Related Experiment Videos
Multiple pathways contribute to nuclear import of core histones
P Mühlhäusser1, E C Müller, A Otto
1ETH Zürich, Institut für Biochemie, Universitätsstrasse 16, 8092 Zürich, Switzerland and 1Max-Delbrück-Centrum, Robert-Rössle-Strasse 10, 13122 Berlin-Buch, Germany.
EMBO Reports
|August 9, 2001
Summary
Nuclear import of core histones is mediated by importins, a family of transport receptors. This study identifies importin 9 as a key player in histone nuclear transport during the cell cycle.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Nuclear import of core histones (H2A, H2B, H3, H4) is crucial during S-phase.
- The molecular mechanisms governing histone nuclear import remain largely unknown.
Purpose of the Study:
- To elucidate the pathways and molecular machinery responsible for nuclear import of core histones.
- To identify specific importin proteins involved in histone nuclear transport.
Main Methods:
- Competition assays using the BIB domain of ribosomal protein L23a.
- Affinity chromatography with immobilized core histones.
- Nuclear import assays in permeabilized cells.
Main Results:
- Core histone import is an importin-mediated process, evidenced by competition assays.
- Several importin-beta family members bind to core histones.
- Importin 9, along with four known importins, mediates core histone nuclear import.
Conclusions:
- Multiple importin-mediated pathways facilitate the efficient nuclear uptake of core histones.
- Importin 9 plays a significant role in histone nuclear transport.
- Understanding these pathways is essential for comprehending nuclear transport regulation.