一种ATP依赖的核小体重塑因子的纯化及特性

Purification and properties of an ATP-dependent nucleosome remodeling factor.

作者信息

Tsukiyama T, Wu C

机构信息

Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA.

出版信息

Cell. 1995 Dec 15;83(6):1011-20. doi: 10.1016/0092-8674(95)90216-3.

DOI:10.1016/0092-8674(95)90216-3

PMID:8521501

Abstract

We report the purification of an ATP-dependent nucleosome remodeling factor (NURF) from Drosophila embryo extracts. NURF is composed of at least four polypeptides that act in concert with the GAGA transcription factor to alter chromatin structure at the hsp70 promoter. The energy requirement is attributed to an ATPase activity that is stimulated by nucleosomes but not by free DNA or histones, suggesting that NURF acts directly on a nucleosome to perturb its structure. This finding and the physical properties of NURF contrast sharply with the multisubunit SWI2/SNF2 complex, which has also been shown to alter nucleosomes in an ATP-dependent manner. The results suggest that two distinct systems may be involved in remodeling chromatin for transcription.

摘要

我们报道了从果蝇胚胎提取物中纯化出一种ATP依赖的核小体重塑因子（NURF）。NURF由至少四种多肽组成，这些多肽与GAGA转录因子协同作用，改变hsp70启动子处的染色质结构。能量需求归因于一种ATP酶活性，该活性受到核小体的刺激，但不受游离DNA或组蛋白的刺激，这表明NURF直接作用于核小体以扰乱其结构。这一发现以及NURF的物理特性与多亚基SWI2/SNF2复合物形成鲜明对比，后者也已被证明以ATP依赖的方式改变核小体。结果表明，可能有两种不同的系统参与染色质重塑以进行转录。