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Smith C, Burugula BB, Dunn I, Aradhya S, Kitzman JO, Yee JL. High-Throughput Splicing Assays Identify Known and Novel WT1 Exon 9 Variants in Nephrotic Syndrome. Kidney Int Rep 2023; 8:2117-2125. [PMID: 37850022 PMCID: PMC10577367 DOI: 10.1016/j.ekir.2023.07.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 07/31/2023] [Indexed: 10/19/2023] Open
Abstract
Introduction Frasier syndrome (FS) is a rare Mendelian form of nephrotic syndrome (NS) caused by variants which disrupt the proper splicing of WT1. This key transcription factor gene is alternatively spliced at exon 9 to produce 2 isoforms ("KTS+" and "KTS-"), which are normally expressed in the kidney at a ∼2:1 (KTS+:KTS-) ratio. FS results from variants that reduce this ratio by disrupting the splice donor of the KTS+ isoform. FS is extremely rare, and it is unclear whether any variants beyond the 8 already known could cause FS. Methods To prospectively identify other splicing-disruptive variants, we leveraged a massively parallel splicing assay. We tested every possible single nucleotide variant (n = 519) in and around WT1 exon 9 for effects upon exon inclusion and KTS+/- ratio. Results Splice disruptive variants (SDVs) made up 11% of the tested point variants overall and were tightly concentrated near the canonical acceptor and the KTS+/- alternate donors. Our map successfully identified all 8 known FS or focal segmental glomerulosclerosis (FSGS) variants and 16 additional novel variants which were comparably disruptive to these known pathogenic variants. We also identified 19 variants that, conversely, increased the KTS+/KTS- ratio, of which 2 are observed in unrelated individuals with 46,XX ovotesticular disorder of sex development (46,XX OTDSD). Conclusion This splicing effect map can serve as functional evidence to guide the clinical interpretation of newly observed variants in and around WT1 exon 9.
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Affiliation(s)
- Cathy Smith
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Bala Bharathi Burugula
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ian Dunn
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | | | - Jacob O. Kitzman
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jennifer Lai Yee
- Department of Pediatrics, Division of Nephrology, University of Michigan, Ann Arbor, Michigan, USA
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Shao Q, Xie X, Geng J, Yang X, Li W, Zhang Y. Frasier Syndrome: A 15-Year-Old Phenotypically Female Adolescent Presenting with Delayed Puberty and Nephropathy. CHILDREN 2023; 10:children10030577. [PMID: 36980135 PMCID: PMC10046944 DOI: 10.3390/children10030577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/14/2023] [Accepted: 03/15/2023] [Indexed: 03/19/2023]
Abstract
Frasier syndrome (FS) is a rare inherited disorder characterized by gonadal dysgenesis and progressive nephropathy, resulting from mutations in the intron 9 splice donor site of the Wilms tumor 1 (WT1) gene. It is associated with male gonadal dysgenesis (female external genitalia with a 46 XY karyotype), and a high risk of gonadoblastoma during adolescence. Patients with FS present early in childhood with proteinuria that progressively worsens with a high likelihood of end-stage renal disease (ESRD). Herein, we report a 15-year-old female (karyotype 46, XY) patient characterized by delayed puberty and steroid-resistant nephrotic syndrome, in whom whole genome sequencing showed a mutation in intron 9 of the WT1 gene, c.1447 + 4 C>T. This is the first case of FS with delayed puberty as the first complaint with no previous renal symptoms. We consider delayed puberty as an important manifestation of FS and summarize the diagnostic process of delayed puberty in the female phenotype. For clinicians, delayed puberty is a common disorder in pediatrics but requires vigilance for some rare causes. Etiological screening and chromosome karyotype analysis are important for the early diagnosis of FS in patients with delayed puberty.
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Affiliation(s)
- Qing Shao
- Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Xinglei Xie
- Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Jia Geng
- Institute of Rare Diseases, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Xiaoling Yang
- Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Wei Li
- Outpatient Department, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yuwei Zhang
- Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, Chengdu 610041, China
- Correspondence:
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3
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Zhang B, Ding Y, Ren X, Song C, Zhang X, Wang F, Yang X. Congenital diaphragmatic eventration with pulmonary dysplasia in frasier due to a WT1 mutation of c.1432+5(IVS9)G>A. Eur J Med Genet 2022; 65:104655. [DOI: 10.1016/j.ejmg.2022.104655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 10/14/2022] [Accepted: 10/20/2022] [Indexed: 11/25/2022]
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Sambharia M, Rastogi P, Thomas CP. Monogenic focal segmental glomerulosclerosis: A conceptual framework for identification and management of a heterogeneous disease. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2022; 190:377-398. [PMID: 35894442 PMCID: PMC9796580 DOI: 10.1002/ajmg.c.31990] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/31/2022] [Accepted: 06/30/2022] [Indexed: 01/29/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is not a disease, rather a pattern of histological injury occurring from a variety of causes. The exact pathogenesis has yet to be fully elucidated but is likely varied based on the type of injury and the primary target of that injury. However, the approach to treatment is often based on the degree of podocyte foot process effacement and clinical presentation without sufficient attention paid to etiology. In this regard, there are many monogenic causes of FSGS with variable presentation from nephrotic syndrome with histological features of primary podocytopathy to more modest degrees of proteinuria with limited evidence of podocyte foot process injury. It is likely that genetic causes are largely underdiagnosed, as the role and the timing of genetic testing in FSGS is not established and genetic counseling, testing options, and interpretation of genotype in the context of phenotype may be outside the scope of practice for both nephrologists and geneticists. Yet most clinicians believe that a genetic diagnosis can lead to targeted therapy, limit the use of high-dose corticosteroids as a therapeutic trial, and allow the prediction of the natural history and risk for recurrence in the transplanted kidney. In this manuscript, we emphasize that genetic FSGS is not monolithic in its presentation, opine on the importance of genetic testing and provide an algorithmic approach to deployment of genetic testing in a timely fashion when faced with a patient with FSGS.
