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Updated: Jul 16, 2026
12:13
Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
Cell cycle regulated transport controlled by alterations in the nuclear pore complex
Taras Makhnevych1, C Patrick Lusk, Andrea M Anderson
1Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
Cell
|December 31, 2003
Summary
Nuclear pore complex (NPC) rearrangements during mitosis regulate nuclear transport. A specific protein (Nup53p) inhibits karyopherin Kap121p, controlling cell cycle progression in yeast.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Eukaryotic cells regulate nuclear transport for cell cycle control.
- Nuclear transport mechanisms must function during mitosis, even when the nuclear envelope is intact.
- The nuclear pore complex (NPC) is central to regulating molecule movement between the nucleus and cytoplasm.
Purpose of the Study:
- To uncover the mechanism of transport regulation during mitosis.
- To investigate the role of M phase-specific changes in the NPC.
- To understand how nuclear transport impacts cell cycle progression.
Main Methods:
- Studied yeast cells to observe NPC dynamics during mitosis.
- Investigated the interaction between Nup53p and Kap121p.
- Analyzed yeast strains with defects in Kap121p or the inhibitory pathway.
Main Results:
- Identified M phase-specific molecular rearrangements in the NPC.
- Demonstrated that Nup53p binds Kap121p during mitosis, inhibiting its transport.
- Observed mitotic delays in yeast strains with defects in Kap121p or the Nup53p-mediated pathway.
Conclusions:
- NPC-mediated regulation of Kap121p transport is crucial for mitosis.
- This pathway controls the distribution of proteins essential for cell cycle progression.
- The findings reveal a novel mechanism for cell cycle control via regulated nuclear transport.
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