Cosuppression in Drosophila: Gene Silencing of Alcohol dehydrogenase by white-Adh Transgenes Is Polycomb Dependent
نویسندگان
چکیده
When two to six copies of a white promoter-Alcohol dehydrogenase (Adh) reporter fusion gene are introduced into the genome, the expression is progressively reduced both in larvae and adults rather than the expected gene dosage effect. In addition, multiple transgenes reduce endogenous Adh transcripts, a result that is strongly analogous to "cosuppression" phenomena described in many plant species but which has not been previously observed in animals. Silencing of the Adh gene is not influenced by zeste-dependent transvection but strongly affected by the Polycomb and Polycomblike mutations. Polycomb and polyhomeotic proteins are bound to the chromatin at the sites of the repressed w-Adh transgenes.
منابع مشابه
Cosuppression of Nonhomologous Transgenes in Drosophila Involves Mutually Related Endogenous Sequences
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عنوان ژورنال:
- Cell
دوره 90 شماره
صفحات -
تاریخ انتشار 1997