[Enveloped Virus Entry as a Pharmacological Target: Viral Membrane Fusion Machineries and Their Inhibitors]

Area of Science:

• Virology
• Structural Biology
• Drug Discovery

Background:

• Enveloped virus entry into host cells is a critical early step in infection.
• Viral fusion glycoproteins mediate this entry process, making them key targets for antiviral strategies.
• Despite structural diversity, viral fusion glycoproteins share functional similarities, including distinct domains for receptor binding and membrane fusion.

Purpose of the Study:

• To describe the membrane fusion machinery of all three classes of viral fusion glycoproteins.
• To identify specific domains and structures within these glycoproteins that can be targeted by entry inhibitors.
• To provide examples of existing entry inhibitors and discuss future perspectives for broad-acting inhibitors.

Main Methods:

• Review and description of the structural and functional features of viral fusion glycoproteins.
• Analysis of the membrane fusion process mediated by these glycoproteins.
• Categorization and examples of various classes of entry inhibitors.

Main Results:

• Viral fusion glycoproteins, despite different structures, share conserved functional domains essential for membrane fusion.
• Specific structural elements, including fusion peptides/loops and the membrane-proximal external region (MPER), are crucial for fusion.
• Various entry inhibitors targeting different stages of glycoprotein function, such as receptor binding and fusion, have been developed.

Conclusions:

• Targeting viral fusion glycoproteins offers a promising strategy for developing effective antiviral therapies.
• Understanding the detailed mechanisms and structures of viral fusion machinery is key to designing novel entry inhibitors.
• Further research into these targets holds potential for developing broadly acting antiviral agents.