A theoretical model for the dynamic structure of hepatitis B nucleocapsid

Area of Science:

• Structural Biology
• Virology
• Computational Biophysics

Background:

• The hepatitis B virus (HBV) capsid protein's C-terminal domain (CTD) is crucial for viral RNA packaging and reverse transcription.
• The precise microscopic structure and dynamic interactions of the CTD with nucleic acids during viral maturation are not well understood.

Purpose of the Study:

• To theoretically analyze the radial distribution of CTD chains and nucleic acids within the HBV nucleocapsid.
• To investigate CTD behavior at the beginning and end stages of viral reverse transcription.

Main Methods:

• Classical density functional theory was employed.
• A coarse-grained model for biomolecules was utilized for theoretical analysis.
• Radial distributions of CTD and nucleic acids were calculated for immature and mature nucleocapsids.

Main Results:

• A significant portion of the CTD is exposed on the surface of RNA-containing immature nucleocapsids.
• The CTD is predominantly confined within the DNA-containing mature nucleocapsids.
• Substantial accumulation of cations is predicted within both immature and mature nucleocapsids.

Conclusions:

• The study provides new insights into the molecular mechanisms by which the CTD regulates viral reverse transcription.
• Findings elucidate the role of CTD structural changes and cation accumulation in nucleocapsid trafficking during HBV replication.