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. 2011 Apr 27;2(4):291–302. doi: 10.1007/s13238-011-1038-x

Calcium regulation of nucleocytoplasmic transport

Ashapurna Sarma 1, Weidong Yang 1,✉
PMCID: PMC3387809  NIHMSID: NIHMS385913  PMID: 21528351

Abstract

Bidirectional trafficking of macromolecules between the cytoplasm and the nucleus is mediated by the nuclear pore complexes (NPCs) embedded in the nuclear envelope (NE) of eukaryotic cell. The NPC functions as the sole pathway to allow for the passive diffusion of small molecules and the facilitated translocation of larger molecules. Evidence shows that these two transport modes and the conformation of NPC can be regulated by calcium stored in the lumen of nuclear envelope and endoplasmic reticulum. However, the mechanism of calcium regulation remains poorly understood. In this review, we integrate data on the observations of calciumregulated structure and function of the NPC over the past years. Furthermore, we highlight challenges in the measurements of dynamic conformational changes and transient transport kinetics in the NPC. Finally, an innovative imaging approach, single-molecule superresolution fluorescence microscopy, is introduced and expected to provide more insights into the mechanism of calcium-regulated nucleocytoplasmic transport.

Keywords: nuclear envelope, nuclear pore complex, nucleocytoplasmic transport, calcium stores, single-molecule fluorescence microscopy

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