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Affiliation(s)
- Meenakshi Sambharia
- Division of Nephrology, Department of Internal MedicineUniversity of IowaIowa CityIowaUSA
| | - Prerna Rastogi
- Department of PathologyUniversity of IowaIowa CityIowaUSA
| | - Christie P. Thomas
- Division of Nephrology, Department of Internal MedicineUniversity of IowaIowa CityIowaUSA,Department of PediatricsUniversity of IowaIowa CityIowaUSA,The Iowa Institute of Human GeneticsUniversity of IowaIowa CityIowaUSA,Medical ServiceVeterans Affairs Medical CenterIowa CityIowaUSA
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5
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Ferrari MTM, Watanabe A, da Silva TE, Gomes NL, Batista RL, Nishi MY, de Paula LCP, Costa EC, Costa EMF, Cukier P, Onuchic LF, Mendonca BB, Domenice S. WT1 Pathogenic Variants are Associated with a Broad Spectrum of Differences in Sex Development Phenotypes and Heterogeneous Progression of Renal Disease. Sex Dev 2021; 16:46-54. [PMID: 34392242 DOI: 10.1159/000517373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 05/14/2021] [Indexed: 11/19/2022] Open
Abstract
Wilms' tumor suppressor gene 1 (WT1) plays an essential role in urogenital and kidney development. Heterozygous germline pathogenic allelic variants of WT1 have been classically associated with Denys-Drash syndrome (DDS) and Frasier syndrome (FS). Usually, exonic pathogenic missense variants in the zinc finger region are the cause of DDS, whereas pathogenic variants affecting the canonic donor lysine-threonine-serine splice site in intron 9 cause FS. Phenotypic overlap between WT1 disorders has been frequently observed. New WT1 variant-associated phenotypes, such as 46,XX testicular/ovarian-testicular disorders of sex development (DSD) and primary ovarian insufficiency, have been reported. In this report, we describe the phenotypes and genotypes of 7 Brazilian patients with pathogenic WT1 variants. The molecular study involved Sanger sequencing and massively parallel targeted sequencing using a DSD-associated gene panel. Six patients (5 with a 46,XY karyotype and 1 with a 46,XX karyotype) were initially evaluated for atypical genitalia, and a 46,XY patient with normal female genitalia sought medical attention for primary amenorrhea. Germ cell tumors were identified in 2 patients, both with variants affecting alternative splicing of WT1 between exons 9 and 10. Two pathogenic missense WT1 variants were identified in two 46,XY individuals with Wilms' tumors; both patients were <1 year of age at the time of diagnosis. A novel WT1 variant, c.1453_1456 (p.Arg485Glyfs*14), was identified in a 46,XX patient with testicular DSD. Nephrotic proteinuria was diagnosed in all patients, including 3 who underwent renal transplantation after progressing to end-stage kidney disease. The expanding phenotypic spectrum associated with WT1 variants in XY and XX individuals confirms their pivotal role in gonadal and renal development as well as in tumorigenesis, emphasizing the clinical implications of these variants in genetic diagnosis.
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Affiliation(s)
- Maria T M Ferrari
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Andreia Watanabe
- Unidade de Nefrologia Pediátrica do Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Disciplina de Nefrologia, LIM-29 - Laboratório de Nefrologia Celular, Genética e Molecular, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Thatiane E da Silva
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Nathalia L Gomes
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Rafael L Batista
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Mirian Y Nishi
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Leila C P de Paula
- Unidade de Desordens do Desenvolvimento Sexual, UFRGS, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Eduardo C Costa
- Unidade de Desordens do Desenvolvimento Sexual, UFRGS, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Elaine M F Costa
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Priscilla Cukier
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Luiz F Onuchic
- Unidade de Nefrologia Pediátrica do Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Disciplina de Nefrologia, LIM-29 - Laboratório de Nefrologia Celular, Genética e Molecular, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Berenice B Mendonca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Sequenciamento em Larga Escala (SELA), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Sorahia Domenice
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Huang YC, Tsai MC, Tsai CR, Fu LS. Frasier Syndrome: A Rare Cause of Refractory Steroid-Resistant Nephrotic Syndrome. CHILDREN-BASEL 2021; 8:children8080617. [PMID: 34438508 PMCID: PMC8394468 DOI: 10.3390/children8080617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/15/2021] [Accepted: 07/20/2021] [Indexed: 11/20/2022]
Abstract
Frasier syndrome is a rare disease that affects the kidneys and genitalia. Patients who have Frasier syndrome develop nephrotic syndrome (NS) featuring focal segmental glomerulosclerosis (FSGS) that is resistant to steroid treatment in early childhood. Male patients can have female external genitalia (pseudo-hermaphroditism) at birth and develop gonado-blastoma in their adolescence. Frasier syndrome is caused by mutations in the splice donor site at intron 9 of the Wilms’ tumor WT1 gene; these mutations result in an imbalanced ratio of WT1 protein isoforms and affect the development of the urogenital tract, podocyte function, and tumor suppression. Here, we report on a patient with long-term refractory NS who developed a malignant mixed germ cell tumor arising in a gonado-blastoma of the ovary 8 years after the onset of proteinuria.
