title: Genomic characterization of Wilms' tumor suppressor 1 targets in nephron progenitor cells during kidney development.
abstract: The Wilms' tumor suppressor 1 (WT1) gene encodes a DNA- and RNA-binding protein that plays an essential role in nephron progenitor differentiation during renal development. To identify WT1 target genes that might regulate nephron progenitor differentiation in vivo, we performed chromatin immunoprecipitation (ChIP) coupled to mouse promoter microarray (ChIP-chip) using chromatin prepared from embryonic mouse kidney tissue. We identified 1663 genes bound by WT1, 86% of which contain a previously identified, conserved, high-affinity WT1 binding site. To investigate functional interactions between WT1 and candidate target genes in nephron progenitors, we used a novel, modified WT1 morpholino loss-of-function model in embryonic mouse kidney explants to knock down WT1 expression in nephron progenitors ex vivo. Low doses of WT1 morpholino resulted in reduced WT1 target gene expression specifically in nephron progenitors, whereas high doses of WT1 morpholino arrested kidney explant development and were associated with increased nephron progenitor cell apoptosis, reminiscent of the phenotype observed in Wt1(-/-) embryos. Collectively, our results provide a comprehensive description of endogenous WT1 target genes in nephron progenitor cells in vivo, as well as insights into the transcriptional signaling networks controlled by WT1 that might direct nephron progenitor fate during renal development.
authors.affiliation: Department of Medicine, Children's Hospital Boston; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Sunny
authors.initials: S
authors.lastname: Hartwig
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Ho
authors.forename: Priyanka
authors.initials: P
authors.lastname: Pandey
authors.forename: Kenzie
authors.initials: K
authors.lastname: Macisaac
authors.forename: Mary
authors.initials: M
authors.lastname: Taglienti
authors.forename: Michael
authors.initials: M
authors.lastname: Xiang
authors.forename: Gil
authors.initials: G
authors.lastname: Alterovitz
authors.forename: Marco
authors.initials: M
authors.lastname: Ramoni
authors.forename: Ernest
authors.initials: E
authors.lastname: Fraenkel
authors.forename: Jordan A
authors.initials: JA
authors.lastname: Kreidberg
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001483:Base Sequence; D047369:Chromatin Immunoprecipitation; D016208:Databases, Factual; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D007668:Kidney / Q000166:cytology* / Q000196:embryology* / Q000378:metabolism; D051379:Mice; D046228:Microarray Analysis; D009399:Nephrons / Q000166:cytology* / Q000196:embryology / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000378:metabolism; D011247:Pregnancy; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*; D046509:Tissue Culture Techniques; D025721:WT1 Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D016376:Oligonucleotides, Antisense; D025721:WT1 Proteins