Pathogenic bacteria in action
Listeria monocytogenes cell-to-cell spread
Host cells (A549) expressing a red membrane marker (farnesylated TagRFP-T) are mixed with unlabeled host cells, followed by infection with GFP-expressing L. monocytogenes (from Lamason et al., Cell 2016). Note the long and highly dynamic protrusion extending into the unlabeled recipient cell.
Rickettsia parkeri cell-to-cell spread
Host cells (A549) expressing a red membrane marker (farnesylated TagRFP-T) are mixed with unlabeled host cells, followed by infection with GFP-expressing R. parkeri (from Lamason et al., Cell 2016). Note the short protrusion formed.
Differential requirements for The actin polymerization machinery
L. monocytogenes polymerize actin tails (blue) that help them rocket into the plasma membrane (red) and generate long protrusions into unlabeled neighboring cells (left movie). In contrast, the movie on the right shows how R. parkeri (blue) appear to lose their tails (green) before initiating spread. This results in much shorter protrusions (red) that push into the unlabeled neighboring cell (from Lamason et al., Cell 2016).
R. parkeri vesicle escape
Near the end of this movie (0:11, center of screen) is a very clear example of R. parkeri (green) breaking out of a double-membrane vesicle (red).
