Abstract
In Drosophila, the tracheas defective (tdf) gene encodes a bZIP protein that required for the development of trachea, heart, head and neural system. TDF is highly expressed in the cells of the morphogenetic furrow (MF) region. Loss of TDF function causes defects in the eye development. Overexpression of TDF in the eye disc induced abnormal eyes. Moreover, overexpression of TDF in the leg disc resulted in lack of tarsus. The targets of tdf responsible for these responses have not been identified. To identify tdf downstream genes in a comprehensive manner, we used genome-wide oligonucleotide arrays and analyzed differ-ential gene expression in wild-type embryos versus tdf mutant embryos. Upon knockout of tdf function, expression of 340 genes decreased and 338 genes increased. Many of these genes can be assigned to specific aspects of the tracheal and neural system development. We also discovered tdf target genes that are likely to play specific roles in eye morphogenesis.