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Collapsin Response Mediator Protein-1 Regulates Arp2/3-dependent Actin Assembly
Hui-Chia Yu-Kemp1, William M Brieher2
1From the Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Illinois 61820.
The Journal of Biological Chemistry
|November 25, 2015
Summary
Researchers found that CRMP-1 aids Listeria monocytogenes in forming actin comet tails, essential for bacterial movement within host cells. This discovery highlights CRMP-1
Area of Science:
- Cell biology
- Bacteriology
- Biochemistry
Background:
- Listeria monocytogenes utilizes host actin to form comet tails for intracellular motility.
- Actin comet tail formation is more efficient in host cytosol than in vitro, suggesting unknown host factors are involved.
Purpose of the Study:
- To identify host factors that facilitate Arp2/3-dependent actin comet tail formation by Listeria monocytogenes.
- To elucidate the mechanism by which identified factors contribute to bacterial motility.
Main Methods:
- Cytosol fractionation to isolate host proteins.
- Biochemical assays to test the role of isolated factors in actin assembly and Arp2/3 complex activation.
- Assessment of CRMP-1's effect on Listeria actin cloud and comet tail formation.
Main Results:
- CRMP-1 was identified as a host factor that facilitates Arp2/3-dependent actin cloud formation.
- CRMP-1 enhances Listeria actin comet tail formation in brain cytosol.
- CRMP-1 acts as an auxiliary factor, promoting ActA-mediated Arp2/3 complex activation without direct nucleation or activation.
Conclusions:
- CRMP-1 plays a significant role in Listeria actin comet tail formation.
- CRMP-1 may control host cell motility by modulating Arp2/3 complex activation.
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