Figure 4.

ptc2 is expressed in progenitor/stem cell populations of the juvenile zebrafish retina. In situ hybridization for the ptc2 transcript in 6-week-old juvenile wild-type retinas. Staining was absent throughout the retina when hybridization was performed using a ptc2 sense control probe (A). (B) ptc2 expression was detected in a population of cells in the INL (C; High magnification of the black box) and in the retinal margin (D; high magnification of white box), where CMZ progenitors reside. qRT-PCR analysis of ptc2 expression from FACS-sorted GFP⁺ Müller glia cells isolated from a gfap:GFP transgenic line revealed enrichment of the ptc2 transcript in GFP⁺ Müller glia when compared to GFP⁻, non-Müller glial cells (E, *P < 0.01, n = 3). GFP⁺ cells were enriched for the Müller glial markers gfap (***P < 0.01, n = 3) and glutamine synthetase (**P < 0.001, n = 3), and GFP⁻ cells were enriched for the neuronal markers huc (*P < 0.01, n = 3) and rhodopsin (***P < 0.0001, n = 3) (F). Scale bars: (A, B) 100 μm; (C) 50 μm; (D) 25 μm.