Introduction:

• 2,5-OAS is essential for body's defence against viral infections
• Part of immune response triggered by interferon signalling
• Found in epithelial and immune cells
• Important for understanding virus-host defence relationship

The arrangement and functioning of 2,5-OAS:

• Catalyses synthesis of 2',5'-linked oligoadenylates from ATP
• Activated by double-stranded RNA (dsRNA) from viral replication
• Contains three main domains:
• N-terminal oligomerisation domain
• Middle catalytic domain
• C-terminal dsRNA binding domain
• Structure changes upon dsRNA binding to increase efficiency

Exploring the Function in Fighting Viral Infections:

• 2-5A molecules act as secondary messengers
• Activates RNase L which breaks down cellular RNA
• Stops viral replication
• Triggers infected cell apoptosis
• Part of interferon-mediated defence system

Controlling the expression of 2,5-OAS:

• Activity increases with type I interferon release
• Part of interferon-stimulated genes (ISGs)
• Regulated through transcriptional and post-transcriptional mechanisms
• Mutations can increase susceptibility to infections
• Important for cellular antiviral defence management

Significance in Clinical Practice and Potential for Treatment:

• Potential biomarker for viral infections
• Indicates host response to viruses
• Important for developing immune-enhancing treatments
• Relevant for managing autoimmune disorders
• Connected to 2,5-OAS/RNase L pathway disorders