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A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells
Published on: July 31, 2012
Cell surface receptors for gammaretroviruses
C S Tailor1, D Lavillette, M Marin
1Infection, Immunity Injury and Repair Program, Hospital for Sick Children, Toronto, ON M5G 1XB, Canada.
Current Topics in Microbiology and Immunology
|August 23, 2003
Summary
Gamma-retroviruses uniquely use multi-transmembrane (TM) domain proteins as receptors, unlike other viruses that use single-TM receptors. This evolutionary adaptation influences host specificity and viral survival strategies.
Area of Science:
- Virology
- Molecular Biology
- Evolutionary Biology
Background:
- Cell surface receptors are crucial for viral entry, mediating direct conformational changes in viral envelope glycoproteins.
- Gamma-retroviruses exhibit unique receptor usage patterns compared to other animal viruses.
Purpose of the Study:
- To elucidate the structural and functional characteristics of gamma-retroviral cell surface receptors.
- To understand the evolutionary implications of receptor usage in gamma-retrovirus adaptation and host specificity.
Main Methods:
- Comparative analysis of viral receptor structures (single vs. multiple transmembrane domains).
- Investigation of evolutionary pathways and host-species jumping (zoonoses) in gamma-retroviruses.
- Examination of viral-host coevolutionary dynamics at receptor interaction sites.
Main Results:
- All gamma-retroviral receptors identified possess multiple transmembrane (TM) sequences, contrasting with the single-TM receptors of most other animal viruses.
- Gamma-retroviruses utilize pairs of related receptors, enhancing viral survival by limiting host escape mutations.
- Receptor hypervariable regions, though glycosylated, interact with conserved functional sites, suggesting a host defense mechanism.
Conclusions:
- Gamma-retroviral receptor usage (multi-TM) is a distinct evolutionary trait, likely preventing switches to single-TM receptor systems.
- The complexity of gamma-retroviral entry involves glycoprotein cross-talk triggered by receptor interaction, not just direct conformational changes.
- Cell surface receptors play a more intricate role in gamma-retroviral infections than previously understood, impacting viral evolution and host interactions.
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