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Affiliation(s)
- Yung-Chieh Huang
- Department of Pediatrics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung 40705, Taiwan; (Y.-C.H.); (M.-C.T.); (C.-R.T.)
| | - Ming-Chin Tsai
- Department of Pediatrics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung 40705, Taiwan; (Y.-C.H.); (M.-C.T.); (C.-R.T.)
| | - Chi-Ren Tsai
- Department of Pediatrics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung 40705, Taiwan; (Y.-C.H.); (M.-C.T.); (C.-R.T.)
- Institute of Molecular Biology, National Chung Hsing University, Taichung 40227, Taiwan
| | - Lin-Shien Fu
- Department of Pediatrics, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Sect. 4, Taichung 40705, Taiwan; (Y.-C.H.); (M.-C.T.); (C.-R.T.)
- Institute of Molecular Biology, National Chung Hsing University, Taichung 40227, Taiwan
- Department of Pediatrics, National Yang-Ming University, Taipei 11221, Taiwan
- Correspondence: ; Tel.: +886-4-23592525 (ext. 5909); Fax: +886-4-23741359
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7
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Nishikawa T, Wojciak JM, Dyson HJ, Wright PE. RNA Binding by the KTS Splice Variants of Wilms' Tumor Suppressor Protein WT1. Biochemistry 2020; 59:3889-3901. [PMID: 32955251 DOI: 10.1021/acs.biochem.0c00602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Wilms' tumor suppressor protein WT1 regulates the expression of multiple genes through binding of the Cys2-His2 zinc finger domain to promoter sites. WT1 has also been proposed to be involved in post-transcriptional regulation, by binding to RNA using the same set of zinc fingers. WT1 has two major splice variants, where the Lys-Thr-Ser (KTS) tripeptide is inserted into the linker between the third and fourth zinc fingers. To obtain insights into the mechanism by which the different WT1 splice variants recognize both DNA and RNA, we have determined the solution structure of the WT1 (-KTS) zinc finger domain in complex with a 29mer stem-loop RNA. Zinc fingers 1-3 bind in a widened major groove favored by the presence of a bulge nucleotide in the double-stranded helical stem. Fingers 2 and 3 make specific contacts with the nucleobases in a conserved AUGG sequence in the helical stem. Nuclear magnetic resonance chemical shift mapping and relaxation analysis show that fingers 1-3 of the two splice variants (-KTS and +KTS) of WT1 form similar complexes with RNA. Finger 4 of the -KTS isoform interacts weakly with the RNA loop, an interaction that is abrogated in the +KTS isoform, and both isoforms bind with similar affinity to the RNA. In contrast, finger 4 is required for high-affinity binding to DNA and insertion of KTS into the linker of fingers 3 and 4 abrogates DNA binding. While finger 1 is required for RNA binding, it is dispensable for binding to consensus DNA sites.
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Affiliation(s)
- Tadateru Nishikawa
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Jonathan M Wojciak
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - H Jane Dyson
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Peter E Wright
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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8
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Transcription factor 21 expression in injured podocytes of glomerular diseases. Sci Rep 2020; 10:11516. [PMID: 32661376 PMCID: PMC7359327 DOI: 10.1038/s41598-020-68422-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 06/24/2020] [Indexed: 11/08/2022] Open
Abstract
Transcription factor 21 (TCF21) is one of the essential transcription factors in kidney development. To elucidate its influence on glomerular disease, we have investigated TCF21 expression in human and rat kidney tissue, and its urinary concentration. Immunohistological analysis suggested the highest TCF21 expression in nephrotic syndrome along with the urinary protein level. Urinary TCF21 concentration in human showed a positive correlation with its podocyte expression level. In nephrotic rat models, TCF21 expression in podocytes increased along with the severity of nephrotic syndrome. Next, in vitro experiments using Tcf21-expressing murine podocyte cell line, we could observe some Tcf21-dependent effects, related with actin cytoskeleton dysregulation and apoptosis. Our study illustrated TCF21 expression changes in vivo and its in vitro-functional significance injured podocytes.
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9
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Expression of Wilm’s Tumor Gene (WT1) in Endometrium with Potential Link to Gestational Vascular Transformation. REPRODUCTIVE MEDICINE 2020. [DOI: 10.3390/reprodmed1010003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Background: Wilm’s tumor 1 gene (WT1) is a transcription factor with versatile cellular functions in embryonic development, the maintenance of adult tissue functions, and regeneration. WT1 is known to be regulated by progesterone and it is abundantly expressed in endometrium, but its function is unclear. Design: in this observational and descriptive study, WT1 expression was detected by immunohistochemical staining in endometrium of various physiological and pathological conditions. Result: WT1 was detected in endometrial stromal cells and vascular smooth muscle cells, in both proliferative and secretory phases of menstrual cycles. WT1 appeared increased in vascular smooth muscle cells in spiral artery in early pregnancy and it was also detected in regenerative endothelial cells and smooth muscle cells in decidual vasculopathy at term. WT1 expression appeared decreased in endometrial stromal cells in adenomyosis (endometriosis). Conclusion: WT1 potentially links the hormonal effects on endometrial decidualization and may play a role in gestational vascular transformation during pregnancy and restoration after pregnancy.
