caa a22 4500 463209664 CHVBK 20190327083727.0 cr unu---uuuuu 170326e20071001xx s 000 0 eng 10.1007/s00412-007-0112-x doi (NATIONALLICENCE)springer-10.1007/s00412-007-0112-x The histone chaperone Asf1 is dispensable for direct de novo histone deposition in Xenopus egg extracts [Elektronische Daten] [Dominique Ray-Gallet, Jean-Pierre Quivy, Herman Silljé, Erich Nigg, Geneviève Almouzni] Histone chaperones that escort histones during their overall lifetime from synthesis to sites of usage can participate in various tasks. Their requirement culminates in the dynamic processes of nucleosome assembly and disassembly. In this context, it is important to define the exact role of the histone chaperone Asf1. In mammals, Asf1 interacts with two other chaperones, CAF-1 and HIRA, which are critical in DNA synthesis-coupled and synthesis-uncoupled nucleosome assembly pathways, respectively. A key issue is whether Asf1 is able or not to deposit histones onto DNA by itself in both pathways. Here, to delineate the precise role of Asf1 in chromatin assembly, we used Xenopus egg extracts as a powerful system to assay de novo chromatin assembly pathways in vitro. Following characterization of both Xenopus Asf1 and p60 (CAF-1), we used immunodepletion strategies targeting Asf1, HIRA, or CAF-1. Strikingly, the depletion of Asf1 led to the simultaneous depletion of HIRA and consequently impaired the DNA synthesis-independent nucleosome assembly pathway. The rescue of nucleosome assembly capacity in such extracts was effective when adding HIRA along with H3/H4 histones, yet addition of Asf1 along with H3/H4 histones did not work. Moreover, nucleosome assembly coupled to DNA repair was not affected in these Asf1/HIRA-depleted extracts, a pathway impaired by CAF-1 depletion. Thus, these data show that Asf1 is not directly involved in de novo histone deposition during DNA synthesis-independent and synthesis-dependent pathways in egg extracts. Based on our results, it becomes important to consider the implications for Asf1 function during early development in Xenopus. Springer-Verlag, 2007 Ray-Gallet Dominique Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut Quivy Jean-Pierre Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut Silljé Herman Department of Cell Biology, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany aut Nigg Erich Department of Cell Biology, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany aut Almouzni Geneviève Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut Chromosoma Springer-Verlag 116/5(2007-10-01), 487-496 0009-5915 116:5<487 2007 116 412 https://doi.org/10.1007/s00412-007-0112-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00412-007-0112-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ray-Gallet Dominique Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut NATIONALLICENCE 700 1- Quivy Jean-Pierre Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut NATIONALLICENCE 700 1- Silljé Herman Department of Cell Biology, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany aut NATIONALLICENCE 700 1- Nigg Erich Department of Cell Biology, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, 82152, Martinsried, Germany aut NATIONALLICENCE 700 1- Almouzni Geneviève Section de Recherche, UMR 218 du CNRS, Institut Curie, 26 rue d'Ulm, 75248, Paris Cedex 05, France aut NATIONALLICENCE 773 0- Chromosoma Springer-Verlag 116/5(2007-10-01), 487-496 0009-5915 116:5<487 2007 116 412 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer