ASF1 Binds to a Heterodimer of Histones H3 and H4: A Two-Step Mechanism for the Assembly of the H3-H4 Heterotetramer on DNA

详细信息    查看全文

• 作者：Christine M. English ; Nasib K. Maluf ; Brian Tripet ; Mair E. A. Churchill ; and Jessica K. Tyler
• 刊名：Biochemistry
• 出版年：2005
• 出版时间：October 25, 2005
• 年：2005
• 卷：44
• 期：42
• 页码：13673 - 13682
• 全文大小：420K
• 年卷期：v.44,no.42(October 25, 2005)
• ISSN：1520-4995

文摘

The first step in the formation of the nucleosome is commonly assumed to be the depositionof a histone H3-H4 heterotetramer onto DNA. Antisilencing function 1 (ASF1) is a major histone H3-H4 chaperone that deposits histones H3 and H4 onto DNA. With a goal of understanding the mechanismof deposition of histones H3 and H4 onto DNA, we have determined the stoichiometry of the Asf1-H3-H4 complex. We have established that a single molecule of Asf1 binds to an H3-H4 heterodimerusing gel filtration, amino acid, reversed-phase chromatography, and analytical ultracentrifugation analyses.We demonstrate that Asf1 blocks formation of the H3-H4 heterotetramer by a mechanism that likelyinvolves occlusion of the H3-H3 dimerization interface.