title: Tre1, a G protein-coupled receptor, directs transepithelial migration of Drosophila germ cells.
abstract: In most organisms, germ cells are formed distant from the somatic part of the gonad and thus have to migrate along and through a variety of tissues to reach the gonad. Transepithelial migration through the posterior midgut (PMG) is the first active step during Drosophila germ cell migration. Here we report the identification of a novel G protein-coupled receptor (GPCR), Tre1, that is essential for this migration step. Maternal tre1 RNA is localized to germ cells, and tre1 is required cell autonomously in germ cells. In tre1 mutant embryos, most germ cells do not exit the PMG. The few germ cells that do leave the midgut early migrate normally to the gonad, suggesting that this gene is specifically required for transepithelial migration and that mutant germ cells are still able to recognize other guidance cues. Additionally, inhibiting small Rho GTPases in germ cells affects transepithelial migration, suggesting that Tre1 signals through Rho1. We propose that Tre1 acts in a manner similar to chemokine receptors required during transepithelial migration of leukocytes, implying an evolutionarily conserved mechanism of transepithelial migration. Recently, the chemokine receptor CXCR4 was shown to direct migration in vertebrate germ cells. Thus, germ cells may more generally use GPCR signaling to navigate the embryo toward their target.
authors.affiliation: Howard Hughes Medical Institute, Developmental Genetics Program, New York University School of Medicine, New York, New York, USA.
authors.forename: Prabhat S
authors.initials: PS
authors.lastname: Kunwar
authors.forename: Michelle
authors.initials: M
authors.lastname: Starz-Gaiano
authors.forename: Roland J
authors.initials: RJ
authors.lastname: Bainton
authors.forename: Ulrike
authors.initials: U
authors.lastname: Heberlein
authors.forename: Ruth
authors.initials: R
authors.lastname: Lehmann
mesh_terms: D000818:Animals; D002465:Cell Movement; D017690:Cell Transplantation; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster; D004625:Embryo, Nonmammalian / Q000378:metabolism; D004848:Epithelium / Q000473:pathology*; D019143:Evolution, Molecular; D005260:Female; D005786:Gene Expression Regulation; D005854:Germ Cells / Q000166:cytology*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007249:Inflammation; D007962:Leukocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D010802:Phylogeny; D012313:RNA / Q000737:chemistry / Q000378:metabolism; D019707:Receptors, Chemokine / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D019707:Receptors, Chemokine; D043562:Receptors, G-Protein-Coupled; C410682:Tre1 protein, Drosophila; D012313:RNA; C511153:Rho1 protein, Drosophila; D020741:rho GTP-Binding Proteins