Dou Yali, Gorovsky Martin A
Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Proc Natl Acad Sci U S A. 2002 Apr 30;99(9):6142-6. doi: 10.1073/pnas.092029599. Epub 2002 Apr 23.
In Tetrahymena cells, constitutive phosphorylation of histone H1 phenocopies the loss of H1 from chromatin. Regulation of transcription by H1 phosphorylation is achieved by altering the overall charges of a small domain. Here, we further explore the electrostatic properties of this domain and the mechanism by which it regulates transcription. We demonstrate that the regulatory effect of the clustered charges does not require any long-range interaction and is position independent. However, when the same number of charges was dispersed throughout the H1 molecule, the effect became undetectable. The results are explained by a nucleation-propagation model and provide in vivo evidence that the synergy of the clustered positive charges plays a role in histone function and gene regulation.
在四膜虫细胞中，组蛋白H1的组成型磷酸化模拟了染色质中H1的缺失。H1磷酸化对转录的调控是通过改变一个小结构域的整体电荷来实现的。在这里，我们进一步探究该结构域的静电特性及其调控转录的机制。我们证明，成簇电荷的调控作用不需要任何长程相互作用，且与位置无关。然而，当相同数量的电荷分散在整个H1分子中时，这种作用就变得无法检测到。这些结果由一个成核-传播模型进行解释，并提供了体内证据，表明成簇正电荷的协同作用在组蛋白功能和基因调控中发挥作用。
