Sept15 morphants show increased susceptibility to S. flexneri infection.
A. Representative western blot of extracts from larvae injected with control (Ctrl) or Sept15 morpholino (Mo) using antibodies against GAPDH (as control) or SEPT7. B. Survival curves of Ctrl or Sept15 morphants infected with S. flexneri M90T (low dose). Pooled data from 3 independent experiments per treatment using at least 15 larvae per treatment. Significance testing performed by Log Rank test. **, P<0.01. C. Enumeration of bacteria at 0, 24, or 48 hpi from Ctrl (open circles) or Sept15 (closed circles) morphants infected with S. flexneri M90T (low dose). Half-filled circles represent enumerations from larvae at time 0 and are representative of inoculums for both conditions. Pooled data from 3 independent experiments using up to 3 larvae per treatment. Circles represent individual larvae, and only larvae having survived the infection (thus far) included here (i.e., dead larvae not homogenised for counts). Mean ± SEM also shown (horizontal bars). Significance testing performed by Student’s t test. *, P<0.05; ***, P<0.001. D. Representative images of larvae injected with Ctrl or Sept15 Mo and infected in the HBV with GFP-S. flexneri M90T (low dose). For each treatment, the same larva was imaged at 0, 24, and 48 hpi using a fluorescent stereomicroscope. Scale bars, 100 μm. See also S4 and S5 Videos. E-F. Representative frames extracted from in vivo time-lapse confocal imaging of lyz:dsRed larvae (3 dpf, red neutrophils) injected with (E) Ctrl or (F) Sept15 Mo and infected in the HBV with GFP-S. flexneri M90T (low dose). First frame 20 mpi, followed by frames at 6, 15, and 20 hpi. Maximum intensity Z-projection images (2 μm serial optical sections) are shown. Scale bars, 50 μm. See also S6 and S7 Videos.