Originally published as Genetics Published Articles Ahead of Print on September 7, 2009.

Genetics, Vol. 183, 1005-1026, November 2009, Copyright © 2009
doi:10.1534/genetics.109.107748

A Gain-of-Function Screen Identifying Genes Required for Growth and Pattern Formation of the Drosophila melanogaster Wing

Cristina Cruz, Alvaro Glavic1, Mar Casado and Jose F. de Celis2

Centro de Biología Molecular "Severo Ochoa" (CBMSO), Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain

2 Corresponding author: CBMSO, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain.
E-mail: jfdecelis{at}cbm.uam.es

The Drosophila melanogaster wing is a model system for analyzing the genetic control of organ size, shape, and pattern formation. The formation of the wing involves a variety of processes, such as cell growth, proliferation, pattern formation, and differentiation. These developmental processes are under genetic control, and many genes participating in specific aspects of wing development have already being characterized. In this work, we aim to identify novel genes regulating wing growth and patterning. To this end, we have carried out a gain-of-function screen generating novel P-UAS (upstream activating sequences) insertions allowing forced gene expression. We produced 3340 novel P-UAS insertions and isolated 300 that cause a variety of wing phenotypes in combination with a Gal4 driver expressed exclusively in the central domain of the presumptive wing blade. The mapping of these P-UAS insertion sites allowed us to identify the gene that causes the gain-of-function phenotypes. We show that a fraction of these phenotypes are related to the induction of cell death in the domain of ectopic gene expression. Finally, we present a preliminary characterization of a gene identified in the screen, the function of which is required for the development of the L5 longitudinal vein.