Yukioka M, Sasaki S, Qi S L, Inoue A
J Biol Chem. 1984 Jul 10;259(13):8372-7.
Subcellular localization of histone acetyltransferase was studied in rat liver cells. Two histone acetyltransferases, designated NI and NII, were identified in the nuclear fraction, and an additional two acetyltransferases, termed CI and CII, were separated from the cytoplasmic fraction. These acetyltransferases exhibited different substrate specificities toward free and nucleosomal histones. The enzymes NI and NII represented major histone acetyltransferase activities in rat liver nuclei, and they were further differentiated by DNA-binding properties, subnuclear localization, and reaction kinetics. While the NI enzyme exhibited an intersecting initial velocity kinetic, the NII enzyme followed a ping-pong initial velocity pattern. These results show the multiple occurrence of histone acetyltransferases in nuclear and cytoplasmic fractions, events which may reflect the complexities of histone acetylation.
在大鼠肝细胞中研究了组蛋白乙酰转移酶的亚细胞定位。在细胞核部分鉴定出两种组蛋白乙酰转移酶，分别命名为NI和NII，另外从细胞质部分分离出两种乙酰转移酶，称为CI和CII。这些乙酰转移酶对游离组蛋白和核小体组蛋白表现出不同的底物特异性。酶NI和NII代表大鼠肝细胞核中的主要组蛋白乙酰转移酶活性，它们通过DNA结合特性、亚核定位和反应动力学进一步区分。虽然NI酶表现出相交的初速度动力学，NII酶遵循乒乓初速度模式。这些结果表明组蛋白乙酰转移酶在细胞核和细胞质部分中多次出现，这些事件可能反映了组蛋白乙酰化的复杂性。
