Figure 4.

The maturation of Borrelia-containing phagosomes. The nascent phagosome makes contact with the ER and is subsequently pinched off from the plasma membrane. During its maturation into a phagolysosome, the compartment comes into contact with different subpopulations of vesicles, which regulate compaction and acidification. This is accompanied by changes in the composition of the phagosomal membrane and also by respective enrichments of different RabGTPases during specific stages. Molecular regulators with documented roles in Borrelia phagosome maturation are shown in green, while those that have only been detected, but have unknown roles, are shown in orange. Central regulators of phagosome maturation for other pathogens, with likely but still unproven roles in borreliae phagosome processing, are shown in red.