A glimpse into dorso-ventral patterning of the Drosophila eye

Department of Biology, University of Dayton, Dayton, Ohio 45469, USA.
Developmental Dynamics (Impact Factor: 2.67). 01/2012; 241(1):69-84. DOI: 10.1002/dvdy.22764
Source: PubMed

ABSTRACT During organogenesis in all multi-cellular organisms, axial patterning is required to transform a single layer organ primordium into a three-dimensional organ. The Drosophila eye model serves as an excellent model to study axial patterning. Dorso-ventral (DV) axis determination is the first lineage restriction event during axial patterning of the Drosophila eye. The early Drosophila eye primordium has a default ventral fate, and the dorsal eye fate is established by onset of dorsal selector gene pannier (pnr) expression in a group of cells on the dorsal eye margin. The boundary between dorsal and ventral compartments called the equator is the site for Notch (N) activation, which triggers cell proliferation and differentiation. This review will focus on (1) chronology of events during DV axis determination; (2) how early division of eye into dorsal and ventral compartments contributes towards the growth and patterning of the fly retina, and (3) functions of DV patterning genes.

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Available from: Amit Singh, Aug 21, 2015
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    • "Most of these strategies provide excellent tools for generation of clones in the entire developing eye field. During organogenesis, a developing field gets further subdivided into smaller regions called compartments (Blair, 2001; Curtiss et al., 2002; Dahmann et al., 2011; Singh et al., 2012). The properties of the cells of a compartment are unique and the cells within a compartment behave differently based on their response to the morphogen gradients. "
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    ABSTRACT: Genetic mosaic approach is commonly employed in the Drosophila eye by completely abolishing or misexpressing a gene within a subset of cells to unravel its role during development. Classical genetic mosaic approach involves random clone generation in all developing fields. Consequently, a large sample size needs to be screened to generate and analyze clones in specific domains of the developing eye. To address domain specific functions of genes during axial patterning, we have developed a system for generating mosaic clones by combining Gal4/UAS and FLP/FRT system which will allow generation of loss-of-function as well as gain-of-function clones on the dorsal and ventral eye margins. We used the bifid-Gal4 driver to drive expression of UAS-flippase (FLP). This reagent can have multiple applications in (i) studying spatio-temporal function of a gene during dorso-ventral axis specification in the eye, (ii) analyzing genetic epistasis of genes involved in DV patterning and (iii) conducting genome wide screens in a domain specific manner. © 2012 Wiley Periodicals, Inc.
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    ABSTRACT: Organ formation requires a delicate balance of positive and negative regulators. In Drosophila eye development, wingless (wg) is expressed at the lateral margins of the eye disc and serves to block retinal development. The T-box gene optomotor-blind (omb) is expressed in a similar pattern and is regulated by Wg. Omb mediates part of Wg activity in blocking eye development. Omb exerts its function primarily by blocking cell proliferation. These effects occur predominantly in the ventral margin. Our results suggest that the primary effect of Omb is the blocking of Jak/STAT signaling by repressing transcription of upd which encodes the Jak receptor ligand Unpaired.
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    Encyclopedia of Life Sciences, 03/2013: chapter Drosophila Eye Development and Photoreceptor Specification; John Wiley & Sons.
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