Fig. 1

Expression of BMAL1 and ontogenesis of PER2::Luc circadian oscillations in wild-type and Opn4 ^−/− retinal explants. A Immunostaining of BMAL1 (red) in retinal sections of wild-type mice counterstained with DAPI (blue) at P3, P5 and P8. Scale bar = 10 µm: NBL, neuroblastic retina; ONL, outer nuclear layer; INL, inner nuclear layer and GCL, ganglion cell layer. B Representative bioluminescence recording of PER2::Luc retinal explants from Per2 ^Luc (black line) and Opn4 ^−/− ::Per2 ^Luc (blue line) mice at different postnatal stages (P5, P8, P11, P15, P30) and in the adult. Retinal explants were cultured for at least 6 days without medium change. The dotted black rectangle corresponds to an enlargement of bioluminescence traces of both genotypes at P5. C Means of the endogenous period, the circadian phase, and the amplitude in both genotypes during development. The total numbers of retinas used were respectively for wild-type mice: P8, n = 10; P11, n = 10; P15, n = 6; P30, n = 8; adult, n = 10 and for Opn4 ^−/− ::Per2 ^Luc; P8, n = 6; P11, n = 6; P15, n = 7; P30, n = 6 and adult, n = 10. Bars represent the mean ± SEM (ANOVA, ** = p ≤ 0.01; *** = p ≤ 0.001)