A HETERODIMERIC COILED-COIL PROTEIN REQUIRED FOR MITOTIC CHROMOSOME CONDENSATION IN-VITRO
A HETERODIMERIC COILED-COIL PROTEIN REQUIRED FOR MITOTIC CHROMOSOME CONDENSATION IN-VITRO
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DOI：
10.1016/0092-8674(94)90254-2
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发表时间：
1994-11-04
期刊：
影响因子：
64.5
通讯作者：
MITCHISON, TJ
中科院分区：
文献类型：
--
作者：
HIRANO, T;MITCHISON, TJ
我们在此报告了一种在爪蟾卵提取物中有丝分裂染色体凝聚中起重要作用的染色体蛋白。两个多肽，命名为XCAP-C和XCAP-E，被发现在提取物中相互结合，可能形成异二聚体。在有丝分裂提取物的染色体组装过程中，XCAP-C/E被招募到染色质上，并在组装的染色体内形成离散的内部结构。抗体阻断实验表明XCAP-C的功能是体外有丝分裂染色体组装和结构维持所必需的。推导出的氨基酸序列表明，这两个多肽具有共同的结构基序，包括一个n端ntp结合域、两个中心卷曲区和一个c端保守域。这些基序在一个蛋白质家族中是高度保守的，最近在原核生物和真核生物中都发现了该家族的成员。
We report here a chromosomal protein that plays an essential role in mitotic chromosome condensation in Xenopus egg extracts. Two polypeptides, designated XCAP-C and XCAP-E, were found to associate with each other in the extracts, presumably forming a heterodimer. During chromosome assembly in mitotic extracts, XCAP-C/E was recruited to the chromatin and formed a discrete internal structure within assembled chromosomes. Antibody blocking experiments showed that XCAP-C function is required for both assembly and structural maintenance of mitotic chromosomes in vitro. Deduced amino acid sequences revealed that the two polypeptides share common structural motifs, consisting of an N-terminal NTP-binding domain, two central coiled-coil regions, and a C-terminal conserved domain. These motifs are highly conserved in a protein family, members of which have been identified recently in both prokaryotes and eukaryotes.