Fig 2: ZIKV causes a decrease in fate mapped apical precursor cell number. A, Somatosensory cortex in control and infected brains was transfected with Tbr2-Cre + CAG-StopLight at E13.5 and collected 48 h later (E15.5), labeling the apical progenitors in green and the basal Tbr2 lineage progenitors in red. B, 3 DPI (E15.5) infected tissue with and without (C) IUE show no difference in NS2B labeling. Scale bars: 50 µm. D, ZIKV RT-qPCR in IUE and non-IUE-infected brains across time show no difference in infection. E, Vehicle control electroporated with Tbr2-Cre and CAG-StopLight. Scale bar: 50 µm. F, 3 DPI (E15.5) infected brain electroporated with Tbr2-Cre and CAG-StopLight. Scale bar: 50 µm. G, The percentage of ZsGreen+ cells in the total electroporated population were reduced in infected tissue compared with control (n = 4, 4). Statistical significance was calculated using unpaired t test (*p < 0.05) and error bars represent SE. H, Tbr2-Cre CAG-SL electroporated brains were collected after 48 h (IUE on E12.5). Control and infected brain sections were stained for PH3. The number of PH3+ Tbr2 lineage (mCherry+) cells was decreased by ZIKV infection. I, The number of PH3+ non-Tbr2 lineage (ZsGreen+) cells were decreased by ZIKV infection. E14.5 control and infected brain sections were immunostained for PH3 and Tbr2. J, The number of PH3+, Tbr2+ cells were decreased by ZIKV infection. K, The number of PH3+, Sox2+ cells was substantially decreased by ZIKV infection. Statistical significance was calculated using unpaired t test (*p < 0.05) and error bars represent SE. A sample size of four was used in each condition. L, Tbr2-StopLight fate mapping identifies temporal sequence of cell type infection. Brains were electroporated and co-infected with ZIKV at E12.5 and collected 1–6 DPI. Cell counts from confocal z-stacks indicate that ZsGreen+ apical precursors are preferentially infected at 1 and 2 DPI. At 3 DPI, more mCherry+ basal precursors are infected than apical precursors. Thereafter, infection decreased in both cell types (n = 4, 4). Statistical significance was calculated using unpaired t test (*p < 0.05) and error bars represent SE. M, Immunohistochemical staining for apical (Sox2) and basal (Tbr2) precursors demonstrates temporal spread of infection through the germinal zones. Brains were injected with ZIKV at E12.5 and collected 1–6 DPI. Results indicate that Sox2+ apical precursors are preferentially infected at 1 and 2 DPI. At 3 DPI, more Tbr2+ basal precursors are infected. In later time points, both cell types are infected equally (n = 4, 4). Statistical significance was calculated using unpaired t test (*p < 0.05) and error bars represent SE.