Mirror represses pipe expression in follicle cells to initiate dorsoventral axis formation in Drosophila

• Published in: Development (Cambridge) Vol. 139; no. 6; pp. 1110 - 1114
• Main Authors: Andreu, María José, González-Pérez, Esther, Ajuria, Leiore, Samper, Núria, González-Crespo, Sergio, Campuzano, Sonsoles, Jiménez, Gerardo
• Format: Journal Article
• Language: English
• Published: England 15.03.2012
• Subjects: Animals; Body Patterning - genetics; Conserved Sequence; Drosophila; Drosophila melanogaster - cytology; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Drosophila melanogaster - metabolism; Drosophila Proteins - biosynthesis; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Embryo, Nonmammalian - metabolism; ErbB Receptors - metabolism; Eye Proteins - metabolism; Female; Gene Expression Regulation, Developmental; HMGB Proteins - metabolism; Homeodomain Proteins - metabolism; Ovarian Follicle - cytology; Ovarian Follicle - embryology; Ovarian Follicle - metabolism; Receptors, Invertebrate Peptide - metabolism; Regulatory Sequences, Nucleic Acid; Repressor Proteins - metabolism; Signal Transduction; Sulfotransferases - biosynthesis; Sulfotransferases - genetics; Sulfotransferases - metabolism; Transcription Factors - metabolism
• ISSN: 0950-1991; 1477-9129
• DOI: 10.1242/dev.076562

Dorsoventral (DV) axis formation in Drosophila begins with selective activation of EGFR, a receptor tyrosine kinase (RTK), in dorsal-anterior (DA) ovarian follicle cells. A critical event regulated by EGFR signaling is the repression of the sulfotransferase-encoding gene pipe in dorsal follicle cells, but how this occurs remains unclear. Here we show that Mirror (Mirr), a homeodomain transcription factor induced by EGFR signaling in DA follicle cells, directly represses pipe expression by binding to a conserved element in the pipe regulatory region. In addition, we find that the HMG-box protein Capicua (Cic) supports pipe expression in ventral follicle cells by repressing Mirr in this region. Interestingly, this role of Cic resembles its function in regulating anteroposterior (AP) body patterning, where Cic supports gap gene expression in central regions of the embryo by repressing Tailless, a repressor induced by RTK signaling at the embryonic poles. Thus, related RTK-Cic repressor circuits regulate the early stages of Drosophila DV and AP body axis formation.