Condensins, chromosome condensation protein complexes containing XCAP-C, XCAP-E and a Xenopus homolog of the Drosophila Barren protein
Condensins, chromosome condensation protein complexes containing XCAP-C, XCAP-E and a Xenopus homolog of the Drosophila Barren protein
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DOI：
10.1016/s0092-8674(00)80233-0
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发表时间：
1997-05-16
期刊：
影响因子：
64.5
通讯作者：
Hirano, M
中科院分区：
文献类型：
--
作者：
Hirano, T;Kobayashi, R;Hirano, M
我们在这里报告的纯化和染色体凝聚蛋白复合物（称为凝聚素）含有XCAP-C和XCAP-E，两个非洲爪蟾SMC家族的成员。蔗糖密度梯度离心揭示了两种主要形式的凝聚素。8 S形式是XCAP-C和XCAP-E的异二聚体，而13 S形式含有三个额外的亚基。其中之一被鉴定为果蝇Barren蛋白的同源物，其突变显示染色体分离缺陷。凝聚素的染色体靶向是有丝分裂特异性的，并且不依赖于拓扑异构酶II α。免疫耗竭和拯救实验证明，凝聚需要13 S凝聚素。我们的研究结果表明，凝聚素复合物代表了最丰富的有丝分裂染色体的结构组成部分，并在驱动染色体凝聚中发挥核心作用。
We report here purification and characterization of chromosome condensation protein complexes (termed condensins) containing XCAP-C and XCAP-E, two Xenopus members of the SMC family. Sucrose density gradient centrifugation reveals two major forms of condensins. The 8S form is a heterodimer of XCAP-C and XCAP-E, whereas the 13S form contains three additional subunits. One of them is identified as a homolog of the Drosophila Barren protein whose mutation shows a defect in chromosome segregation. Chromosomal targeting of condensins is mitosis-specific and is independent of topoisomerase II alpha. 13S condensin is required for condensation, as demonstrated by immunodepletion and rescue experiments. Our results suggest that the condensin complexes represent the most abundant structural components of mitotic chromosomes and play a central role in driving chromosome condensation.