应用大肠杆菌染色体DNA在非洲爪蟾卵提取物实现诱导非细胞体系核装配  

NUCLEAR RECONSTITUTION AROUND PURIFIED E. COLI DNA IN CELL-FREE EXTRACTS OF XENOPUS LAEVIS EGGS

作　　者：蒋争凡[1] 曲健[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：《实验生物学报》1997年第2期183-191,共9页Acta Biologiae Experimentalis Sinica

摘　　要：近年来我们实验室已成功地利用细胞核体外组装的实验模式,将多种生物的DNA在非洲爪蟾卵提取物中实现了非细胞体系核装配。但亲缘关系最远的原核生物的染色体DNA是否也能在此真核体系中进行核装配一直没有报道。我们以大肠杆菌染色体DNA为材料,研究了它诱导的非细胞体系核装配。在光镜与电镜水平观察了核装配的过程。显微分光光度计扫描显示DNA片段在核装配过程中经历了凝集-去凝集的变化。证明大肠杆菌染色体DNA也能诱导爪蟾卵提取物装配成具有典型结构的核。α-^(32)P-dCTP的掺入实验表明重建核具有较高的DNA复制活性。In recent years we have succeeded in inducing various exogenous DNA to assembly typical nuclei in cell-free Xenopus egg extracts. However, it is not clear if prokaryotic chromosomal DNA can also form the nucleus in this eukaryotic system. In our experiment, we used the purified E. coli. chromosomal DNA to reconstitute the nucleus in the nuclear recon-stitution extracts and found that typical nuclei can also be assembled around addedDNA. We observed the process of nuclear reconstitution by using light microscopy and electronic microscopy. The scanning results of chromatin-like materials and assembled nuclei by microspectrophotometer showed that E. coli, chromosal DNA underwent obvious change from condensation to decondensation during nuclear reconstitution. Incorporation of α-32P-dCTP into DNA suggested that the reconstituted nuclei were capable of DNA replication.

关 键 词：大肠杆菌 DNA 非洲爪蟾卵 非细胞体系 核装配 

分 类 号：Q27[生物学—细胞生物学]