Fig. 4.

An artificial increase in the Pnt/Yan ratio biases progenitor cells towards an R fate. (A) Schematic showing the effect of Ras^V12 on signal transduction and Yan and Pnt expression in eye cells. (B-D) Line averages, with 95% confidence intervals shaded, of Pnt-GFP (B), Yan (C) and log₂-transformed ratio of Pnt/Yan ratio (C) in wild-type (black) and sev>Ras^V12 (red) progenitor cells over developmental time. Red arrows indicate the time during which cells express Ras^V12. We have previously reported a modest increase in the duration of Yan-YFP expression in sev>Ras^V12 progenitor cells (Peláez et al., 2015), but this difference was not detected using the Yan antibody (B). 1381 (wild type) and 4038 (sev>Ras^V12) progenitors were analyzed. (E) The log₂-transformed ratio of Pnt/Yan in wild-type and sev>Ras^V12 young R7 cells (purple). Progenitor cells (gray) present in the same timespan were also analyzed. In sev>Ras^V12 eye discs, there were ectopic R7 cells (blue). Box plots show the median (horizontal line) and quartiles (upper and lower edges of the box). Whiskers indicate the upper- and lower-most quartile ratios. N is the number of cells analyzed in each group.