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Updated: Jul 31, 2026

Preparation of Adult Drosophila Eyes for Thin Sectioning and Microscopic Analysis
Published on: August 27, 2011
The Iroquois homeobox genes function as dorsal selectors in the Drosophila head
F Cavodeassi1, J Modolell, S Campuzano
1Centro de Biología Molecular Severo Ochoa, CSIC and UAM Cantoblanco, Spain.
Abstract:
The Iroquois complex (Iro-C) genes are expressed in the dorsal compartment of the Drosophila eye/antenna imaginal disc. Previous work has shown that the Iro-C homeoproteins are essential for establishing a dorsoventral pattern organizing center necessary for eye development. Here we show that, in addition, the Iro-C products are required for the specification of dorsal head structures. In mosaic animals, the removal of the Iro-C transforms the dorsal head capsule into ventral structures, namely, ptilinum, prefrons and suborbital bristles. Moreover, the Iro-C(-) cells can give rise to an ectopic antenna and maxillary palpus, the main derivatives of the antenna part of the imaginal disc. These transformations are cell-autonomous, which indicates that the descendants of a dorsal Iro-C(-) cell can give rise to essentially all the ventral derivatives of the eye/antenna disc. These results support a role of the Iro-C as a dorsal selector in the eye and head capsule. Moreover, they reinforce the idea that developmental cues inherited from the distinct embryonic segments from which the eye/antenna disc originates play a minimal role in the patterning of this disc.
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