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10
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Duplication of The SOX3 Gene in an Sry-negative 46,XX Male with Associated Congenital Anomalies of Kidneys and the Urinary Tract: Case Report and Review of the Literature. Balkan J Med Genet 2019; 22:81-88. [PMID: 31523625 PMCID: PMC6714342 DOI: 10.2478/bjmg-2019-0006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Disorders of sex development (DSD) are a group of rare conditions characterized by discrepancy between chromosomal sex, gonads and external genitalia. Congenital abnormalities of the kidney and urinary tract are often associated with DSD, mostly in multiple malformation syndromes. We describe the case of an 11-year-old Caucasian boy, with right kidney hypoplasia and hypospadias. Genome-wide copy number variation (CNV) analysis revealed a unique duplication of about 550 kb on chromosome Xq27, and a 46,XX karyotype, consistent with a sex reversal phenotype. This region includes multiple genes, and, among these, SOX3 emerged as the main phenotypic driver. This is the fifth case reporting a genomic imbalance involving the SOX3 gene in a 46,XX SRY-negative male, and the first with associated renal malformations. Our data provide plausible links between SOX3 gene dosage and kidney malformations. It is noteworthy that the current and reported SOX3 gene duplications are below the detection threshold of standard karyotypes and were found only by analyzing CNVs using DNA microarrays. Therefore, all 46,XX SRY-negative males should be screened for SOX3 gene duplications with DNA microarrays.
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11
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Cariati F, D'Argenio V, Tomaiuolo R. The evolving role of genetic tests in reproductive medicine. J Transl Med 2019; 17:267. [PMID: 31412890 PMCID: PMC6694655 DOI: 10.1186/s12967-019-2019-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/06/2019] [Indexed: 02/08/2023] Open
Abstract
Infertility is considered a major public health issue, and approximately 1 out of 6 people worldwide suffer from infertility during their reproductive lifespans. Thanks to technological advances, genetic tests are becoming increasingly relevant in reproductive medicine. More genetic tests are required to identify the cause of male and/or female infertility, identify carriers of inherited diseases and plan antenatal testing. Furthermore, genetic tests provide direction toward the most appropriate assisted reproductive techniques. Nevertheless, the use of molecular analysis in this field is still fragmented and cumbersome. The aim of this review is to highlight the conditions in which a genetic evaluation (counselling and testing) plays a role in improving the reproductive outcomes of infertile couples. We conducted a review of the literature, and starting from the observation of specific signs and symptoms, we describe the available molecular tests. To conceive a child, both partners' reproductive systems need to function in a precisely choreographed manner. Hence to treat infertility, it is key to assess both partners. Our results highlight the increasing importance of molecular testing in reproductive medicine.
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Affiliation(s)
| | - Valeria D'Argenio
- KronosDNA srl, Spinoff of Università Federico II, Naples, Italy.
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, 80131, Naples, Italy.
- CEINGE-Biotecnologie Avanzate scarl, Via Gaetano Salvatore 486, 80145, Naples, Italy.
| | - Rossella Tomaiuolo
- KronosDNA srl, Spinoff of Università Federico II, Naples, Italy
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, 80131, Naples, Italy
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12
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Nilsson D, Heglind M, Arani Z, Enerbäck S. Foxc2 is essential for podocyte function. Physiol Rep 2019; 7:e14083. [PMID: 31062503 PMCID: PMC6503019 DOI: 10.14814/phy2.14083] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 04/10/2019] [Accepted: 04/11/2019] [Indexed: 12/29/2022] Open
Abstract
Foxc2 is one of the earliest podocyte markers during glomerular development. To circumvent embryonic lethal effects of global deletion of Foxc2, and to specifically investigate the role of Foxc2 in podocytes, we generated mice with a podocyte-specific Foxc2 deletion. Mice carrying the homozygous deletion developed early proteinuria which progressed rapidly into end stage kidney failure and death around postnatal day 10. Conditional loss of Foxc2 in podocytes caused typical characteristics of podocyte injury, such as podocyte foot process effacement and podocyte microvillus transformation, probably caused by disruption of the slit diaphragm. These effects were accompanied by a redistribution of several proteins known to be necessary for correct podocyte structure. One target gene that showed reduced glomerular expression was Nrp1, the gene encoding neuropilin 1, a protein that has been linked to diabetic nephropathy and proteinuria. We could show that NRP1 was regulated by Foxc2 in vitro, but podocyte-specific ablation of Nrp1 in mice did not generate any phenotype in terms of proteinuria, suggesting that the gene might have more important roles in endothelial cells than in podocytes. Taken together, this study highlights a critical role for Foxc2 as an important gene for podocyte function.
