Dorsal wing, a locus that affects dorsoventral wing patterning in Drosophila

Area of Science:

• Developmental biology
• Genetics
• Molecular biology

Background:

• The wing imaginal disc in Drosophila melanogaster is crucial for adult wing development.
• Compartment specification, particularly dorsal-ventral patterning, is essential for proper wing formation.
• Homeotic mutations can alter segment identity, providing insights into developmental gene regulation.

Purpose of the Study:

• To characterize a novel dominant homeotic mutation, Dorsal wing1 (Dlw1).
• To investigate the interaction of Dlw1 with known developmental genes, specifically those in the Polycomb (Pc) and trithorax (trx) groups.
• To elucidate the roles of Dlw+ and its regulators in dorsal compartment specification.

Main Methods:

• Analysis of a new dominant homeotic mutation, Dorsal wing1 (Dlw1).
• Phenotypic analysis of Dlw1 heterozygotes and homozygotes.
• Generation and analysis of Dlw1/Dlw1 somatic clones.
• Study of double mutant interactions between Dlw1 and Polycomb (Pc) or trithorax (trx) group mutants.

Main Results:

• Dlw1 heterozygotes exhibit a ventral-to-dorsal compartment transformation, mimicking Pc mutant phenotypes.
• Dlw1/Dlw1 somatic clones differentiate only ventral patterns, similar to trx lethal phenotypes.
• Double mutants (Pc Dlw+/Pc+ Dlw1) show enhanced transformation, while Pc Dlw/Dlw clones exhibit dorsal-to-ventral transformation.
• Dlw1/Dlw1 clones induce extra macrochaetes in the dorsal notum.

Conclusions:

• Dorsal wing1 (Dlw+) is essential for specifying the dorsal compartment of the wing imaginal disc.
• Polycomb group genes act as negative regulators of Dlw+ activity.
• Trithorax group genes function as positive regulators of Dlw+ activity, highlighting a complex regulatory network in wing patterning.