A superhighway to virus infection.

Microtubule-mediated transport of macromolecules and organelles (also known as "cargo") is essential for cells to function. Deficiencies in cytoplasmic transport are frequently associated with severe diseases and syndromes. Cytoplasmic transport also provides viruses with the means to reach their site of replication and is the route for newly assembled progeny to leave the infected cell. This parasitic relationship of viruses with the host cytoskeleton provides an excellent basis for cell biologists to unlock the secrets of cytoplasmic transport and unravel mechanisms of disease. Recent advances in live cell imaging and computational tracking of fluorescently labeled viruses are now revealing how complex the movements of single viruses are in infected cells. This review focuses on microtubule-based motility of viruses and highlights the mechanisms regulating cytoplasmic transport.