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Nonlytic Egress and Transmission in the Virus World
Nihal Altan-Bonnet1, Mamata Panigrahi1
1Laboratory of Host-Pathogen Dynamics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA;
Annual Review of Biochemistry
|June 20, 2025
Summary
Most viruses, including animal, plant, archaeal, and bacterial types, utilize nonlytic pathways to exit cells. These nonlytic virus egress strategies offer transmission advantages and immune evasion.
Area of Science:
- Virology
- Cell Biology
- Microbiology
Background:
- Viruses require cellular egress for propagation.
- Historically, viruses were classified as enveloped (non-lytic egress) or nonenveloped (lytic egress).
Purpose of the Study:
- To challenge the traditional classification of viral egress.
- To propose a unified model of nonlytic viral egress across diverse virus types.
Main Methods:
- Review and synthesis of existing literature on viral egress mechanisms.
- Comparative analysis of egress strategies in animal, plant, archaeal, and bacterial viruses.
Main Results:
- Evidence suggests all animal and plant viruses, and many archaeal and bacterial viruses, egress nonlytically.
- Nonlytic egress pathways facilitate cell-to-cell spread or extracellular release within enveloped forms.
- Nonlytic egress provides advantages like controlled infection load and immune evasion.
Conclusions:
- The traditional dichotomy of lytic versus nonlytic egress is an oversimplification.
- Nonlytic egress is a conserved and advantageous strategy across a broad spectrum of viruses.
- Understanding nonlytic egress is crucial for developing effective antiviral therapies.
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