Detailed structure of mouse interferon α2 and its interaction with Sortilin

Area of Science:

• Immunology
• Structural Biology
• Molecular Biology

Background:

• Interferon alpha (IFNα) is a crucial type I interferon cytokine for antiviral defense.
• Limited structural data exists for free IFNα, especially mouse IFNα.
• The precise mechanism of Sortilin-mediated IFNα secretion remains unclear.

Purpose of the Study:

• Determine the crystal structure of mouse IFNα2.
• Investigate the molecular interaction between mouse IFNα2 and Sortilin.
• Elucidate the role of specific residues in Sortilin-mediated IFNα secretion.

Main Methods:

• X-ray crystallography to determine mouse IFNα2 structure.
• Molecular docking simulations to predict interaction sites.
• Site-directed mutagenesis (Arg22 to alanine).
• Flow cytometry to assess IFNα2 secretion.

Main Results:

• The crystal structure of mouse IFNα2 was solved at 2.1 Å resolution.
• Docking simulations identified Arg22 as a potential key residue for Sortilin binding.
• Mutation of Arg22 to alanine significantly enhanced IFNα2 secretion.
• This mutation highlighted Arg22's contribution to Sortilin interaction.

Conclusions:

• Mouse IFNα2 structure provides a basis for understanding its interactions.
• Arg22 is critical for the interaction between mouse IFNα2 and Sortilin.
• This finding clarifies the role of Arg22 in Sortilin-mediated IFNα trafficking and secretion.