Wirbelauer Christiane, Bell Oliver, Schübeler Dirk
Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland.
Genes Dev. 2005 Aug 1;19(15):1761-6. doi: 10.1101/gad.347705.
Deposition of variant histones provides a mechanism to reset and to potentially specify chromatin states. We determined the distribution of H3 and its variant H3.3 relative to chromatin structure and elongating polymerase. H3.3 is enriched throughout active genes similar to polymerase, yet its distribution is very distinct from that of several euchromatic histone modifications, which are highly biased toward the 5' part of active genes. Upon gene induction we observe displacement of both H3 and H3.3 followed by selective deposition of H3.3. These results support a model in which H3.3 deposition compensates for transcription-coupled nucleosomal displacement yet does not predetermine tail modifications.
变异组蛋白的沉积提供了一种重置并可能指定染色质状态的机制。我们确定了H3及其变体H3.3相对于染色质结构和延伸中的聚合酶的分布。H3.3在整个活跃基因中富集，类似于聚合酶，但其分布与几种常染色质组蛋白修饰的分布非常不同，这些修饰高度偏向于活跃基因的5'端。在基因诱导后，我们观察到H3和H3.3都发生了置换，随后是H3.3的选择性沉积。这些结果支持了一个模型，即H3.3的沉积补偿了转录偶联的核小体置换，但并不预先决定尾部修饰。
