Stewart M, Whytock S, Moir R D
MRC Laboratory of Molecular Biology, Cambridge, England.
J Cell Sci Suppl. 1991;14:79-82. doi: 10.1242/jcs.1991.supplement_14.16.
We have combined structural, biochemical and recombinant DNA methods to explore molecular interactions involved in nuclear envelope assembly dynamics and nucleocytoplasmic transport. Electron microscopy has established the overall architecture of the envelope and the relationship between nuclear pores, lamina fibres and pore-connecting fibrils. The lamin proteins that constitute the lamina resemble intermediate filament proteins, and assemble and disassemble during mitosis in response to phosphorylation. Lamins have been expressed in E. coli to facilitate structural investigations and the exploration of interaction sites with other envelope components. Disruption of envelopes has shown that nuclear pores are constructed from a central cylinder with cytoplasmic and nucleoplasmic rings. Examination of envelopes transporting gold-labelled nucleoplasmin has indicated that the transport pathway is complex and probably involves ring components in addition to the central cylinder. Molecular motors may be involved in changes in pore shape to enable transport and in the translocation mechanism.
我们结合了结构、生化和重组DNA方法，以探索核膜组装动力学和核质运输中涉及的分子相互作用。电子显微镜已确定了核膜的整体结构以及核孔、核纤层纤维和孔连接纤维之间的关系。构成核纤层的核纤层蛋白类似于中间丝蛋白，并在有丝分裂期间响应磷酸化而组装和拆卸。核纤层蛋白已在大肠杆菌中表达，以促进结构研究以及探索与其他核膜成分的相互作用位点。对核膜的破坏表明，核孔由带有细胞质环和核质环的中央圆柱构成。对运输金标记核质蛋白的核膜的检查表明，运输途径很复杂，除了中央圆柱外，可能还涉及环成分。分子马达可能参与孔形状的变化以实现运输以及转运机制。
