In Drosophila, broad complex, tramtrack, bric ? brac (BTB)/ poxvirus and zinc finger (POZ) transcription factors are essential regulators of development. We searched the Drosophila genome for BTB/POZ-ZF domains and discovered an unknown Drosophila gene, dPLZF, which encodes an orthologue of human PLZF. We then characterized the biological function of the dPLZF via genetic interaction analysis. Ectopic expression of dPLZF in the wing induced extra vein formation during wing development in Drosophila. Genetic interactions between dPLZF and Ras or extracellular signal-regulated kinase (ERK) significantly enhanced the formation of vein cells. On the other hand, loss-of-function mutations in dPLZF resulted in a dramatic suppression of the extra and ectopic vein formation induced by elevated Ras/ERK signaling. Moreover, dPLZF activity upregulated the expression of rhomboid (rho) and spitz, which perform crucial functions in vein cell formation in the developing wing. These results indicate that dPLZF is a transcription factor controlled by the Ras/ERK signaling pathway, which is a prominent regulator of vein cell formation during wing development in Drosophila.

Keywords: BTB/POZ, ERK, PLZF, Ras, zinc finger