SNARE Protein Mimicry by an Intracellular Bacterium
Figure 2
Several host SNARE proteins are specifically recruited around the inclusion membrane.
A, Localization of endogenous SNAREs in HeLa cells infected for 24 h with C. trachomatis serovar D was assessed using specific antibodies. Vamp3 and Vamp7 encircle the inclusion (arrows), while Sec22 does not (arrowheads). SNAREs are shown on the left, host and bacterial DNA in the second column, and merged images in the third column. Distribution of the SNAREs in uninfected cells is shown on the right. B, Cells were transfected with different GFP-SNARE constructs 8 h before infection. The inclusion was labelled with anti-IncA antibodies followed with TRITC-coupled secondary antibodies. GFP-Vamp8 or GFP-Vamp7 encircle the inclusion membrane (arrows), while GFP, GFP-Vamp4 or GFP-Vamp7 deleted from its SNARE domain (GFP-Longin) do not (arrowheads). GFP-tagged SNAREs are shown on the left, IncA in the second column, and merged images in the third column. Distribution of the SNAREs in uninfected cells is shown on the right. C, Quantification of SNARE recruitment to the inclusion. Cells were scored as positive when the entire circumference of the inclusion was surrounded by the SNARE protein. Means and standard deviations of at least two independent experiments are shown.