Experimental Research Center for Infectious Diseases, Institute for Virus Research, Kyoto University, Kyoto, Japan.
Nucleic Acids Res. 2010 Jun;38(11):3533-45. doi: 10.1093/nar/gkq076. Epub 2010 Feb 15.
In eukaryotic nuclei, DNA is wrapped around an octamer of core histones to form nucleosomes, and chromatin fibers are thought to be stabilized by linker histones of the H1 type. Higher eukaryotes express multiple variants of histone H1; chickens possess six H1 variants. Here, we generated and analyzed the phenotype of a complete deletion of histone H1 genes in chicken cells. The H1-null cells showed decreased global nucleosome spacing, expanded nuclear volumes, and increased chromosome aberration rates, although proper mitotic chromatin structure appeared to be maintained. Expression array analysis revealed that the transcription of multiple genes was affected and was mostly downregulated in histone H1-deficient cells. This report describes the first histone H1 complete knockout cells in vertebrates and suggests that linker histone H1, while not required for mitotic chromatin condensation, plays important roles in nucleosome spacing and interphase chromatin compaction and acts as a global transcription regulator.
在真核细胞核中，DNA 缠绕在核心组蛋白的八聚体周围形成核小体，染色质纤维被认为通过 H1 型连接组蛋白稳定。高等真核生物表达多种组蛋白 H1 变体；鸡拥有六种 H1 变体。在这里，我们生成并分析了鸡细胞中组蛋白 H1 基因完全缺失的表型。H1 缺失细胞表现出全局核小体间距减小、核体积增大和染色体畸变率增加，尽管有适当的有丝分裂染色质结构。表达谱分析显示，多个基因的转录受到影响，在缺乏组蛋白 H1 的细胞中大多下调。本报告描述了脊椎动物中第一个组蛋白 H1 完全敲除细胞，并表明连接组蛋白 H1 虽然不是有丝分裂染色质凝聚所必需的，但在核小体间距和有丝分裂间期染色质紧缩中发挥重要作用，并作为一个全局转录调节剂。
