Fig. 5.

nr2f1b expression is associated with resistance to Notch inhibition.

(A) Confocal images of caudal areas in the dorsal pallium (see Fig. 1B) of fish treated for 48 hours with either DMSO or LY, immunostained for Zo1 (white, apical junctions) and Pcna (red, proliferation) and processed for smFISH for nr2f1b (cyan). Scale bars, 5 μm. (B) Quantification of the proportion of cycling cells as a function of nr2f1b expression after 48 hours of LY treatment. nr2f1b^pos cells are less likely to be cycling than nr2f1b^neg cells. Reported P value is derived from a χ² test. Violin plots are built from bootstrapped random sampling of the measured proportions to estimate the distribution but these estimated distributions are not used for statistical testing. DMSO: n = 3 brains, 1263 cells; LY: n = 3 brains, 1378 cells; nr2f1b^neg cells have zero nr2f1b mRNA dots. (C) Difference in response rate (see definition of response rate in Material and Methods) between nr2f1b^pos and nr2f1b^neg cells highlighting that nr2f1b^pos cells are less likely to respond to Notch inhibition. The histogram represents bootstrapped values to estimate a null distribution of the difference in response rates between nr2f1b^pos and nr2f1b^neg cells via Monte Carlo simulation. The dotted red vertical line represents the observed difference in response rate. Fifty bootstrapped simulations with 1000 samples each were conducted, the P value represented here corresponds to the maximum proportion of simulated values across all 50 bootstraps that were inferior to the observed difference.