NUBBIN ENCODES A POU-DOMAIN PROTEIN REQUIRED FOR PROXIMAL-DISTAL PATTERNING IN THE DROSOPHILA WING

The nubbin gene is required for normal growth and patterning of the wi ng in Drosophila. We report here that nubbin encodes a member of the P OU family of transcription factors. Regulatory mutants which selective ly remove nubbin expression from wing imaginal discs lead to loss of w ing structures. Although nubbin is expressed throughout the wing primo rdium, analysis of genetic mosaics suggests a localized requirement fo r nubbin activity in the wing hinge. These observations suggest the ex istence of a novel proximal-distal growth control center in the wing h inge, which is required in addition to the well characterized anterior -posterior and dorsal-ventral compartment boundary organizing centers.