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Fig. 5
Sox11 negatively regulates Hedgehog (Hh) signaling.
(A) Transverse retinal sections from 24 hpf ptc2:EGFP zebrafish embryos injected with control or sox11 MO. Sox11 morphants displayed elevated GFP expression in the brain as well as in the central and dorsal retina, and the dorsal RPE (number of embryos analyzed: control MO, n = 8; sox11 MO, n = 10). (B) Treatment with the Hh inhibitor cyclopamine rescued the ocular phenotypes in sox11 morphants. In contrast, treatment with the Hh agonist purmorphamine increased the prevalence of ocular phenotypes in embryos injected with a half dose of sox11 MO. Number of embryos analyzed: 24 hpf sox11MO (plus 100% ethanol), n = 393; 2 dpf sox11 MO (plus 100% ethanol), n = 319; 24 hpf sox11 MO plus cyclopamine, n = 276; 2 dpf sox11 MO plus cyclopamine, n = 263; 24 hpf half dose sox11 MO (plus DMSO), n = 258; 2 dpf sox11 MO half dose (plus DMSO), n = 241; 24 hpf uninjected plus purmorphamine, n = 83; 2 dpf uninjected plus purmorphamine, n = 81; 24 hpf half dose sox11 MO plus purmorphamine, n = 291; 2 dpf half dose sox11 MO plus purmorphamine, n = 270; 3 independent biological replicates. * and # p<0.0001, Fisher′s exact test. (C) Treatment with cyclopamine rescued rod photoreceptor number in sox11 morphants. Rods were counted in retinal cryosections from 3 dpf embryos. Number of embryos analyzed: control MO, n = 17; sox11 MO, n = 20; sox11 MO plus cyclopamine, n = 18; 3 independent replicates. *p = 0.02, Student′s t-test). (D) Overexpression of zebrafish sox11 increased the proportion of embryos with a cyclopic phenotype (right) compared to embryos injected with equimolar amounts of control td-tomato mRNA (left). Number of embryos analyzed: control mRNA, n = 168; sox11 mRNA, n = 202, 3 independent biological replicates.*p<0.001, Fisher′s exact test. D, dorsal; V, ventral; A, anterior; P, posterior; hpf, hours post fertilization; dpf, days post fertilization R, retina; hy, hypothalamus; L, lens; MO, morpholino.