Membraneless Organelles and Condensates Orchestrate Innate Immunity Against Viruses

Area of Science:

• Cellular and Molecular Immunology
• Virology
• Biochemistry

Background:

• Cellular defense against viruses relies on membraneless organelles (MLOs) and innate immune signaling.
• Pattern recognition receptors (PRRs) initiate immune responses through phase-separation and condensate formation.
• Key condensates include inflammasomes, ASC specks, cGAS foci, PKR clusters, RLBs, SGs, PBs, and PML NBs.

Purpose of the Study:

• To review mechanisms by which viruses evade host innate immunity.
• To explore viral strategies targeting the formation and function of immune-related condensates.
• To summarize interconnections between condensates in determining cellular outcomes during viral infection.

Main Methods:

• Literature review of current and hypothetical mechanisms.
• Analysis of viral strategies interfering with condensate dynamics.
• Synthesis of information on condensate roles in innate immunity and viral evasion.

Main Results:

• Viruses employ diverse strategies to disrupt host defense condensates.
• Viral components like nucleic acids, proteases, or disordered proteins interfere with condensate assembly and function.
• Mechanisms include disassembly, repurposing, or inactivation of crucial immune condensates.

Conclusions:

• Understanding viral evasion of condensate-mediated immunity is crucial for developing antiviral strategies.
• Interplay between different condensates dictates the cellular response to viral infection.
• Targeting viral interference with MLOs offers potential therapeutic avenues.