Drosophila Myc is required for normal DREF gene expression.
The Drosophila DNA replication-related element-binding factor (dDREF) is required for the expression of many proliferation-related genes carrying the DRE sequence, 5'-TATCGATA. Finding a canonical E-box, 5'-CACGTG, in the dDREF gene promoter prompted us to explore the possibility that the dDREF gene is a target of Drosophila Myc (dMyc). Luciferase transient expression assays combined with RNA interference in Drosophila S2 cells revealed that knockdown of dmyc reduced dDREF gene promoter activity by 35% to 82%, an effect at least partly mediated by the E-box in the promoter. dm(4)/Y hemizygous mutant larvae demonstrated no maternal dMyc and severe impairment of dDREF mRNA transcription. dMyc loss of function in dm(2)/dm(2) homozygous mutant follicle cell clones also resulted in loss of anti-dDREF immunostaining in nuclei. In contrast, co-expression of dMyc-dMax up-regulated dDREF promoter activity in S2 cells. Furthermore, dMyc over-expressing clones exhibited a high level of dDREF gene expression in wing and eye discs. These results taken together indicate that dMyc is indeed required for dDREF gene expression.
Thao
Dang Thi Phuong
DT
Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
Seto
Hirokazu
H
Yamaguchi
Masamitsu
M
D000818:Animals; D002460:Cell Line; D002999:Clone Cells / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism*; D024721:E-Box Elements / Q000235:genetics*; D005123:Eye / Q000254:growth & development; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008297:Male; D011401:Promoter Regions, Genetic / Q000235:genetics*; D034622:RNA Interference / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics; D014921:Wings, Animal / Q000254:growth & development
D004268:DNA-Binding Proteins; C099494:Dref protein, Drosophila; D029721:Drosophila Proteins; C102284:Myc protein, Drosophila; D012333:RNA, Messenger; D014157:Transcription Factors