Tyler, J. K. et al. The RCAF complex mediates chromatin assembly during DNA replication and repair. Nature 402, 555- 560

Department of Biology and Center for Molecular Genetics, University of California at San Diego, La Jolla 92093-0347, USA.
Nature (Impact Factor: 42.35). 12/1999; 402(6761):555-560. DOI: 10.1038/990147

ABSTRACT Chromatin assembly is a fundamental biological process that is essential for the replication and maintenance of the eukaryotic genome. In dividing cells, newly synthesized DNA is rapidly assembled into chromatin by the deposition of a tetramer of the histone proteins H3 and H4, followed by the deposition of two dimers of histones H2A and H2B to complete the nucleosome the fundamental repeating unit of chromatin. Here we describe the identification, purification, cloning, and characterization of replication- coupling assembly factor (RCAF), a novel protein complex that facilitates the assembly of nucleosomes onto newly replicated DNA in vitro. RCAF comprises the Drosophila homologue of anti-silencing function 1 protein ASF1 and histones H3 and H4. The specific acetylation pattern of H3 and H4 in RCAF is identical to that of newly synthesized histones. Genetic analyses in Saccharomyces cerevisiae demonstrate that ASF1 is essential for normal cell cycle progression, and suggest that RCAF mediates chromatin assembly after DNA replication and the repair of double-strand DNA damage in vivo.

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    • "As expected, histone proteins associated with chromatin assembly such as HIST1H1D, H2AFZ, and H2AFY were enriched in our proteomic analysis (Fig. 2E), which is consistent with the previous reports that nuclear sirtuins could regulate chromatin structures by deacetylating histone proteins [45] [46] [47], and both SIRT6 and SIRT7 were preferentially localized in the chromatin region [15] [47]. Moreover, chromatin assembly was shown to be coupled to the DNA repair system [48] [49]. SIRT6 regulates chromatin assembly by recruiting SNF2H to DNA break sites and changes chromatin structure by deacetylating H3K56 to promote the recruitment of DNA repair factors [14]. "
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    Proteomics 07/2014; 14(13-14). DOI:10.1002/pmic.201400001 · 3.97 Impact Factor
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    • "Genes Genom strains lacking Vps15 or Vps34 exhibited high sensitivity to HU to a degree comparable with that of the asf1D strain, which is significantly sensitive to HU (Tyler et al. 1999). However, the ESCRT deletion strains and the strain deficient in ESCRT-III adaptor protein Bro1 showed no sensitivity to HU (Fig. 1b). "
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    ABSTRACT: Endosomal sorting complex required for transport (ESCRT) is involved in membrane protein degradation through the recognition and sorting of ubiquitylated cargo proteins into the multivesicular body before fusion with the lysosome/vacuole. However, recent studies have challenged this canonical cellular function of ESCRT and have implicated a role for this machinery in multiple intracellular pathways. Here, we provide evidence that ESCRT complexes contribute to the regulation of transcription elongation in Saccharomyces cerevisiae. Most strains deficient in each subunit of ESCRT-0, -I, -II, and -III showed significant sensitivity to 6-azauracil or mycophenolic acid, a phenotype associated with transcription elongation defects. Moreover, these deletion strains significantly reduced transcription activation through Gcn4, a regulator of the general amino acid control. The transcription factor Rim101, which is proteolytically activated through the multimerized component Vps32/Snf7 of ESCRT-III and its collaborative proteins, was not associated with transcription elongation or Gcn4 activation. In addition, we observed that ESCRT complexes were crosslinked at the 3′ region of the coding sequence in the actively transcribed gene. In summary, these results suggest that ESCRT complexes promote genes transcription during the late stages of elongation and are required for transcription activation through Gcn4.
    Genes & genomics 06/2014; 36(3). DOI:10.1007/s13258-013-0171-8 · 0.57 Impact Factor
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    • "Identified as a single protein in yeast (Le et al. 1997), ASF1 exists as two paralogs in most vertebrates, termed ASF1a and ASF1b in mammals. Among its conserved functions, ASF1 synergizes with two H3–H4 cochaperones: chromatin assembly factor 1 (CAF-1, consisting of three subunits p48, p60, and p150) and histone regulator A (HIRA, homolog of the Hir complex in yeast) to channel the replicative H3.1 and replacement H3.3 histone variants in distinct deposition pathways (Tyler et al. 1999; Mello et al. 2002; Tagami et al. 2004; Green et al. 2005; De Koning et al. 2007; Mousson et al. 2007; Yamane et al. 2011). Although conservation of the ASF1 core binding domain for histones H3–H4 and cochaperones suggests common properties, experimental evidence suggests that the human paralogs are not functionally equivalent (Tagami et al. 2004; Tamburini et al. 2005; English et al. 2006; Tang et al. 2006; De Koning et al. 2007; Mousson et al. 2007; Natsume et al. 2007). "
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