Fig. 3.

A twofold shift in the Pnt/Yan ratio accompanies R cell fate transitions. (A) The log₂-transformed Pnt/Yan ratio in individual progenitor (gray, 7393 cells) and R7 (purple, 544 cells) cells, and their moving line averages (solid black lines). Cells marked as ‘Young R7s’ are the initial cohort of R7 cells that are present in the timespan of the first ten identifiable R7 cells (‘young’ R7s become ‘mature’ Elav-positive R7s in about 2 h). (B) Line averages, with 95% confidence intervals shaded, of the log₂-transformed Pnt/Yan ratio for all annotated cell types over time. N is number of cells sampled. (C-G) Joint distributions of Pnt-GFP and Yan levels in young R7 (C), young R8 (D), young R2/R5 (E), young R3/R4 (F) and young R1/R6 (G) cells. Progenitor cells (gray) present in the timespan of the young R cells were analyzed for comparison. Black lines indicate median Pnt/Yan ratios among progenitor cells. Histograms of the data at the top and side of each scatterplot highlight the overlap between R cells and some of the concurrent progenitors. (H) Comparison of the Pnt/Yan ratios in young R cells (colored boxes and whiskers) versus progenitor cells (gray boxes and whiskers) sampled over comparable time-periods. Forty cells were analyzed for each group of young R cells, and 153-487 cells were analyzed for each group of progenitors. Median ratios boxed by the quartile ratios are shown. Whiskers indicate the upper- and lower-most quartile ratios. ****P<0.001, one-tailed Mann–Whitney U-test.