Developmental changes in expression of the Drosophila melanogaster epidermal growth factor receptor gene.

A Drosophila gene homologous to the human EGF receptor gene has recently been isolated and sequenced. Two transcripts, 7.6- and 7.1-kb long, encoded by this gene were identified in Drosophila melanogaster. The transcripts are present at low abundance in the maternal RNA stored in unfertilized eggs and in 2-hr-old embryos. The abundance of both transcripts increases sharply between 2 and 5 hr after egg deposition, it remains high throughout embryogenesis, and decreases again in the larval and pupal stages. In adult flies the two transcripts are expressed differentially. The 7.1-kb transcript is present during adulthood at the same level detected previously in pupal stage, but the abundance of the 7.6-kb transcript decreases substantially and it remains low during adulthood.