Related Experiment Videos
MasterCARD: a priceless link to innate immunity.
John Hiscott1, Rongtuan Lin, Peyman Nakhaei
1Lady Davis Institute for Medical Research--Jewish General Hospital, Department of Microbiology & Immunology, McGill University, Montreal, QC, H3T 1E2, Canada. john.hiscott@mcgill.ca
Trends in Molecular Medicine
|January 13, 2006
Summary
The RIG-I pathway detects viral RNA, activating innate immunity through the MAVS/IPS-1/VISA/Cardif adaptor. Hepatitis C virus targets this molecule, revealing mitochondria's role in immunity and apoptosis.
Area of Science:
- Immunology
- Virology
- Cell Biology
Background:
- Intracellular viral infections trigger host defense mechanisms.
- Cytoplasmic RNA helicase RIG-I is crucial for initiating antiviral responses.
- The adaptor molecule linking RIG-I to downstream signaling was recently identified.
Purpose of the Study:
- To elucidate the function and identity of the adaptor molecule connecting RIG-I to downstream signaling.
- To investigate the role of mitochondria in the innate immune response to viral infection.
- To understand the mechanism of immune evasion employed by Hepatitis C virus.
Main Methods:
- Identification of the MAVS/IPS-1/VISA/Cardif adaptor molecule.
- Localization studies of MAVS/IPS-1/VISA/Cardif to the mitochondrial membrane.
- Analysis of Hepatitis C virus NS3/4A protease activity on MAVS/IPS-1/VISA/Cardif.
Main Results:
- The adaptor molecule, named MAVS, IPS-1, VISA, and Cardif, connects RIG-I to signaling pathways.
- MAVS/IPS-1/VISA/Cardif localizes to mitochondria, linking viral sensing to mitochondrial function.
- Hepatitis C virus protease cleaves MAVS/IPS-1/VISA/Cardif, inhibiting the antiviral response.
Conclusions:
- Mitochondria play a significant role in innate immunity coordination.
- Caspase activation and recruitment domain (CARD)-containing proteins are key in immune and apoptotic responses.
- Targeting the MAVS/IPS-1/VISA/Cardif pathway is a viral immune evasion strategy.