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Affiliation(s)
- Daniel Nilsson
- Department of Medical Biochemistry and Cell BiologyInstitute of BiomedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Mikael Heglind
- Department of Medical Biochemistry and Cell BiologyInstitute of BiomedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Zahra Arani
- Department of Medical Biochemistry and Cell BiologyInstitute of BiomedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Sven Enerbäck
- Department of Medical Biochemistry and Cell BiologyInstitute of BiomedicineSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
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13
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WT1 Alternative Splicing: Role of Its Isoforms in Neuroblastoma. J Mol Neurosci 2017; 62:131-141. [DOI: 10.1007/s12031-017-0930-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/08/2017] [Indexed: 02/07/2023]
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14
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Repression of CMIP transcription by WT1 is relevant to podocyte health. Kidney Int 2016; 90:1298-1311. [PMID: 27650733 DOI: 10.1016/j.kint.2016.07.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 07/11/2016] [Accepted: 07/14/2016] [Indexed: 12/23/2022]
Abstract
The WT1 (Wilm's tumor suppressor) gene is expressed throughout life in podocytes and is essential for the functional integrity of the glomerular filtration barrier. We have previously shown that CMIP (C-Maf inducing protein) is overproduced in podocyte diseases and alters intracellular signaling. Here we isolated the proximal region of the human CMIP promoter and showed by chromatin immunoprecipitation assays and electrophoretic-mobility shift that Wilm's tumor protein (WT1) bound to 2 WT1 response elements, located at positions -290/-274 and -57/-41 relative to transcription start site. Unlike the human CMIP gene, only one Wt1 response element was identified in the mouse Cmip proximal promoter located at position -217/-206. Luciferase reporter assays indicated that WT1 dose-dependently inhibited the transcriptional induction of the CMIP promoter. Transfection of decoy oligonucleotides mimicking the WT1 response elements prevented the inhibition of WT1 on CMIP promoter activity. Furthermore, WT1 silencing promoted Cmip expression. In line with these findings, the abundance of Cmip was early and significantly increased at the transcript and protein level in podocytes displaying a primary defect in Wt1, including Denys-Drash syndrome and Frasier syndrome. Thus, WT1 is a major repressor of the CMIP gene in physiological situations, while conditional deletion of CMIP in the developing kidney did not affect the development of mature glomeruli.
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15
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Lehnhardt A, Karnatz C, Ahlenstiel-Grunow T, Benz K, Benz MR, Budde K, Büscher AK, Fehr T, Feldkötter M, Graf N, Höcker B, Jungraithmayr T, Klaus G, Koehler B, Konrad M, Kranz B, Montoya CR, Müller D, Neuhaus TJ, Oh J, Pape L, Pohl M, Royer-Pokora B, Querfeld U, Schneppenheim R, Staude H, Spartà G, Timmermann K, Wilkening F, Wygoda S, Bergmann C, Kemper MJ. Clinical and molecular characterization of patients with heterozygous mutations in wilms tumor suppressor gene 1. Clin J Am Soc Nephrol 2015; 10:825-31. [PMID: 25818337 DOI: 10.2215/cjn.10141014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 01/20/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVES The Wilms tumor suppressor gene 1 (WT1) plays an essential role in urogenital and kidney development. Genotype/phenotype correlations of WT1 mutations with renal function and proteinuria have been observed in world-wide cohorts with nephrotic syndrome or Wilms tumor (WT). This study analyzed mid-European patients with known constitutional heterozygous mutations in WT1, including patients without proteinuria or WT. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS Retrospective analysis of genotype, phenotype, and treatment of 53 patients with WT1 mutation from all pediatric nephrology centers in Germany, Austria, and Switzerland performed from 2010 to 2012. RESULTS Median age was 12.4 (interquartile range [IQR], 6-19) years. Forty-four of 53 (83%) patients had an exon mutation (36 missense, eight truncating), and nine of 53 (17%) had an intronic lysine-threonine-serine (KTS) splice site mutation. Fifty of 53 patients (94%) had proteinuria, which occurred at an earlier age in patients with missense mutations (0.6 [IQR, 0.1-1.5] years) than in those with truncating (9.7 [IQR, 5.7-11.9]; P<0.001) and splice site (4.0 [IQR, 2.6-6.6]; P=0.004) mutations. Thirteen of 50 (26%) were treated with steroids and remained irresponsive, while three of five partially responded to cyclosporine A. Seventy-three percent of all patients required RRT, those with missense mutations significantly earlier (at 1.1 [IQR, 0.01-9.3] years) than those with truncating mutations (16.5 [IQR, 16.5-16.8]; P<0.001) and splice site mutations (12.3 [IQR, 7.9-18.2]; P=0.002). Diffuse mesangial sclerosis was restricted to patients with missense mutations, while focal segmental sclerosis occurred in all groups. WT occurred only in patients with exon mutations (n=19). Fifty of 53 (94%) patients were karyotyped: Thirty-one (62%) had XY and 19 (38%) had XX chromosomes, and 96% of male karyotypes had urogenital malformations. CONCLUSIONS Type and location of WT1 mutations have predictive value for the development of proteinuria, renal insufficiency, and WT. XY karyotype was more frequent and associated with urogenital malformations in most cases.
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Affiliation(s)
- Anja Lehnhardt
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material.
| | - Claartje Karnatz
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Thurid Ahlenstiel-Grunow
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Kerstin Benz
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Marcus R Benz
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Klemens Budde
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Anja K Büscher
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Thomas Fehr
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Markus Feldkötter
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Norbert Graf
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Britta Höcker
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Therese Jungraithmayr
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Günter Klaus
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Birgit Koehler
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Martin Konrad
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Birgitta Kranz
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Carmen R Montoya
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Dominik Müller
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Thomas J Neuhaus
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Jun Oh
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Lars Pape
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Martin Pohl
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Brigitte Royer-Pokora
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Uwe Querfeld
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Reinhard Schneppenheim
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Hagen Staude
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Giuseppina Spartà
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Kirsten Timmermann
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Frauke Wilkening
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Simone Wygoda
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Carsten Bergmann
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
| | - Markus J Kemper
- Due to the number of contributing authors,the affiliations are provided in the Supplemental Material
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16
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Genetic causes of proteinuria and nephrotic syndrome: impact on podocyte pathobiology. Pediatr Nephrol 2015; 30:221-33. [PMID: 24584664 PMCID: PMC4262721 DOI: 10.1007/s00467-014-2753-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 12/31/2013] [Accepted: 01/02/2014] [Indexed: 12/11/2022]
Abstract
In the past 20 years, multiple genetic mutations have been identified in patients with congenital nephrotic syndrome (CNS) and both familial and sporadic focal segmental glomerulosclerosis (FSGS). Characterization of the genetic basis of CNS and FSGS has led to the recognition of the importance of podocyte injury to the development of glomerulosclerosis. Genetic mutations induce injury due to effects on the podocyte's structure, actin cytoskeleton, calcium signaling, and lysosomal and mitochondrial function. Transgenic animal studies have contributed to our understanding of podocyte pathobiology. Podocyte endoplasmic reticulum stress response, cell polarity, and autophagy play a role in maintenance of podocyte health. Further investigations related to the effects of genetic mutations on podocytes may identify new pathways for targeting therapeutics for nephrotic syndrome.
