RIPK3-Dependent Necroptosis Limits PRV Replication in PK-15 Cells
Hongchao Gou1,2,3,4, Zhibiao Bian1,2,3,4, Rujian Cai1,2,3,4
1Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China.
Frontiers in Microbiology
|June 21, 2021
Summary
Pseudorabies virus (PRV) triggers programmed cell death called necroptosis in pigs. This necroptosis limits PRV infection, suggesting it could be a target for controlling the disease.
Area of Science:
- Virology
- Cell Biology
- Immunology
Background:
- Pigs infected with pseudorabies virus (PRV) exhibit necrotic pathology.
- The precise mechanism of PRV-induced cell death remains unclear.
- Necroptosis, a programmed cell death pathway involving RIPK3 and MLKL, has emerged as a significant biological process.
Purpose of the Study:
- To investigate the role of necroptosis in PRV-induced cell death in pigs.
- To elucidate the molecular mechanisms underlying PRV-mediated pathology.
Main Methods:
- PK-15 cells were infected with PRV.
- Cell death was assessed using Propidium Iodide (PI) staining.
- Transmission electron microscopy was employed to visualize cellular damage.
- Western blotting was used to analyze protein cleavage and phosphorylation.
- Specific inhibitors and shRNA knockdown were utilized to target key necroptosis pathway proteins (RIPK3, MLKL, RIPK1).
Main Results:
- PRV infection induced RIPK3-dependent necroptosis, characterized by PI-positive staining and plasma membrane disruption.
- Caspase-3 and caspase-8 were not cleaved, and a pan-caspase inhibitor did not prevent cell death.
- RIPK1 was not involved, but RIPK3 and MLKL phosphorylation was upregulated.
- Knockdown of RIPK3 or MLKL reduced PRV-induced cell death and increased viral titers.
Conclusions:
- PRV infection initiates RIPK3/MLKL-dependent necroptosis in host cells.
- Host cell necroptosis plays a crucial limiting role in PRV infection.
- Targeting necroptosis may offer a novel strategy for managing PRV in pigs.
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