Contrasting roles of autophagy in cellular prion infection

Area of Science:

• Cell Biology
• Neuroscience
• Molecular Biology

Background:

• Autophagy is a fundamental cellular process involved in degrading damaged organelles and proteins.
• Dysregulation of autophagy is implicated in various neurodegenerative diseases, including prion diseases.
• The precise role of autophagy in the prion life cycle remains incompletely understood.

Purpose of the Study:

• To investigate the role of macroautophagy/autophagy in prion infection.
• To determine how autophagy influences the life cycle and propagation of prions.
• To elucidate the context-dependent functions of autophagy in prion pathogenesis.

Main Methods:

• Utilized gene editing to ablate autophagy competence in neuronal cells.
• Examined prion replication and prion protein levels in mouse embryonic fibroblasts and neuronal cells.
• Analyzed the impact of autophagy on prion propagation and degradation.

Main Results:

• Prion replication in mouse embryonic fibroblasts showed a strong dependence on autophagy competence, indicating support for prion propagation.
• In contrast, neuronal cells lacking autophagy exhibited increased levels of misfolded prion protein, suggesting autophagy mediates prion degradation.
• Autophagy demonstrated opposing functions in prion infection, acting as a supportive mechanism in some cells and a defense mechanism in others.

Conclusions:

• Autophagy plays a context-dependent role in prion infection, influencing both prion propagation and degradation.
• Prions exploit cellular machinery for propagation in certain cell types.
• Neuronal cells utilize autophagy as a defense mechanism against prion accumulation.