The decapentaplegic (dpp) gene of Drosophila melanogaster Is required for pattern formation in the embryo and for viability of the epithelial cells in the imaginal disks. The dpp protein product predicted from the DNA sequence is similar to members of a family of growth factors that includes transforming growth factor 0 (TGF-1). We have produced polyclonal antibodies to a recombinant dpp protein made in bacteria and used a metallothionein promoter to express a dpp cDNA in Drosophila S2 cells. Similar to other proteins in the TGF-4 family, the dpp protein produced by the Drosophila cells was proteolytically cleaved, and both portions of the protein were secreted from the cells. The amino-terminal 47-kilodalton (kDa) peptide was found in the medium and in the proteins adhering to the plastic petri dish. The carboxy-terminal peptide, the region with sequence similarity to the active ligand portion of TGF-4, was found extracellularly as a 30-kDa homodimer. Most of the 30-kDa homodimer was in the S2 cell protein adsorbed onto the surface of the plastic dish. The dpp protein could be released into solution by increased salt concentration and nonionic detergent. Under these conditions, the amino-terminal and carboxy-terminal portions of dpp were not associated in a stable complex.Analysis of mutant alleles in the Drosophila decapentaplegic (dpp) gene indicates that the dpp gene product is required for the proper development of the embryonic dorsal hypoderm (18), for viability of larvae (42), and for cell viability of the epithelial cells in the imaginal disks (5, 45). Molecular isolation of the dpp DNA and mapping of mutant lesions onto the molecular map indicates that the gene spans over 50 kilobases (kb) of DNA (R. D. St. Johnston, F. M. Hoffmann, R. K. Blackman, D. Segal, R. Grimaila, R. W. Padgett, H. A. Irick, and W. M. Gelbart, Genes Dev., in press). The two protein-coding exons are located near the center of this region, and their expression is driven from at least five promoters distributed across 20 kb of 5' DNA. dpp expression in the larval imaginal disks requires cis-regulatory elements distributed across 25 kb of DNA 3' to the coding exons.The two exons that are common to all of the transcriptional units contain an open reading frame whose predicted protein product is 588 amino acids in length; the carboxyterminal 100 amino acids have sequence similarity to proteins in the transforming growth factor P (TGF-P) superfamily, which at this time includes five TGF-1s, Mullerian inhibiting substance (MIS), inhibins, the Xenopus protein Vg-1, the mouse protein Vgr-1, and three human bone morphogens (BMPs) (7,10,24,25,35,47,50,52). Sequence similarities to this 100-amino-acid region are highest between dpp and human bone morphogenetic proteins (75%) or murine Vgr-1 protein (77%) and range between 23 and 57% for the other members of the TGF-1 family (25,52); the conserved amino acids include all seven cysteine residues in dpp. All of the vertebrate proteins examined to date are secreted proteins in which the carboxy-...
The decapentaplegic (dpp) gene of Drosophila melanogaster is required for pattern formation in the embryo and for viability of the epithelial cells in the imaginal disks. The dpp protein product predicted from the DNA sequence is similar to members of a family of growth factors that includes transforming growth factor beta (TGF-beta). We have produced polyclonal antibodies to a recombinant dpp protein made in bacteria and used a metallothionein promoter to express a dpp cDNA in Drosophila S2 cells. Similar to other proteins in the TGF-beta family, the dpp protein produced by the Drosophila cells was proteolytically cleaved, and both portions of the protein were secreted from the cells. The amino-terminal 47-kilodalton (kDa) peptide was found in the medium and in the proteins adhering to the plastic petri dish. The carboxy-terminal peptide, the region with sequence similarity to the active ligand portion of TGF-beta, was found extracellularly as a 30-kDa homodimer. Most of the 30-kDa homodimer was in the S2 cell protein adsorbed onto the surface of the plastic dish. The dpp protein could be released into solution by increased salt concentration and nonionic detergent. Under these conditions, the amino-terminal and carboxy-terminal portions of dpp were not associated in a stable complex.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.