Fig. 6

A, B Evaluation of the proportions (A) and of the proliferation activity of spermatogonia (B) in zebrafish testes cultured for 4 days in the absence or presence of the Pparg antagonist T0070907 (10 μM). C Area occupied by different types of spermatogonia in wild-type (pparg^+/+) and pparg knockout (pparg^−/−) adult testes. Two different pparg^-/- mutants (alleles 1220 and 1737) were evaluated. D In vivo pparg expression levels in wild-type (insl3^+/+) and insl3 knockout (insl3^-/-) testes 9 and 12 months post-fertilization (left panel), and in control, germ cell-depleted (by exposure to the cytostatic agent busulfan⁵¹), and testes with recovering (from busulfan) spermatogenesis, as described by Crespo et al.²⁵ (NCBI GEO data set GSE116611) (right panel). In A–C and right panel in D, data are shown as mean ± SEM (A, B: N = 6; C: pparg^+/+, pparg^{−/− sa1220} and pparg^{−/− sa1737}, N = 2, 3 and 4; D: N = 5; *p < 0.05; **p < 0.01), and in the left panel in D as mean fold change ± SEM (insl3^+/+ and insl3^−/−, 9 months: N = 8 and 7; insl3^+/+ and insl3^−/−, 12 months: N = 6 and 10; *p < 0.05; **p < 0.01) and expressed relative to the control group (which is set at 1). In C, different letters indicate significant differences between groups (*p < 0.05). A_und, type A undifferentiated spermatogonia; A_diff, type A differentiating spermatogonia; B, type B spermatogonia.