Patterns of protein synthesis in the imaginal discs of Drosophila melanogaster: a comparison between different discs and stages.

High-resolution two dimensional gel electrophoresis has been used to study the patterns of protein synthesis in imaginal discs of Drosophila melanogaster. In this paper we first compare the patterns of protein synthesis in wing, haltere, leg 1, leg 2, leg 3 and eye antenna imaginal discs of late third instar larvae. We have detected only quantitative changes: differences in 17 proteins among the different imaginal discs. In addition, we have analysed the variations in pattern of proteins in the wing disc of the last larval stage and early pupae as well as in wing discs cultured in vivo for 6 days. Variations in these patterns affect more than 20% of the proteins and involve both qualitative and quantitative changes. Some of the changes may correspond to protein phosphorylation. Correlations of these changes between discs and through development are also discussed.