Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba, 278-0022, Japan.
Department of Mechanical Engineering, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, 278-8510, Japan.
Biochem Biophys Res Commun. 2019 Apr 30;512(2):202-207. doi: 10.1016/j.bbrc.2019.03.030. Epub 2019 Mar 14.
Although chromatin condensation is a well-known hallmark of apoptosis, the generation mechanism has not been clarified. Histone H1, a positively-charged abundant nuclear protein, is located in the linker region of chromatin. There are several Histone H1 subtypes that are encoded by variant genes. Using serial histone H1-deletion mutant cells established from the chicken B-cell leukemia line DT40, we found that apoptotic chromatin condensation was decreased in relation to histone H1 protein level and that the chromatin in nuclei prepared from the live null mutant cells had a high accessibility of DNases and transposase. This indicated that linker histone H1 was the general chromatin condensation factor and that the loss of histone H1 generated open chromatin in both apoptotic and live cells.
尽管染色质凝聚是细胞凋亡的一个众所周知的特征，但产生机制尚不清楚。组蛋白 H1 是一种带正电荷的丰富核蛋白，位于染色质的连接区。有几种组蛋白 H1 亚型是由变异基因编码的。使用从鸡 B 细胞白血病系 DT40 中建立的连续组蛋白 H1 缺失突变细胞，我们发现凋亡染色质的凝聚与组蛋白 H1 蛋白水平有关，并且来自活的 null 突变细胞的核中的染色质对 DNase 和转座酶具有高的可及性。这表明连接组蛋白 H1 是一般的染色质凝聚因子，并且组蛋白 H1 的缺失在凋亡和存活细胞中产生开放染色质。
