2 and HP1α/β; 3) Chromatin marked by H3K27me3 and Polycomb group proteins (Meister et al., 2011; Probst and Almouzni, 2011). Although all three types of heterochromatin domains contain actively transcribed genes, transcription of the majority of genes associated with these domains is repressed either constitutively (at the centromere regions) or temporarily in the developmentally-regulated or context-dependent manners (lamina-associated and Polycombrepressed genes) (Meister et al., 2011). "
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