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Published on: November 11, 2018
Dynamic localisation of Ran GTPase during the cell cycle
James R A Hutchins1, William J Moore, Paul R Clarke
1Biomedical Research Institute, College of Medicine, Dentistry and Nursing, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK. hutchins@imp.ac.at
BMC Cell Biology
|September 22, 2009
Summary
Ran GTPase dynamics are crucial for cell division. Its interactions with chromatin, nuclear pores, and the spindle depend on its nucleotide-bound state, influencing nuclear transport and spindle assembly.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Ran GTPase regulates key cell division processes like nucleocytoplasmic transport, mitotic spindle assembly, and nuclear envelope formation.
- Ran's activity is controlled by its guanine nucleotide-bound state and subcellular localization.
Purpose of the Study:
- To characterize the localization and mobility of Ran-green fluorescent protein (GFP) during the cell cycle in live human cells.
- To investigate how different nucleotide-bound states of Ran affect its interactions within the cell.
Main Methods:
- Live-cell imaging of human cells expressing Ran fused to green fluorescent protein (GFP).
- Characterization of wild-type Ran-GFP and specific mutants (RanQ69L, RanT24N) during different cell cycle phases.
Main Results:
- Ran-GFP localizes to the nucleus during interphase and disperses during mitosis.
- The GTP-bound mutant (GFP-RanQ69L) shows reduced nuclear concentration and associates with nuclear pore complexes, localizing to the spindle during mitosis.
- The nucleotide-binding deficient mutant (GFP-RanT24N) stably interacts with chromatin throughout the cell cycle and concentrates on mitotic chromosomes.
Conclusions:
- Ran exhibits dynamic interactions with chromatin, nuclear pore complexes, and the mitotic spindle, contingent on its nucleotide-bound state.
- Ran-GTP generated at chromatin is highly mobile and interacts with structures vital for nuclear transport and spindle assembly.
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