Scharf Annette N D, Meier Karin, Seitz Volker, Kremmer Elisabeth, Brehm Alexander, Imhof Axel
Munich Centre of Integrated Protein Science and Adolf-Butenandt Institute, Ludwig Maximilians University of Munich, Schillerstr. 44, 80336 Munich, Germany.
Mol Cell Biol. 2009 Jan;29(1):57-67. doi: 10.1128/MCB.00989-08. Epub 2008 Nov 10.
Histone modifications play an important role in shaping chromatin structure. Here, we describe the use of an in vitro chromatin assembly system from Drosophila embryo extracts to investigate the dynamic changes of histone modifications subsequent to histone deposition. In accordance with what has been observed in vivo, we find a deacetylation of the initially diacetylated isoform of histone H4, which is dependent on chromatin assembly. Immediately after deposition of the histones onto DNA, H4 is monomethylated at K20, which is required for an efficient deacetylation of the H4 molecule. H4K20 methylation-dependent dl(3)MBT association with chromatin and the identification of a dl(3)MBT-dRPD3 complex suggest that a deacetylase is specifically recruited to the monomethylated substrate through interaction with dl(3)MBT. Our data demonstrate that histone modifications are added and removed during chromatin assembly in a highly regulated manner.
组蛋白修饰在塑造染色质结构中起着重要作用。在此，我们描述了利用果蝇胚胎提取物的体外染色质组装系统，来研究组蛋白沉积后组蛋白修饰的动态变化。与体内观察到的情况一致，我们发现最初二乙酰化的组蛋白H4亚型发生了去乙酰化，这依赖于染色质组装。组蛋白沉积到DNA上后，H4在K20位点立即发生单甲基化，这是H4分子高效去乙酰化所必需的。H4K20甲基化依赖的dl(3)MBT与染色质的结合以及dl(3)MBT-dRPD3复合物的鉴定表明，一种去乙酰化酶通过与dl(3)MBT相互作用而被特异性招募到单甲基化底物上。我们的数据表明，在染色质组装过程中，组蛋白修饰以高度调控的方式被添加和去除。
