Domina (Dom), a new Drosophila member of the FKH/WH gene family, affects morphogenesis and is a suppressor of position-effect variegation

Domina (Dom) is a novel member of the FKH/WH transcription factor gene fami ly of Drosophila. Two alternatively polyadenylated Dom transcripts of 2.9 a nd 3.9 kb encode a 719-amino-acid protein with a FKH/WH domain and a putati ve acidic transactivation domain. Dorn is mainly expressed in the central a nd peripheral nervous system. Homozygous mutants show rough eyes, irregular arrangement of bristles, extended wings, defective posterior wing margins, and a severely diminished vitality and fertility. Heterozygous Dom flies a re morphologically wild type but show suppression of position-effect varieg ation. Consistently with this chromatin effect DOM protein is accumulated i n the chromocenter and, as expected from a transcription Factor, is found a t specific euchromatic loci. Sequence comparison suggests that DOM of Droso phila is homologous to the chordate WHN proteins. The chromatin modifying c apability of DOM is probably based on the FKH/WH domain, which shows a rema rkable structural similarity to the winged-helix structures of I-ii and the central globular domain of H5. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.