Pathogens such as viruses and bacteria must move within infected cells in order to replicate and spread to other cells. Viruses typically hijack the cell’s microtubule cytoskeleton for motility within the cell, while bacteria typically use actin-based mechanisms. Authors of a recent paper have demonstrated how a baculovirus type species uses actin polymerization to first move to the cell’s nucleus, then later move to the cell surface in order to quickly spread to nearby cells. Image above shows an infected cell with the virus (red) translocated to spikes at the cell’s surface. Actin is in green.
Reference: Taro Ohkawa, Loy E. Volkman, and Matthew D. Welch, 2010. Originally published in Journal of Cell Bioloy. doi: 10.1083/jcb.201001162. Paper can be found here.