Fig. 5: DmxA is essential for the symmetric incorporation and allocation of the core T4PM proteins at the nascent and new cell poles.

a PilQ-sfGFP localization during the cell cycle. Left panels, epifluorescence and phase-contrast images from time-lapse microscopy of representative WT and ΔdmxA cells. Images were recorded every 30 min; arrowheads indicate completion of cytokinesis. Right panels, quantification of PilQ-sfGFP localization pattern based on time-lapse microscopy. PilQ-sfGFP polar fluorescence was analysed before and after division in the predivisional cell (gray) and the daughters (yellow and pink) and the asymmetry index (ω) calculated as indicated; the pole with the highest fluorescence is defined as Pole 1. Daughter cells are sorted based on their ω with the most symmetric in yellow and the other in pink. Line and error bars, mean ± SD from three biological replicates, number of cell division events per replicate in brackets. Schematics show dominant localization patterns of PilQ-sfGFP in WT and ΔdmxA cells during the cell cycle. b Localization of PilQ-sfGFP, mCherry-PilM, mCherry-PilT and PilB-mCherry in WT and ΔdmxA cells. Left panels, representative snapshot images. Scale bar, 5 μm. Middle panels, histograms of the distribution of the fraction of total cellular fluorescence in polar clusters at pole 1 and pole 2 in WT (gray) and ΔdmxA (blue) cells. The pole with the highest fluorescence is defined as Pole 1. Numbers in the upper right corners indicate the median±MAD fluorescence signal at pole 1 (P1) and pole 2 (P2). The fraction of cells with no polar signal(s) is indicated in the leftmost column labeled d (for diffused) in green; cells in which no polar cluster was detected at pole 1 also do not have a signal at pole 2. Right panels, histograms of the distribution of ω. Localization patterns are binned as unipolar, asymmetric, and symmetric from the ω values as indicated; cells in which no polar signal was detected were not considered in the analysis. Error bars indicate median ± MAD. Differently colored circles indicate the median of each of the three biological replicates. The total number of analysed cells is indicated below. Samples were analysed using the two-sided Mann–Whitney test. Source data are provided as a Source Data file.