title: Functions for Drosophila brachyenteron and forkhead in mesoderm specification and cell signalling.
abstract: The visceral musculature of the larval midgut of Drosophila has a lattice-type structure and consists of an inner stratum of circular fibers and an outer stratum of longitudinal fibers. The longitudinal fibers originate from the posterior tip of the mesoderm anlage, which has been termed the caudal visceral mesoderm (CVM). In this study, we investigate the specification of the CVM and particularly the role of the Drosophila Brachyury-homologue brachyenteron. Supported by fork head, brachyenteron mediates the early specification of the CVM along with zinc-finger homeodomain protein-1. This is the first function described for brachyenteron or fork head in the mesoderm of Drosophila. The mode of cooperation resembles the interaction of the Xenopus homologues Xbra and Pintallavis. Another function of brachyenteron is to establish the surface properties of the CVM cells, which are essential for their orderly migration along the trunk-derived visceral mesoderm. During this movement, the CVM cells, under the control of brachyenteron, induce the formation of one muscle/pericardial precursor cell in each parasegment. We propose that the functions of brachyenteron in mesodermal development of Drosophila are comparable to the roles of the vertebrate Brachyury genes during gastrulation.
authors.affiliation: Institut für Genetik, Universität zu Köln, Weyertal 121, D-50931 Köln, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Kusch
authors.forename: R
authors.initials: R
authors.lastname: Reuter
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004064:Digestive System / Q000196:embryology; D004330:Drosophila / Q000196:embryology* / Q000235:genetics / Q000254:growth & development; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian; D004627:Embryonic Induction / Q000235:genetics; D051858:Forkhead Transcription Factors; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism*; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins; D015398:Signal Transduction; D013499:Surface Properties; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D051879:Twist-Related Protein 1; D014781:Viscera / Q000196:embryology; D016335:Zinc Fingers / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D051858:Forkhead Transcription Factors; D019476:Insect Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D051879:Twist-Related Protein 1; C081010:zfh1 protein, Drosophila