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Updated: May 2, 2026
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Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
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Nuclear pores set the speed limit for mitosis
Abigail Buchwalter1, Martin W Hetzer1
1Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, 92037 CA, USA.
Cell
|March 4, 2014
Summary
The nuclear pore complex acts as a scaffold for the spindle assembly checkpoint during interphase. This interaction stores inhibitory signals, ultimately controlling the pace of mitosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The spindle assembly checkpoint (SAC) is crucial for accurate chromosome segregation.
- SAC ensures that sister chromatids do not separate until kinetochores are properly attached to the mitotic spindle.
- Dysregulation of SAC can lead to aneuploidy and disease.
Purpose of the Study:
- To investigate the role of the nuclear pore complex (NPC) in SAC signaling.
- To understand how NPC influences the timing of mitosis.
Main Methods:
- Immunofluorescence microscopy
- Biochemical assays
- Cell cycle analysis
Main Results:
- The NPC scaffolds SAC signaling components during interphase.
- NPC sequesters inhibitory SAC signals in interphase.
- This sequestration limits the rate of entry into mitosis.
Conclusions:
- The nuclear pore complex plays a novel role in regulating the spindle assembly checkpoint.
- NPC acts as a reservoir for SAC inhibitory signals, controlling mitotic timing.
- This finding provides new insights into cell cycle regulation and chromosome segregation.
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