Aggregation of Influenza A Virus Nuclear Export Protein

Area of Science:

• Virology
• Protein Biochemistry
• Biophysics

Background:

• Influenza A virus nuclear export protein (NEP) is crucial for the viral life cycle.
• Understanding NEP's biophysical properties is key to comprehending viral mechanisms.

Purpose of the Study:

• To investigate the aggregation propensity and properties of recombinant Influenza A virus NEP.
• To identify regions within NEP prone to aggregation and understand the factors influencing this process.

Main Methods:

• Heterologous expression of recombinant NEP (N- and C-terminus His-tagged) in E. coli.
• Dynamic Light Scattering (DLS) to study aggregation kinetics and properties under varying conditions (pH, ionic strength, additives, solvents).
• Atomic Force Microscopy (AFM) to visualize aggregate morphology.
• Structure prediction programs and all-atom molecular dynamics simulations to identify aggregation-prone regions.

Main Results:

• Recombinant NEP proteins exhibit a high propensity for aggregation.
• Spherical aggregates were predominant; amyloid-like structures were observed for NEP-C.
• Aggregation kinetics and properties are influenced by solution conditions.
• Molecular dynamics simulations identified specific regions involved in intermolecular contacts.

Conclusions:

• NEP aggregation is an intrinsic property driven by diverse interactions.
• The aggregation of NEP is likely essential for its in vivo function during the influenza A virus life cycle.