title: Identification and comparative expression analysis of a second wt1 gene in zebrafish.
abstract: The Wilms' tumor suppressor gene wt1 encodes a zinc-finger transcription factor that plays an important role in the development of the mammalian genitourinary system. Mutations in WT1 in humans lead to anomalies of kidney and gonad development and cause Wilms' tumor, a pediatric kidney cancer. The inactivation of both wt1 alleles in mice gives rise to multiple organ defects, among them agenesis of kidney, spleen, and gonads. In zebrafish, an ortholog of wt1 has been described that is expressed in the pronephric field and is later restricted to the podocytes. Here, we report the existence of a second wt1 gene in zebrafish, which we have named wt1b (we named the initial gene wt1a). The overall sequence identity of the two Wt1 proteins is 70% and 92% between the zinc-finger regions, respectively. In contrast to wt1a, wt1b is expressed from the earliest stages of development onward, albeit at low levels. Both wt1a and wt1b are expressed in the intermediate mesoderm, with wt1b being restricted to a smaller area lying at the caudal end of the wt1a expression domain. In adult fish, high expression levels for both genes can be found in gonads, kidney, heart, spleen, and muscle.
authors.affiliation: Leibniz Institute for Age Research-Fritz Lipmann Institute e.V. (FLI), Jena, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Bollig
authors.forename: Rebecca
authors.initials: R
authors.lastname: Mehringer
authors.forename: Birgit
authors.initials: B
authors.lastname: Perner
authors.forename: Christina
authors.initials: C
authors.lastname: Hartung
authors.forename: Matthias
authors.initials: M
authors.lastname: Schäfer
authors.forename: Manfred
authors.initials: M
authors.lastname: Schartl
authors.forename: Jean-Nicolas
authors.initials: JN
authors.lastname: Volff
authors.forename: Christoph
authors.initials: C
authors.lastname: Winkler
authors.forename: Christoph
authors.initials: C
authors.lastname: Englert
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004625:Embryo, Nonmammalian / Q000737:chemistry / Q000196:embryology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D025721:WT1 Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology / Q000235:genetics* / Q000254:growth & development
chemical_list: D025721:WT1 Proteins