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17
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Glomerular development--shaping the multi-cellular filtration unit. Semin Cell Dev Biol 2014; 36:39-49. [PMID: 25153928 DOI: 10.1016/j.semcdb.2014.07.016] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 07/29/2014] [Accepted: 07/31/2014] [Indexed: 01/09/2023]
Abstract
The glomerulus represents a highly structured filtration unit, composed of glomerular endothelial cells, mesangial cells, podocytes and parietal epithelial cells. During glomerulogenesis an intricate network of signaling pathways involving transcription factors, secreted factors and cell-cell communication is required to guarantee accurate evolvement of a functional, complex 3-dimensional glomerular architecture. Here, we want to provide an overview on the critical steps and relevant signaling cascades of glomerular development.
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18
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Ozdemir DD, Hohenstein P. Wt1 in the kidney--a tale in mouse models. Pediatr Nephrol 2014; 29:687-93. [PMID: 24240471 DOI: 10.1007/s00467-013-2673-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 10/14/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
Abstract
The WT1 gene was originally identified through its involvement in the development of Wilms tumours. The gene is characterized by a plethora of different isoforms with, in some cases, clearly different functions in transcriptional control and RNA metabolism. Many different mouse models for Wt1 have already been generated, and these are increasingly providing new information on the molecular roles of Wt1 in normal development and disease. In this review we discuss the different models that have been generated and what they have taught us about the role of Wt1 in the kidney.
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Affiliation(s)
- Derya Deniz Ozdemir
- The Roslin Institute, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG, UK
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19
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Busch M, Schwindt H, Brandt A, Beier M, Görldt N, Romaniuk P, Toska E, Roberts S, Royer HD, Royer-Pokora B. Classification of a frameshift/extended and a stop mutation in WT1 as gain-of-function mutations that activate cell cycle genes and promote Wilms tumour cell proliferation. Hum Mol Genet 2014; 23:3958-74. [PMID: 24619359 PMCID: PMC4082364 DOI: 10.1093/hmg/ddu111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The WT1 gene encodes a zinc finger transcription factor important for normal kidney development. WT1 is a suppressor for Wilms tumour development and an oncogene for diverse malignant tumours. We recently established cell lines from primary Wilms tumours with different WT1 mutations. To investigate the function of mutant WT1 proteins, we performed WT1 knockdown experiments in cell lines with a frameshift/extension (p.V432fsX87 = Wilms3) and a stop mutation (p.P362X = Wilms2) of WT1, followed by genome-wide gene expression analysis. We also expressed wild-type and mutant WT1 proteins in human mesenchymal stem cells and established gene expression profiles. A detailed analysis of gene expression data enabled us to classify the WT1 mutations as gain-of-function mutations. The mutant WT1Wilms2 and WT1Wilms3 proteins acquired an ability to modulate the expression of a highly significant number of genes from the G2/M phase of the cell cycle, and WT1 knockdown experiments showed that they are required for Wilms tumour cell proliferation. p53 negatively regulates the activity of a large number of these genes that are also part of a core proliferation cluster in diverse human cancers. Our data strongly suggest that mutant WT1 proteins facilitate expression of these cell cycle genes by antagonizing transcriptional repression mediated by p53. We show that mutant WT1 can physically interact with p53. Together the findings show for the first time that mutant WT1 proteins have a gain-of-function and act as oncogenes for Wilms tumour development by regulating Wilms tumour cell proliferation.
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Affiliation(s)
- Maike Busch
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Heinrich Schwindt
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Artur Brandt
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Manfred Beier
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Nicole Görldt
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Paul Romaniuk
- Institute of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8P 5C2
| | - Eneda Toska
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA
| | - Stefan Roberts
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA
| | - Hans-Dieter Royer
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
| | - Brigitte Royer-Pokora
- Institute of Human Genetics and Anthropology, Heinrich-Heine University, Medical Faculty, Düsseldorf D-40225, Germany
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20
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Che R, Zhang A. Mechanisms of Glucocorticoid Resistance in Idiopathic Nephrotic Syndrome. ACTA ACUST UNITED AC 2013; 37:360-78. [DOI: 10.1159/000350163] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2013] [Indexed: 11/19/2022]
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21
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PAX2 in human kidney malformations and disease. Pediatr Nephrol 2012; 27:1265-75. [PMID: 22138676 DOI: 10.1007/s00467-011-2053-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Revised: 10/10/2011] [Accepted: 10/18/2011] [Indexed: 10/14/2022]
Abstract
Human PAX2 mutations have been associated with abnormalities in the developing and adult kidney ranging from congenital abnormalities of the kidney and urinary tract (CAKUT) to oncogenic processes. Defining the relationship of PAX2 to human renal disease requires an appreciation of its fundamental role in renal development. Given the highly conserved nature of the PAX2 gene in vertebrates, it is not surprising that much of our understanding of PAX2 involvement in renal disease has been derived from animal models. The following review will outline the current evidence supporting involvement of PAX2 in the pathologic processes involving the kidney.
