Different contributions of pannier and wingless to the patterning of the dorsal mesothorax of Drosophila

• Published in: Development (Cambridge) Vol. 126; no. 16; pp. 3523 - 3532
• Main Authors: García-García, M J, Ramain, P, Simpson, P, Modolell, J
• Format: Journal Article
• Language: English
• Published: England The Company of Biologists Limited 01.08.1999; Company of Biologists
• Subjects: achaete gene; achaete-scute gene; Animals; Animals, Genetically Modified; Base Sequence; Basic Helix-Loop-Helix Transcription Factors; Body Patterning - physiology; Development Biology; DNA-Binding Proteins - genetics; Drosophila; Drosophila - embryology; Drosophila - genetics; Drosophila Proteins; Enhancer Elements, Genetic; GATA protein; Gene Expression Regulation, Developmental; Insect Proteins - genetics; Life Sciences; mesothorax; Molecular Sequence Data; Mosaicism; Mutagenesis, Site-Directed; Nervous System - embryology; pannier gene; Pannier protein; Proto-Oncogene Proteins - metabolism; Recombinant Proteins - biosynthesis; Repressor Proteins - genetics; Repressor Proteins - metabolism; scute gene; Thorax; Transcription Factors - genetics; Transcription Factors - metabolism; wingless gene; Wingless protein; Wnt1 Protein; Zinc Fingers
• ISSN: 0950-1991; 1477-9129
• DOI: 10.1242/dev.126.16.3523

In Drosophila, the GATA family transcription factor Pannier and the Wnt secreted protein Wingless are known to be important for the patterning of the notum, a part of the dorsal mesothorax of the fly. Thus, both proteins are necessary for the development of the dorsocentral mechanosensory bristles, although their roles in this process have not been clarified. Here, we show that Pannier directly activates the proneural genes achaete and scute by binding to the enhancer responsible for the expression of these genes in the dorsocentral proneural cluster. Moreover, the boundary of the expression domain of Pannier appears to delimit the proneural cluster laterally, while antagonism of Pannier function by the Zn-finger protein U-shaped sets its limit dorsally. So, Pannier and U-shaped provide positional information for the patterning of the dorsocentral cluster. In contrast and contrary to previous suggestions, Wingless does not play a similar role, since the levels and vectorial orientation of its concentration gradient in the dorsocentral area can be greatly modified without affecting the position of the dorsocentral cluster. Thus, Wingless has only a permissive role on dorsocentral achaete-scute expression. We also provide evidence indicating that Pannier and U-shaped are main effectors of the regulation of wingless expression in the presumptive notum.