Figure 4.

IFN-α Induces Spindle Pole Misorientation and Decreased PCNT at the Spindle Poles

(A) A549 cells were transfected with either a non-targeting negative control siRNA (NT) or an siRNA targeting the IFN-α receptor, IFNAR1 (IFNAR). Forty eight hours post-transfection the cells were incubated without or with IFN-α (+, 100 IU/mL) for 24 h, then either mock infected (mock) or infected with ZIKV (PRVABC59 MOI 5) for 24 h, and immunostained for PCNT (pink), α-Tub (green), or ZIKV (gray) and stained for DNA (blue). Scale bars for all images, 10 μm.

(B) Spindle pole angle quantification for ZIKV infections or IFN-α addition to A549 cells treated with siRNA(NT) in mock infection (red, 16 A549 cells quantitated), 24 hpi (green, 16 cells), IFN-α treatment (blue, 15 cells), and IFN-α + 24 hpi (orange, 16 cells); siRNA(IFNAR) mock infection (solid red, 16 cells), 24 hpi (solid green, 13 cells), IFN-α treatment (solid blue, 16 cells), and IFN-α + 24 hpi (solid orange, 16 cells).

(C) Quantification of normalized PCNT intensity at the spindle poles for A549 cells analyzed in (A and B). Statistical significance (p value) of the angle changed or integrated intensity between mock and a condition in all quantified data is represented using asterisks above the data; ****p < 0.0001, ***p < 0.001, **p < 0.01. All data represent the mean ± SEM from three independent experiments.