甲藻染色体在非细胞体系核重建过程中核小体的组装  

Nucleosomal Assembly in Vitro from Crypthecodinium cohnii Chromosomes in the Cell-free System

作　　者：刘晓玲[1] 陶伟[1] 高云飞[1] 卢智刚[1] 翟中和[1] 

机构地区：[1]北京大学生命科学学院,北京100871

出　　处：《Acta Botanica Sinica》2001年第12期1224-1228,共5页Acta Botanica Sinica（植物学报：英文版）

基　　金：国家自然科学基金 ( 39730 2 40 )~~

摘　　要：利用纯化的原始真核生物寇氏隐甲藻 (CrypthecodiniumcohniiE .)染色体 ,使之与非洲爪蟾 (XenopuslaevisL .)S期卵提取物温育 ,发现甲藻染色体经历了一系列去凝集、再凝集的形态变化 ,最后形成类似典型高等真核生物的间期核结构。小球菌核酸酶酶切分析表明 ,不具备组蛋白和核小体结构的甲藻染色体在非洲爪蟾卵提取物中进行了核小体装配 ,此过程与DNA序列本身、核膜以及核纤层蛋白 (Lamin)是否存在无关 ,但部分拓扑异构酶Ⅱ (TopoⅡ )参与了这个过程 ,说明核小体的组装并非为核重建所必需 ,决定染色体高级结构的因素并不在DNA本身 。The typical eukaryote interphase nuclei were reconstructed in vitrofollowing incubation of chromosomes of primitive eukaryote dinoflagellate Crypthecodinium cohniiE. in extracts of S phase eggs of Xenopus laevisL. Micrococcal nuclease digestion experiments indicated that the reconstructed nuclei contained typical nucleosomes. Since the chromosomes of C. cohniido not contain histone and nucleosomes, these data suggest that nucleosome assembly is independent of specific DNA sequences, nuclear membranes and Lamin. Moreover, it has been demonstrated that Topoisomerase Ⅱ was partially involved in the process of nucleosome assembly. Taken together, these findings suggest that nuclear assembly is independent of formation of nucleosomes and that histone and non-histone may be the decisive factors in this process.

关 键 词：甲藻 染色体 非细胞体系 核重建 核小体装配 

分 类 号：Q943[生物学—植物学]