Related Experiment Videos
Dissecting the interactions between NTF2, RanGDP, and the nucleoporin XFXFG repeats.
C Chaillan-Huntington1, C V Braslavsky, J Kuhlmann
1Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, United Kingdom.
The Journal of Biological Chemistry
|February 22, 2000
Summary
Nuclear transport factor 2 (NTF2) interactions with Ran GTPase and nucleoporins were studied. Ran enhances NTF2 binding to nucleoporins through a novel mechanism, not by altering direct binding affinities.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Nuclear transport is essential for eukaryotic cell function.
- Nuclear transport factor 2 (NTF2) and Ran GTPase are key regulators of nuclear trafficking.
- Nucleoporins containing XFXFG repeats are critical components of the nuclear pore complex.
Purpose of the Study:
- To investigate the binding interactions between NTF2, RanGDP, and XFXFG nucleoporin repeats.
- To elucidate the mechanism by which Ran influences NTF2 binding to nucleoporins.
Main Methods:
- Microcalorimetry
- Microtiter plate binding assays
- Fluorescence quenching
Main Results:
- NTF2-RanGDP binding affinity is in the 100 nM range.
- NTF2-nucleoporin binding affinity is in the 1 microM range.
- Ran binding does not alter the direct affinity between NTF2 and nucleoporins, or NTF2 and RanGDP.
Conclusions:
- Ran enhances NTF2 binding to nucleoporins via an indirect mechanism.
- This mechanism likely involves Ran binding to nucleoporins, with NTF2 subsequently binding to the Ran-nucleoporin complex.
- This provides new insights into the regulation of nuclear transport.