Fig. 7: Reduced eye progenitor cells in cave planarians.

a Whole animal piwi-1⁺ images show similar distributions of neoblasts between G. dorotocephala and G. multidiverticulata (see also Supplementary Fig. S6e, f for quantification). b G. multidiverticulata has less ovo progenitor cells than G. dorotocephala. c During homeostasis G. multiverticulata (n = 12) has a significantly lower number of eye progenitor cells when compared with G. dorotocephala (n = 14). d FoxA is expressed in the pharynx (dashed blue) and in pharynx progenitors. Red dashed boxes indicate counting region. e During homeostasis G. multiverticulata (n = 10) has a similar number of FoxA⁺ progenitors when compared with G. dorotocephala (n = 13). f FISH expression of agat-3 in late-stage epidermal progenitor cells close to the ventral and dorsal epidermis of G. multidiverticulata and G. dorotocephala, and in the intestine of G. multidiverticulata. g During homeostasis G. multiverticulata (n = 10) has a similar number of agat-3⁺ when compared with the G. dorotocephala (n = 10). h PRN (opsin⁺ cells) loss during 12 days after irradiation. i PRN loss quantification corresponding to cells in (j) is shown. j After normalization, simple linear regression of log-transformed PRN (opsin ⁺ ) numbers show a similar decay (slopes) after irradiation in both cave (n = 22, 18, 31, from 0, 8, and 12 days respectively) and surface planarians (n = 20, 14, 16, from 0, 8 and 12 days respectively) (p = 0.2170). Abbreviations: PRNs, photoreceptor neurons. Scale bars, 50 µm. Mean ± SD. For c, e, g, i, j intervals were compared with a Student’s two-tailed t-test., **p < 0.01 ns, not significant. G. multidiverticulata morphotypes were combined in all the experiments unless otherwise specified. Size-matched animals were used in all experiments.