DREF is required for EGFR signalling during Drosophila wing vein development.
The DNA replication-related element binding factor (DREF) has been suggested as being involved in regulation of DNA replication- and proliferation-related genes in Drosophila. Recently, by searching the Drosophila genome database, we also found DRE-like sequences in the 5'-flanking regions of many genes with other functions. In addition, immunostaining of polytene chromosomes with an anti-DREF monoclonal antibody revealed that DREF can bind to a hundred regions of polytene chromosomes, suggesting regulation of multiple genes and multiple roles in vivo. When we over-expressed DREF protein or inverted repeat RNA of the DREF gene in wing imaginal discs using the GAL4-UAS targeted expression system in Drosophila, the results were veins of increased width and a loss of veins, respectively. With DREF over-expression, Rolled, a Drosophila MAPK homologue, was ectopically activated. Furthermore, half reduction of the D-raf gene dose suppressed this DREF-induced vein of increased width phenotype. In addition, when DREF transcripts were reduced by introducing double-stranded RNA of the DREF gene into S2 cells, the D-raf gene promoter activity was diminished to 4%. These data indicate that DREF is involved in regulation of vein formation through the activation of EGFR signalling in the Drosophila wing imaginal discs.
Yoshida
Hideki
H
Venture Laboratory, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan.
Kwon
Eunjeong
E
Hirose
Fumiko
F
Otsuki
Kyoko
K
Yamada
Mikihiro
M
Yamaguchi
Masamitsu
M
D000818:Animals; D004330:Drosophila / Q000254:growth & development* / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism*; D004789:Enzyme Activation / Q000502:physiology; D066246:ErbB Receptors / Q000378:metabolism*; D005124:Eye Abnormalities / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D019908:Proto-Oncogene Proteins c-raf / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism*; D014921:Wings, Animal / Q000254:growth & development* / Q000378:metabolism
C099494:Dref protein, Drosophila; D029721:Drosophila Proteins; D014157:Transcription Factors; D066246:ErbB Receptors; D019908:Proto-Oncogene Proteins c-raf; C420924:Raf protein, Drosophila; D020928:Mitogen-Activated Protein Kinases