B. Kerber et al., 7-UP, THE DROSOPHILA HOMOLOG OF THE COUP-TF ORPHAN RECEPTORS CONTROLSCELL-PROLIFERATION IN THE INSECT KIDNEY, Genes & development, 12(12), 1998, pp. 1781-1786
Morphogenesis of the insect kidney, the Malpighian tubules, is control
led in Drosophila by a single large cell, the tip cell. It has been po
stulated that this cell sends out a mitogenic signal that induces the
division of neighboring cells. The signal and the molecules that recei
ve it have remained elusive. We show that the COUP-TF-related nuclear
orphan receptor Seven-up is a key component that becomes induced in re
sponse to mitogenic EGF receptor signaling activity emanating from the
tip cell. Seven-up in turn is capable of regulating the transcription
of cell cycle regulators.