Question

ASSIGNMENT 1: DROSOPHILA IMAGINAL DISC DEVELOPMENT 1) In Drosophila, the legs, wings and other adult structures develop from imaginal discs. Briefly describe what an imaginal disc is and how it forms an adult structure. 2) Describe the antero-posterior patterning of the dorsal wing imaginal disc, including the major genes involved and their role in this patterning. 3) Describe the antero-posterior, dorso-ventral and proximo-distal patterning of the ventral leg imaginal disc, including the major genes involved and their role in patterning.

Answer 1

1) Imaginal disc is a group of epithelial cells present in the holometabulous larva of the insect which gets transformed into outside parts of the insect body like legs , wings etc during pupal transformation (metamorphosis).

During pupal stage, many larval structures are destroyed to form the adult structure through a rapid development. Each imaginal disc everts and gets elongated with the central part resembling whichever appendage is to be formed , it may be wings or legs etc. During larval period , these discs are undifferentiated which gets transformed at the pupal stage .