Localized Notch signal acts through eyg and upd to promote global growth in Drosophila eye.
Notch (N) signal is activated at the dorsoventral (DV) border of the Drosophila eye disc and is important for growth of the eye disc. In this study, we showed that the Pax protein Eyg is a major effector mediating the growth promotion function of N. eyg transcription is induced by N signaling occurring at the DV border. Like N, eyg controls growth of the eye disc. Loss of N signaling can be compensated by overexpressing eyg, whereas loss of the downstream eyg blocked the function of N signaling. In addition, we showed that N and eyg could induce expression of upd, which encodes the ligand for the Jak/STAT pathway and acts over long distance to promote cell proliferation. Loss of eyg or N can be compensated by overexpressing upd. These results suggest that upd is a major effector mediating the function of eyg and N. The functional link from N to eyg to upd explains how the localized Notch activation can achieve global growth control.
Chao
Ju-Lan
JL
Institute of Genetics, National Yang-Ming University, Taipei 111, Taiwan, Republic of China.
Tsai
Yu-Chen
YC
Chiu
Sue-Jean
SJ
Sun
Y Henry
YH
D000818:Animals; D002455:Cell Division / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004330:Drosophila / Q000254:growth & development*; D029721:Drosophila Proteins / Q000378:metabolism*; D005123:Eye / Q000254:growth & development*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D008565:Membrane Proteins / Q000378:metabolism*; D051880:Receptors, Notch; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism*
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D008565:Membrane Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch; D014157:Transcription Factors; C477040:eyg protein, Drosophila; C115570:upd1 protein, Drosophila