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Updated: Mar 13, 2026
13:04
A Protocol for Analyzing Hepatitis C Virus Replication
Published on: June 26, 2014
24.8K
Hepatitis C virus promotes virion secretion through cleavage of the Rab7 adaptor protein RILP
Ann L Wozniak1, Abby Long1, Kellyann N Jones-Jamtgaard1
1Department of Internal Medicine and Liver Center, University of Kansas Medical Center, Kansas City, KS 66160.
Summary
Hepatitis C virus (HCV) infection cleaves the Rab7 adaptor protein RILP, disrupting endosome-lysosome fusion and redirecting viral particles for secretion. This viral strategy hijacks cellular trafficking for efficient spread.
Area of Science:
- Virology
- Cell Biology
- Molecular Mechanisms
Background:
- Hepatitis C virus (HCV) alters intracellular trafficking, but mechanisms are unclear.
- Viruses manipulate host cell processes for replication and spread.
- Endosome-lysosome fusion is critical for cellular waste disposal and signaling.
Purpose of the Study:
- To investigate how HCV and other viruses modify intracellular trafficking.
- To elucidate the role of Rab7-dependent pathways in viral infection.
- To identify viral strategies for manipulating host cell transport.
Main Methods:
- Observed effects of HCV and Sendai virus on Rab7-dependent endosome-lysosome fusion.
- Analyzed cleavage of the Rab7 adaptor protein RILP (Rab interacting lysosomal protein).
- Utilized RILP knockdown and expression of cleaved RILP (cRILP) to assess trafficking defects.
Main Results:
- HCV and Sendai virus inhibit Rab7-dependent endosome-lysosome fusion by cleaving RILP.
- Cleaved RILP (cRILP) relocates to the cell periphery, causing trafficking defects.
- Expression of cRILP mimics HCV-induced trafficking defects and promotes virus secretion.
- Viral RILP cleavage redirects Rab7 vesicles to kinesin-dependent transport for secretion.
Conclusions:
- HCV hijacks cellular trafficking by cleaving RILP, a novel viral mechanism.
- RILP cleavage promotes virion secretion by redirecting vesicles.
- Understanding viral manipulation of host trafficking is key to antiviral strategies.
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