Tracking adenovirus genomes identifies morphologically distinct late DNA replication compartments.

Area of Science:

• Virology
• Cell Biology
• Molecular Biology

Background:

• Adenoviral virions contain genomes organized into chromatin-like structures by viral core proteins.
• Viral DNA replication, chromatinization, and packaging into progeny virions occur within infected cells.
• The spatiotemporal regulation of viral genomes during these late stages is not fully understood.

Purpose of the Study:

• To investigate the fate of adenoviral genomes and track newly replicated viral DNA and associated factors.
• To elucidate the dynamic changes in viral DNA organization during the late phases of adenovirus infection.

Main Methods:

• Advanced imaging analyses were employed to visualize viral DNA and replication factors.
• A nucleoside analogue was used to track newly synthesized viral DNA.
• Immunofluorescence and co-immunoprecipitation were used to identify protein associations.

Main Results:

• A novel subnuclear domain, the Virus-induced Post-Replication (ViPR) body, was identified, forming after initial replication centers disappear.
• Viral DNA synthesis continues in peripheral compartments that feed into the ViPR bodies.
• The nucleolar protein Mybbp1a was identified as a specific marker for ViPR bodies, associating with viral core protein VII.

Conclusions:

• Adenovirus infection induces the formation of specialized compartments for late-stage viral DNA replication and accumulation.
• ViPR bodies represent a previously uncharacterized structure crucial for progeny viral genome production and organization.
• Mybbp1a serves as a key molecular marker for these late-phase viral DNA replication compartments.