Oncornavirus precursor particles and the microtubule organizing centers

Area of Science:

• Cell Biology
• Virology
• Microscopy

Background:

• Intracytoplasmic type A particles are precursors to type B retroviruses.
• The role of cellular structures in retroviral particle transport is not fully understood.

Purpose of the Study:

• To investigate the relationship between type A particles and the mitotic apparatus.
• To elucidate the mechanism of type A particle migration during mitotic arrest.

Main Methods:

• Electron microscopy was used to examine hamster and murine cell lines.
• Cells were subjected to mitotic arrest using Colcemid and vincristine sulfate.

Main Results:

• Type A particle migration to chromosome kinetochores occurred during early metaphase arrest.
• This migration was linked to inhibited microtubule formation and spindle fiber attachment.
• Particle association with the mitotic apparatus was reversible upon inhibitor removal and microtubule reformation.

Conclusions:

• Microtubules and cytoskeletal proteins likely play an active role in type B oncornavirus transport and maturation.
• Findings suggest potential epigenetic transmission of these viruses and induction of the transformed state.