title: Transcription factor zfh1 downregulates Drosophila Imd pathway.
abstract: The fruit fly Drosophila melanogaster has a powerful innate immune system, which culminates on the synthesis of potent antimicrobial peptides (AMPs). This is mainly controlled by two conserved signaling cascades, the Toll and the immune deficiency (Imd) pathways. Like in humans, Drosophila immune responses need to be under tight control at multiple levels to avoid harmful inflammation. We have identified the transcription factor Zn finger homeodomain 1 (zfh1) as a negative regulator of Drosophila Imd signaling. Knocking down zfh1 in Drosophila S2 cells hyperactivates Imd pathway-mediated AMP expression, whereas forced zfh1 expression blocks Imd pathway response downstream of, or parallel to, the Imd pathway transcription factor Relish. In vivo zfh1 RNAi hyperactivates CecropinB induction upon gram-negative bacterial infection. We conclude that zfh1 is an important regulator of the immune response in Drosophila.
authors.affiliation: Institute of Biomedical Technology and BioMediTech, University of Tampere, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Myllymäki
authors.forename: M
authors.initials: M
authors.lastname: Rämet
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000378:metabolism; D002460:Cell Line; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000276:immunology* / Q000382:microbiology; D005786:Gene Expression Regulation; D007113:Immunity, Innate / Q000235:genetics; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000276:immunology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation / Q000235:genetics; D019076:Transgenes / Q000235:genetics
chemical_list: D023181:Antimicrobial Cationic Peptides; D029721:Drosophila Proteins; D019476:Insect Proteins; D034741:RNA, Small Interfering; C101626:Rel protein, Drosophila; D012097:Repressor Proteins; D014157:Transcription Factors; C115150:cecropin B1 protein, insect; C439909:imd protein, Drosophila; C081010:zfh1 protein, Drosophila