ATP-dependent positive supercoiling of DNA by 13S condensin: A biochemical implication for chromosome condensation

被引：319

作者：

Kimura, K

Hirano, T

机构：

[1] Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724

来源：

CELL | 1997年 / 90卷 / 04期

关键词：

D O I：

10.1016/S0092-8674(00)80524-3

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

13S condensin is a five-subunit protein complex that plays a central role in mitotic chromosome condensation in Xenopus egg extracts. Two core subunits of this complex, XCAP-C and XCAP-E, belong to an emerging family of putative ATPases, the SMC family. We report here that 13S condensin has a DNA-stimulated ATPase activity and exhibits a high affinity for structured DNAs such as cruciform DNA. 13S condensin is able to introduce positive supercoils into a closed circular DNA in the presence of bacterial or eukaryotic topoisomerase I. The supercoiling reaction is ATP-dependent. We propose that 13S condensin wraps DNA in a right-handed direction by utilizing the energy of ATP hydrolysis. This reaction may represent a key mechanism underlying the compaction of chromatin fibers during mitosis.

引用

页码：625 / 634

页数：10

共 48 条

[41] DNA LOOPING BY THE HMG-BOX DOMAINS OF HMG1 AND MODULATION OF DNA-BINDING BY THE ACIDIC C-TERMINAL DOMAIN [J].