Publications (2)8.14 Total impact
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Article: Analysis of the Otd-dependent transcriptome supports the evolutionary conservation of CRX/OTX/OTD functions in flies and vertebrates.
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ABSTRACT: Homeobox transcription factors of the vertebrate CRX/OTX family play critical roles in photoreceptor neurons, the rostral brain and circadian processes. In mouse, the three related proteins, CRX, OTX1, and OTX2, fulfill these functions. In Drosophila, the single founding member of this gene family, called orthodenticle (otd), is required during embryonic brain and photoreceptor neuron development. We have used global gene expression analysis in late pupal heads to better characterize the post-embryonic functions of Otd in Drosophila. We have identified 61 genes that are differentially expressed between wild type and a viable eye-specific otd mutant allele. Among them, about one-third represent potentially direct targets of Otd based on their association with evolutionarily conserved Otd-binding sequences. The spectrum of biological functions associated with these gene targets establishes Otd as a critical regulator of photoreceptor morphology and phototransduction, as well as suggests its involvement in circadian processes. Together with the well-documented role of otd in embryonic patterning, this evidence shows that vertebrate and fly genes contribute to analogous biological processes, notwithstanding the significant divergence of the underlying genetic pathways. Our findings underscore the common evolutionary history of photoperception-based functions in vertebrates and invertebrates and support the view that a complex nervous system was already present in the last common ancestor of all bilateria.Developmental Biology 04/2008; 315(2):521-34. · 4.07 Impact Factor -
Article: Partner specificity is essential for proper function of the SIX-type homeodomain proteins Sine oculis and Optix during fly eye development.
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ABSTRACT: The development of the Drosophila visual system utilizes two members of the highly conserved Six-Homeobox family of transcription factor, Sine oculis and Optix. Although in vitro studies have detected differences in DNA-binding and interactions with some co-factors, questions remain as to what extent the activity for these two transcriptional regulators is redundant or specific in vivo. In this work, we show that the SoD mutation within the Six domain does not abolish DNA-protein interactions, but alters co-factor binding specificity to resemble that of Optix. A mutation in the same region of Optix alters its activity in vivo. We propose that the dominant mutant phenotype is primarily due to an alteration in binding properties of the Sine oculis protein and that distinct partner interactions is one important mechanism in determining significant functional differences between these highly conserved factors during eye development.Developmental Biology 11/2005; 286(1):158-68. · 4.07 Impact Factor