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22
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Correa SM, Washburn LL, Kahlon RS, Musson MC, Bouma GJ, Eicher EM, Albrecht KH. Sex reversal in C57BL/6J XY mice caused by increased expression of ovarian genes and insufficient activation of the testis determining pathway. PLoS Genet 2012; 8:e1002569. [PMID: 22496664 PMCID: PMC3320579 DOI: 10.1371/journal.pgen.1002569] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 01/16/2012] [Indexed: 11/18/2022] Open
Abstract
Sex reversal can occur in XY humans with only a single functional WT1 or SF1 allele or a duplication of the chromosome region containing WNT4. In contrast, XY mice with only a single functional Wt1, Sf1, or Wnt4 allele, or mice that over-express Wnt4 from a transgene, reportedly are not sex-reversed. Because genetic background plays a critical role in testis differentiation, particularly in C57BL/6J (B6) mice, we tested the hypothesis that Wt1, Sf1, and Wnt4 are dosage sensitive in B6 XY mice. We found that reduced Wt1 or Sf1 dosage in B6 XY(B6) mice impaired testis differentiation, but no ovarian tissue developed. If, however, a Y(AKR) chromosome replaced the Y(B6) chromosome, these otherwise genetically identical B6 XY mice developed ovarian tissue. In contrast, reduced Wnt4 dosage increased the amount of testicular tissue present in Sf1+/- B6 XY(AKR), Wt1+/- B6 XY(AKR), B6 XY(POS), and B6 XY(AKR) fetuses. We propose that Wt1(B6) and Sf1(B6) are hypomorphic alleles of testis-determining pathway genes and that Wnt4(B6) is a hypermorphic allele of an ovary-determining pathway gene. The latter hypothesis is supported by the finding that expression of Wnt4 and four other genes in the ovary-determining pathway are elevated in normal B6 XX E12.5 ovaries. We propose that B6 mice are sensitive to XY sex reversal, at least in part, because they carry Wt1(B6) and/or Sf1(B6) alleles that compromise testis differentiation and a Wnt4(B6) allele that promotes ovary differentiation and thereby antagonizes testis differentiation. Addition of a "weak" Sry allele, such as the one on the Y(POS) chromosome, to the sensitized B6 background results in inappropriate development of ovarian tissue. We conclude that Wt1, Sf1, and Wnt4 are dosage-sensitive in mice, this dosage-sensitivity is genetic background-dependant, and the mouse strains described here are good models for the investigation of human dosage-sensitive XY sex reversal.
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Affiliation(s)
- Stephanie M. Correa
- Department of Medicine, Biomedical Genetics, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | | | - Ravi S. Kahlon
- Department of Medicine, Biomedical Genetics, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Michelle C. Musson
- Department of Medicine, Biomedical Genetics, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Gerrit J. Bouma
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Eva M. Eicher
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Kenneth H. Albrecht
- Department of Medicine, Biomedical Genetics, Boston University School of Medicine, Boston, Massachusetts, United States of America
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- * E-mail:
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Sahali D, Audard V, Rémy P, Lang P. [Pathogenesis and treatment of idiopathic nephrotic syndrome in adults]. Nephrol Ther 2012; 8:180-92. [PMID: 22425458 DOI: 10.1016/j.nephro.2011.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Idiopathic nephrotic syndrome is the most frequent glomerular disease in children and in young adults. While genetic analyses have provided new insights into disease pathogenesis through the discovery of several podocyte genes mutated in distinct forms of inherited nephrotic syndrome, the molecular bases of minimal change nephrotic syndrome and focal and segmental glomerulosclerosis with relapses remain unclear. Although immune cell disorders, which may involve both innate and adaptive immunity, appear to play a role in the pathogenesis of steroid sensitive minimal change nephrotic syndrome, the mechanisms by which they induce podocyte dysfunction remain unresolved. It was postulated that podocyte injury results from a circulating factor secreted by abnormal T cells, but the possibility that bipolarity of the disease results from a functional disorder shared by both immune cells and the podocytes is not excluded. Minimal change nephrotic syndrome relapses are associated with an expansion of T and B cell compartments and production of growth factors as well as many cytokines. Dysfunction of T cells is supported by several findings including, inhibition of a type IV hypersensitivity reaction and unclassical T helper polarization, resulting from transcriptional interference between Th1 and Th2 transcriptional factors. A low serum level of some IgG fractions is frequently observed suggesting a defect in T-B cell cooperation, which remains to be explored. In this review, we discuss recent advances in the pathogenesis and the therapy of idiopathic nephrotic syndrome.
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Affiliation(s)
- Dil Sahali
- Service de néphrologie, centre hospitalier universitaire Henri-Mondor, Créteil, France.
