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Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy
Published on: November 4, 2018
A targeted spatial-temporal proteomics approach implicates multiple cellular trafficking pathways in human
Nathaniel J Moorman1, Ronit Sharon-Friling, Thomas Shenk
1Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.
Molecular & Cellular Proteomics : MCP
|December 22, 2009
Summary
Human cytomegalovirus (HCMV) assembly involves over 60 proteins. This study reveals pUL99 and pUL32 viral proteins traffic via distinct pathways, utilizing cellular machinery like the ESCRT pathway, before merging for virion maturation.
Area of Science:
- Virology
- Cell Biology
- Molecular Biology
Background:
- Human cytomegalovirus (HCMV) virion assembly requires coordinated expression and localization of at least 60 viral proteins.
- Understanding the mechanisms controlling HCMV assembly is crucial for developing antiviral strategies.
Purpose of the Study:
- To investigate the protein interactions and trafficking pathways of essential HCMV assembly proteins pUL99 and pUL32.
- To elucidate the distinct routes these proteins take during early virion assembly.
Main Methods:
- Utilized HCMV strains with green fluorescent protein (GFP) fusions for pUL99 and pUL32.
- Employed immunoisolation and colocalization studies to identify binding partners and cellular pathways.
- Tracked trafficking of pUL99, pUL32, and glycoprotein gB over time.
Main Results:
- pUL99 colocalizes with the endosomal sorting complex required for transport (ESCRT) pathway components.
- pUL32 binds to nucleocapsid and tegument proteins and associates with clathrin, indicating distinct trafficking.
- Glycoprotein gB resides in a separate compartment, with all three merging late in assembly.
Conclusions:
- HCMV assembly involves distinct trafficking pathways for key viral proteins pUL99 and pUL32.
- pUL32 utilizes clathrin-mediated pathways, while pUL99 engages with the ESCRT pathway.
- Virion components traffic independently before merging into a single structure during late assembly stages.
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