Kelly LE , Martinez-De Luna RI , El-Hodiri HM .

R01 EY015480 NEI NIH HHS

	Figure 1. UCE1 drives transgene expression in the dorsal CMZ. (a). Schematic diagram of the rax genomic locus (top) and the Tg(UCE1,rax:GFP)Hme transgene. (b) Addition of UCE1 to the Tg(rax:GFP)Hme transgene results in expression in the dorsal CMZ but not the ventral CMZ. (c, d) Addition of UCE1 to the X. laevis rax.S promoter drives expression in the dorsal CMZ. (c) The X. laevis Tg(rax.S:GFP)Mjam transgene is not expressed in the CMZ (open arrowheads). (d) Addition of UCE1 to the Tg(rax.S:GFP)Mjam transgene results in expression in the dorsal CMZ (filled arrowhead). Transgene expression was visualized by in situ hybridization using a GFP antisense riboprobe (blue color). L – lens. Sections are oriented so that the dorsal aspect of the embryo is toward the top of the figure.
	Figure 2. Rax can bind to UCE1 in vitro and in vivo. (a) Schematic diagram of UCE1 showing the putative PCE-1 and Nkx sites. (b) Rax can bind the PCE-1 and Nkx sites in vitro. EMSA using an oligonucleotide spanning the UCE1 PCE-1 site as probe and competitor oligonucleotides spanning the same site (lanes 3 and 4), the mouse rhodopsin promoter PCE-1 site (lanes 5 and 6) or the UCE1 Nkx site (lanes 7 and 8). For each competitor we used a wild type version (lanes 3, 5, and 7) or a version in which the PCE-1 site was mutated (lanes 4, 6, and 8). Addition of in vitro translated Rax protein to the probe resulted in two bands of shifted mobility (S1, S2). (c) Rax can bind UCE1 in vivo. ChIP performed using embryos injected with RNA encoding myc-tagged Rax (MT-Rax) and immunoprecipitated using an antibody raised agains the myc tag. UCE1 is specifically precipitated by anti-myc antibody and not control IgG. UCE1 is specifically precipitated but UCE2 is not.
	Figure 3. rax-dependent UCE1 activity is mediated through the PCE-1 site. (a–c) Expression of the Tg(UCE1,rax.S:GFP)Hme transgene containing mutations in the Nkx site (a), PCE-1 site (b), or both (c). (d) Expression of Tg(PCE-1,rax.S:GFP)Hme transgene. Expression is visualized by in situ hybridization of sectioned retinal tissue using a GFP antisense riboprobe. Open arrowheads indicate lack of expression in the CMZ; black arrowhead indicates expression in the CMZ. L – lens. Sections are oriented so that the dorsal aspect of the embryo is toward the top of the figure.

Adamska, Five Nkx5 genes show differential expression patterns in anlagen of sensory organs in medaka: insight into the evolution of the gene family. 2001, Pubmed

Adamska, Five Nkx5 genes show differential expression patterns in anlagen of sensory organs in medaka: insight into the evolution of the gene family. 2001, Pubmed
Bailey, Regulation of vertebrate eye development by Rx genes. 2004, Pubmed , Xenbase
Batni, Characterization of the Xenopus rhodopsin gene. 1996, Pubmed , Xenbase
Boatright, A major cis activator of the IRBP gene contains CRX-binding and Ret-1/PCE-I elements. 1997, Pubmed
Casarosa, Xrx1, a novel Xenopus homeobox gene expressed during eye and pineal gland development. 1997, Pubmed , Xenbase
Chuang, Expression of three Rx homeobox genes in embryonic and adult zebrafish. 1999, Pubmed
Danno, Molecular links among the causative genes for ocular malformation: Otx2 and Sox2 coregulate Rax expression. 2008, Pubmed , Xenbase
Deitcher, Asymmetric expression of a novel homeobox gene in vertebrate sensory organs. 1994, Pubmed
Hocking, Expression of Bmp ligands and receptors in the developing Xenopus retina. 2007, Pubmed , Xenbase
Huang, Metamorphosis is inhibited in transgenic Xenopus laevis tadpoles that overexpress type III deiodinase. 1999, Pubmed , Xenbase
Kelly, Xenopus laevis Nkx5.3 and sensory organ homeobox (SOHo) are expressed in developing sensory organs and ganglia of the head and anterior trunk. 2016, Pubmed , Xenbase
Kelly, Recombineered Xenopus tropicalis BAC expresses a GFP reporter under the control of Arx transcriptional regulatory elements in transgenic Xenopus laevis embryos. 2005, Pubmed , Xenbase
Kikuchi, The proximal promoter of the mouse arrestin gene directs gene expression in photoreceptor cells and contains an evolutionarily conserved retinal factor-binding site. 1993, Pubmed
Kimura, Both PCE-1/RX and OTX/CRX interactions are necessary for photoreceptor-specific gene expression. 2000, Pubmed
Kroll, Transgenic Xenopus embryos from sperm nuclear transplantations reveal FGF signaling requirements during gastrulation. 1996, Pubmed , Xenbase
Ma, Retina-specific cis-elements and binding nuclear proteins of carp rhodopsin gene. 2001, Pubmed
Mani, Xenopus rhodopsin promoter. Identification of immediate upstream sequences necessary for high level, rod-specific transcription. 2001, Pubmed , Xenbase
Marsh-Armstrong, Asymmetric growth and development of the Xenopus laevis retina during metamorphosis is controlled by type III deiodinase. 1999, Pubmed , Xenbase
Martinez-de Luna, Regulation of retinal homeobox gene transcription by cooperative activity among cis-elements. 2010, Pubmed , Xenbase
Mathers, The Rx homeobox gene is essential for vertebrate eye development. 1997, Pubmed , Xenbase
Moritz, Xenopus laevis red cone opsin and Prph2 promoters allow transgene expression in amphibian cones, or both rods and cones. 2002, Pubmed , Xenbase
Pan, The Rx-like homeobox gene (Rx-L) is necessary for normal photoreceptor development. 2006, Pubmed , Xenbase
Pan, Regulation of photoreceptor gene expression by the retinal homeobox (Rx) gene product. 2010, Pubmed , Xenbase
Shimamura, Wnt-1-dependent regulation of local E-cadherin and alpha N-catenin expression in the embryonic mouse brain. 1994, Pubmed
Sparrow, A simplified method of generating transgenic Xenopus. 2000, Pubmed , Xenbase
Stadler, Characterization of the homeobox-containing gene GH6 identifies novel regions of homeobox gene expression in the developing chick embryo. 1994, Pubmed
Viczian, XOtx5b and XOtx2 regulate photoreceptor and bipolar fates in the Xenopus retina. 2003, Pubmed , Xenbase
Voronina, Mutations in the human RAX homeobox gene in a patient with anophthalmia and sclerocornea. 2004, Pubmed
Wang, The role of combinational coding by homeodomain and bHLH transcription factors in retinal cell fate specification. 2005, Pubmed , Xenbase
Zhang, Targeted expression of the dominant-negative FGFR4a in the eye using Xrx1A regulatory sequences interferes with normal retinal development. 2003, Pubmed , Xenbase
Zuber, Specification of the vertebrate eye by a network of eye field transcription factors. 2003, Pubmed , Xenbase