Using electron microscopic techniques such as ultrathin sectioning and freeze-etching we have showed that annulate lamellae,a structure composed of double membrane cisternae studded with nuclear pore complexes, could spontaneously form in activated Xenopus egg extracts without exogenous chromatin or DNA.
用超薄切片电镜技术结合冰冻蚀刻方法观察到在活化的爪蟾卵提取物中环形片层能够自发地大量形成,核孔复合体的超微结构与天然的核孔复合体没有区别,表明核孔复合体的装配能够不依赖于染色质或DNA的诱导而独立进行。