Related Experiment Videos
Drosophila terminalia as an appendage-like structure.
N Gorfinkiel1, L Sánchez, I Guerrero
1Centro de Biologia Molecular 'Severo Ochoa' Universidad Autonoma de Madrid, Cantoblanco, E-28049, Madrid, Spain.
Mechanisms of Development
|August 14, 1999
Summary
Distal-less (Dll) gene activity is essential for fruit fly terminalia development, regulating analia formation and repressing hindgut development. This highlights conserved mechanisms in appendage evolution.
Area of Science:
- Developmental Biology
- Genetics
- Evolutionary Biology
Background:
- Homeotic gene Distal-less (Dll) establishes ventral appendage identity in Drosophila.
- The genital disc's role in terminalia development is incompletely understood.
Purpose of the Study:
- To investigate Dll expression and function in the Drosophila genital disc.
- To elucidate Dll's role in terminalia development and its regulation by Wingless (Wg) and Decapentaplegic (Dpp).
Main Methods:
- Analysis of Dll expression patterns in the genital disc.
- Functional studies involving loss-of-function and ectopic expression of Dll.
- Examination of gene interactions, including hedgehog (hh) and optomotor-blind (omb).
Main Results:
- Dll is expressed in the genital disc and is required for terminalia development.
- Dll activity is activated by Wg and Dpp signaling.
- Dll functions in analia development but not hindgut development, with loss of Dll leading to hindgut transformation.
- Dll is required for both male anal plates and the female dorsal anal plate, supporting a two-primordia model for analia.
- Dll acts upstream of optomotor-blind (omb), downstream of Dpp.
Conclusions:
- The terminalia share developmental similarities with other ventral appendages like legs and antennae.
- These findings support the ventral origin hypothesis for the genital disc.
- Terminalia can be considered evolutionarily ancestral appendages.