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Kinesin molecular motor Eg5 functions during polypeptide synthesis
Kristen M Bartoli1, Jelena Jakovljevic, John L Woolford
1Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Molecular Biology of the Cell
|July 29, 2011
Summary
The molecular motor Eg5 associates with ribosomes to enhance protein synthesis during interphase. Inhibiting Eg5 disrupts ribosome-microtubule binding and slows polypeptide production, impacting cell division.
Area of Science:
- Molecular biology
- Cell biology
- Biochemistry
Background:
- The kinesin-related motor protein Eg5 is crucial for spindle assembly during cell division.
- The precise functions of Eg5 beyond mitosis are not fully understood.
Purpose of the Study:
- To investigate the role of Eg5 in cellular processes outside of mitosis, specifically during interphase.
- To determine if Eg5 has any association with protein synthesis machinery.
Main Methods:
- In vitro assays to assess ribosome-microtubule binding upon Eg5 inhibition.
- Measurement of ribosome transit rates.
- Analysis of polysome accumulation in cells treated with Eg5 inhibitors.
Main Results:
- Eg5 was found to associate with ribosomes during interphase.
- Eg5 inhibition led to the detachment of ribosomes from microtubules in vitro.
- Ribosome transit rates decreased, and polysomes accumulated in Eg5-inhibited cells, indicating translation defects.
Conclusions:
- The molecular motor Eg5 plays a previously unrecognized role in protein synthesis.
- Eg5 enhances the efficiency of translation by facilitating ribosome function and/or movement along microtubules.
- Eg5's association with ribosomes suggests a novel mechanism for regulating polypeptide synthesis.
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