title: Requirement of Wnt/beta-catenin signaling in pronephric kidney development.
abstract: The pronephric kidney controls water and electrolyte balance during early fish and amphibian embryogenesis. Many Wnt signaling components have been implicated in kidney development. Specifically, in Xenopus pronephric development as well as the murine metanephroi, the secreted glycoprotein Wnt-4 has been shown to be essential for renal tubule formation. Despite the importance of Wnt signals in kidney organogenesis, little is known of the definitive downstream signaling pathway(s) that mediate their effects. Here we report that inhibition of Wnt/beta-catenin signaling within the pronephric field of Xenopus results in significant losses to kidney epithelial tubulogenesis with little or no effect on adjoining axis or somite development. We find that the requirement for Wnt/beta-catenin signaling extends throughout the pronephric primordium and is essential for the development of proximal and distal tubules of the pronephros as well as for the development of the duct and glomus. Although less pronounced than effects upon later pronephric tubule differentiation, inhibition of the Wnt/beta-catenin pathway decreased expression of early pronephric mesenchymal markers indicating it is also needed in early pronephric patterning. We find that upstream inhibition of Wnt/beta-catenin signals in zebrafish likewise reduces pronephric epithelial tubulogenesis. We also find that exogenous activation of Wnt/beta-catenin signaling within the Xenopus pronephric field results in significant tubulogenic losses. Together, we propose Wnt/beta-catenin signaling is required for pronephric tubule, duct and glomus formation in Xenopus laevis, and this requirement is conserved in zebrafish pronephric tubule formation.
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 1000, Houston, TX 77030, USA.
authors.forename: Jon P
authors.initials: JP
authors.lastname: Lyons
authors.forename: Rachel K
authors.initials: RK
authors.lastname: Miller
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Zhou
authors.forename: Gilbert
authors.initials: G
authors.lastname: Weidinger
authors.forename: Tom
authors.initials: T
authors.lastname: Deroo
authors.forename: Tinneke
authors.initials: T
authors.lastname: Denayer
authors.forename: Jae-Il
authors.initials: JI
authors.lastname: Park
authors.forename: Hong
authors.initials: H
authors.lastname: Ji
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Hong
authors.forename: Annette
authors.initials: A
authors.lastname: Li
authors.forename: Randall T
authors.initials: RT
authors.lastname: Moon
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Jones
authors.forename: Kris
authors.initials: K
authors.lastname: Vleminckx
authors.forename: Peter D
authors.initials: PD
authors.lastname: Vize
authors.forename: Pierre D
authors.initials: PD
authors.lastname: McCrea
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D007668:Kidney / Q000196:embryology* / Q000378:metabolism*; D007685:Kidney Tubules, Collecting / Q000196:embryology / Q000378:metabolism; D007814:Larva / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D038081:Organogenesis; D010641:Phenotype; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D019170:Somites / Q000196:embryology; D051153:Wnt Proteins / Q000378:metabolism*; D014981:Xenopus / Q000196:embryology* / Q000235:genetics; D029867:Xenopus Proteins / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D015415:Biomarkers; C081542:En1 protein, Xenopus; D018398:Homeodomain Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D051153:Wnt Proteins; D029867:Xenopus Proteins; D051176:beta Catenin; C110182:dkk1 protein, Xenopus; C113267:nephrin