IN-VIVO REGULATION OF TISSUE-SPECIFIC AND LPS-INDUCIBLE EXPRESSION OFTHE DROSOPHILA CECROPIN GENES

The inducible production of antibacterial cecropins in Drosophila fat body and haemocytes is controlled at the level of transcriptional indu ction. We demonstrate using germ-line transformation that a short, hig hly conserved, DNA region, including the insect kappa B motif, is nece ssary for tissue-specific expression in larvae and adults. Quantitativ e measurements of reporter gene activity in extracts from transgenic l arvae confirmed the requirement of this proximal region for LPS-induci ble expression in vivo. Transient expression in a blood cell line indi cates the existence of positively acting elements further upstream of the conserved region. Furthermore, our in vivo data suggests that the distal upstream region contains negatively acting element(s).