Transcriptional Regulation of the Drosophila rafProto-oncogene by Drosophila STAT during Development and in Immune Response

• Published in: The Journal of biological chemistry Vol. 275; no. 26; pp. 19824 - 19830
• Main Authors: Kwon, Eun-Jeong, Park, Hyun-Sook, Kim, Young-Shin, Oh, Eun-Jin, Nishida, Yasuyoshi, Matsukage, Akio, Yoo, Mi-Ae, Yamaguchi, Masamitsu
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 30.06.2000; American Society for Biochemistry and Molecular Biology
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M001114200

The Drosophila raf(D-raf) gene promoter contains a recognition consensus sequence for Drosophila STAT (D-STAT). By band mobility shift assay, we detected a factor binding to the D-STAT-recognition sequence in extracts of cultured Drosophila cells treated with vanadate peroxide. UV-cross-linking analyses suggested the size of the binding factor to be almost same as that of D-STAT. Furthermore, the binding activity was increased in cells cotransfected with HOP and D-STAT expression plasmids. These results strongly suggest that D-STAT binds to the D-STAT recognition sequence in the D-raf gene promoter. Transient luciferase expression assay using Schneider 2 cells indicated that the D-raf gene promoter is activated by D-STAT through the D-STAT-binding site. Furthermore, analyses with transgenic flies carrying Draf-lacZ fusion genes with and without mutations in the D-STAT-binding site pointed to an important role in D-raf gene promoter activity throughout development. We also found that the D-STAT-binding site is required for injury-induced activation of the D-raf gene promoter. Here we propose that D-STAT can participate in regulation of the mitogen-activated protein kinase cascade through D-raf gene activation.