1. RNAi screen for host factors involved in L. monocytogenes dissemination.
RNAi screen for host factors involved in L. monocytogenes dissemination. (A) Images of infection foci in mock-treated (MOCK), and ARPC4-, CAPZB- and AIP1-depleted cells, after 8 hours of infection with GFP-expressing L. monocytogenes (green) and stained with DAPI (red). (B) Quantification of spreading index in cells transfected with four independent siRNA duplexes (labeled A, B, C and D) targeting ARPC4, CAPZB or AIP1. Data are presented as mean±s.e.m. of three independent experiments. The dashed line indicates the threshold corresponding to 2 s.d. units. (C,D) Length of actin tails (C), and proportion of actin-associated bacteria (D) (supplementary material Fig. S2) in the cytosol of cells in which the disassembly components, cofilin-1 (CFL1) and AIP1 have been depleted alone or in combination (Tail length: MOCK vs AIP1, P = 0.0043; MOCK vs CFL1, P = 0.0033; AIP1 versus AIP1+ CFL1, P =  ; CFL1 versus AIP1+CFL1, P = 0.0356; Mann–Whitney U test). (E) Cytosolic velocity of bacteria (MOCK versus AIP1, P = 0.7431; MOCK versus CFL1, P = 0.7791; AIP1 versus AIP1+CFL1, P = 0.2131; CFL1 versus AIP1+CFL1, P = 0.4731; Mann–Whitney U test) (F) Cells were co-transfected with constructs expressing GFP–AIP1 or CFL1–GFP, and infected with CFP-expressing L. monocytogenes. AIP1 and CFL1 are enriched in the cytosolic tail. *P≤0.05; **P≤0.01; ***P≤0.001.
Arthur M. Talman et al. J Cell Sci 2014;127:
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