[Cloning, expression, and regulation of tissue-specific genes in Drosophila].

The family of esterase genes was studied in various Drosophila species. These genes are classified into tissue-specific and housekeeping ones. The expression of tissue-specific esterases in the male reproductive system of Drosophila species from the virilis and melanogaster groups was thoroughly examined. Modifier genes controlling activity level, time of synthesis, and distribution in cells of the tissue-specific esterase isozyme from the ejaculatory bulb were revealed. The structural gene coding for this enzyme was isolated, cloned, and sequenced. This gene was shown to be similar in different Drosophila species; the transcriptional level of tissue specificity of this gene was determined. The possibility of transforming the tissue-specific gene into a housekeeping one was demonstrated. In different Drosophila species, this gene can be expressed in different parts of the reproductive system. In transgenic males carrying the gene of another species the foreign gene is expressed as in the donor.