Abstract
The Drosophila genome was screened for DNA sequences that have homology with the mouse alpha-interferon gene MuIFN alpha 2, by hybridizing a library of cloned Drosophila genomic DNA with an MuIFN alpha 2 cDNA probe under reduced stringency conditions. Several dispersed regions of homology were identified, one of which was mapped at position 67D8-10 on chromosome 3. The homology in this region occurs within a gene, called ect, which encodes a 2.9-kb poly(A)+RNA transcript. The principal homology between ect and MuIFN alpha 2 involves A + T-rich sequences with short repeats, which are located within the untranslated 3' end of the transcribed region of each gene. Since no homology between the translated regions of ect and MuIFN alpha 2 was detected by hybridization, there appears to be no significant structural or functional homology between the encoded proteins. The ect gene is temporally regulated during Drosophila development, with a major peak of expression during the second half of Drosophila embryogenesis. Expression of ect occurs selectively in ectodermal tissues of the embryo, suggesting a specialized role for the gene in the early development of ectodermal structures.
