结核分枝杆菌H37Rv ORF的高通量克隆和表达方法的建立

以结核分枝杆菌H37Rv基因组为模板,采用Gateway重组表达系统,以基因长度200～2500 bp为标准,选择目的基因（n=384）,以ORF的保守序列设计引物并加上正反向AttB,通过PCR扩增获得基因片段检测入门克隆,得到的克隆有效率为374/384。通过两次同源重组,这些基因片段被克隆到表达载体中,克隆效率为350/384。随后将这些重组表达质粒分别在2个表达菌株BL21和BL21-codonplus-RP中进行诱导表达,表达得率为270/384,并对其中64个进行了纯化,16个是可溶性表达。这种大规模高效率地克隆表达技术适合各种生物的开放阅读框的克隆表达,是一种高通量的克隆表达方法。

Nuclear assembly of purified Crythecodinium cohnii chromosomes in cell-free extracts of Xenopus laevis eggs

Incubation of dinoflagellate Crythecodinium cohnii chromosomes in cytoplasmic extracts of unfertilized Xenopus laevis eggs resulted in chromosomes decondensation and recondensation, nuclear envelope assembly, and nuclear reconstitution.Dinoflagellate Crythecodinium cohnii is a kind of primitive eukaryote which possesses numerous permanently condensed chromosomes and discontinuous double-layered nuclear membrane throughout the cell cycle. The assembled nuclei, being surrounded by a continuous double membrane containing nuclear pores and the uniformly dispersed chromatin fibers are morphologically distinguishable from that of Dinoflagellate Crythecodinium cohnii. However, incubation of dinoflagellate Crythecodinium cohnii chromosomes in the extracts from dinoflagellate Crythecodinillm cohnii cells does not induce nuclear reconstitution.