Proximal-distal pattern formation in Drosophila: graded requirement for Distal-less gene activity during limb development

Abstract

The development of all of the adult limbs in Drosophila depends upon the activity of the Distal-less gene. We report here the phenotypic characterization of a number of hypomorphic Distal-less alleles which indicates that there is a graded requirement for Distal-less activity in the developing limbs. Previous analysis of genetically mosaic animals indicated that cells in the early primordia of the limb imaginal dises possess a graded proximal-distal positional information which depends on the presence of the Distal-less gene for its expression. Taken together these data suggest that Distal-less may directly encode the graded positional information that is required to organise the proximal-distal axis of the developing limbs. © 1989 Springer-Verlag.