A glimpse into dorso-ventral patterning of the Drosophila eye

Department of Biology, University of Dayton, Dayton, Ohio 45469, USA.
Developmental Dynamics (Impact Factor: 2.38). 01/2012; 241(1):69-84. DOI: 10.1002/dvdy.22764
Source: PubMed


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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    • "These cells proliferate during each of the three larval instar stages to form morphologically distinct tissues, then differentiate during pupation in response to the steroid hormone 20-hydroxyecdysone to give rise to the adult appendages and other parts of the head, thorax, and abdomen (Ursprung and Nöthiger 1972). Studies of imaginal disc biology have made significant contributions to axis specification and patterning (Estella et al. 2012; Singh et al. 2012), induction and signal transduction (Ramírez-Weber and Kornberg 2000; Swarup and Verheyen 2012), cell fate specification and differentiation (Furman and Bukharina 2012; Treisman 2013), cell growth and proliferation (Wartlick et al. 2011; Baena-Lopez et al. 2012), cell and tissue polarity (Mlodzik 1999; Müller 2000), and sex determination (Sánchez and Guerrero 2001; Estrada et al. 2003). Research using imaginal discs has also proven fruitful for Copyright © 2015 Smith et al. doi: 10.1534/g3.115.019810 "
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