TAF(II)S MEDIATE ACTIVATION OF TRANSCRIPTION IN THE DROSOPHILA EMBRYO

Mutations in the genes for two highly conserved TAFs, TAF(II)60 and TA F(II)110, reduce transcription of Bicoid-dependent target genes in viv o. By means of several distinct genetic test systems, specific activat or-TAF interactions are shown to support both simple and synergistic e nhancement of transcription in the embryo. These studies provide in vi vo evidence that TAFs can serve as coactivators to receive gene-specif ic transcriptional activation signals. This genetic system also presen ts the opportunity to study the function of basal transcription compon ents in regulating development of complex organisms.