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Miller-Hodges E, Hohenstein P. WT1 in disease: shifting the epithelial-mesenchymal balance. J Pathol 2011; 226:229-40. [PMID: 21959952 DOI: 10.1002/path.2977] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 07/07/2011] [Accepted: 07/23/2011] [Indexed: 12/13/2022]
Abstract
WT1 is a versatile gene that controls transitions between the mesenchymal and epithelial state of cells in a tissue-context dependent manner. As such, WT1 is indispensable for normal development of many organs and tissues. Uncontrolled epithelial to mesenchymal transition (EMT) is a hallmark of a diverse array of pathologies and disturbance of mesenchymal to epithelial transition (MET) has been associated with a number of developmental abnormalities. It is therefore not surprising that WT1 has been linked to many of these. Here we review the role of WT1 in proper control of the mesenchymal-epithelial balance of cells and discuss how far these roles can explain the role of WT1 in a variety of disease states.
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Affiliation(s)
- Eve Miller-Hodges
- MRC Human Genetics Unit and Institute for Genetics and Molecular Medicine, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
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25
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Owen C, Fitzgibbon J, Paschka P. The clinical relevance of Wilms Tumour 1 (WT1) gene mutations in acute leukaemia. Hematol Oncol 2010; 28:13-9. [PMID: 20013787 DOI: 10.1002/hon.931] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recurrent genetic aberrations are important predictors of outcome in acute myeloid leukaemia (AML). Numerous novel molecular abnormalities have been identified and investigated in recent years adding to the risk stratification and prognostication of conventional karyotyping. Mutations in the Wilms Tumour 1 (WT1) gene were first described more than a decade ago but their clinical significance has only recently been evaluated. WT1 mutations occur in approximately 10% of adult AML patients at diagnosis and are most frequent in the cytogenetically normal (CN) AML subgroup. These mutations appear to confer a negative prognostic outcome by increasing the risk of relapse and death. Mutation frequency is higher in pediatric patients and also appears to confer a negative impact on relapse and survival. Herein, we discuss the importance of WT1 mutations in AML.
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Affiliation(s)
- Carolyn Owen
- Division of Hematology and Hematological Malignancies, University of Calgary, 601A South Tower, Foothills Medical Centre, 1403-29th Street NW, Calgary, Alberta, T2N 2T9, Canada.
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Andrade JGRD, Guaragna MS, Soardi FC, Guerra-Júnior G, Mello MPD, Maciel-Guerra AT. Clinical and genetic findings of five patients with WT1-related disorders. ACTA ACUST UNITED AC 2009; 52:1236-43. [PMID: 19169475 DOI: 10.1590/s0004-27302008000800006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 10/14/2008] [Indexed: 11/22/2022]
Abstract
AIM To present phenotypic variability of WT1-related disorders. METHODS Description of clinical and genetic features of five 46,XY patients with WT1 anomalies. RESULTS Patient 1: newborn with genital ambiguity; he developed Wilms tumor (WT) and chronic renal disease and died at the age of 10 months; the heterozygous 1186G>A mutation compatible with Denys-Drash syndrome was detected in this child. Patients 2 and 3: adolescents with chronic renal disease, primary amenorrhea and hypergonadotrophic hypogonadism; patient 2 had a gonadoblastoma. The heterozygous IVS9+4, C>T mutation, compatible with Frasier syndrome was detected. Patient 4: 9-year-old boy with aniridia, genital ambiguity, dysmorphisms and mental deficiency; a heterozygous 11p deletion, compatible with WAGR syndrome was detected. Patient 5: 2 months old, same diagnosis of patient 4; he developed WT at the age of 8 months. CONCLUSIONS Constitutional abnormalities of WT1 cause gonadal and renal anomalies and predisposition to neoplasia and must be investigated in patients with ambiguous genitalia, chronic renal disease and(or) Wilms tumors; primary amenorrhea with chronic renal disease; and aniridia, genital ambiguity and dysmorphisms.
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Auber F, Jeanpierre C, Denamur E, Jaubert F, Schleiermacher G, Patte C, Cabrol S, Leverger G, Nihoul-Fékété C, Sarnacki S. Management of Wilms tumors in Drash and Frasier syndromes. Pediatr Blood Cancer 2009; 52:55-9. [PMID: 18816692 DOI: 10.1002/pbc.21759] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Children with WT1 gene-related disorders such as Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are at increased risk of Wilms tumor and end-stage renal disease. We investigated whether Wilms tumors in these patients displayed a specific phenotype or behavior and whether nephron-sparing surgery was beneficial. PROCEDURE We retrospectively studied all patients with DDS, FS, or other WT1 mutations treated at our institutions between 1980 and 2007. RESULTS We identified 20 patients, of whom 18 had benign or malignant tumors. Wilms tumors occurred in 15 patients, being unilateral in 10 and bilateral in 5 (20 tumors). Median age at Wilms tumor diagnosis was 9 months. No patients had metastases. According to the International Society of Pediatric Oncology Working Classification, there were 19 intermediate-risk tumors and one high-risk tumor; no tumor was anaplastic. In patients with nephropathy who underwent unilateral nephrectomy for Wilms tumor or nephron-sparing surgery for bilateral Wilms tumor, mean time to dialysis was 11 or 9 months, respectively. Other tumors included three gonadoblastomas (in two patients), one retroperitoneal soft-tissue tumor, and one transitional cell papilloma of the bladder. Two patients, both with stage I Wilms tumor, died from end-stage renal disease-related complications. The median follow-up time for the 18 survivors was 136 months (range, 17-224 months). CONCLUSION Most Wilms tumors in children with WT1-related disorders were early-stage and intermediate-risk tumors, with a young age at diagnosis. In patients without end-stage renal disease, nephron-sparing surgery should be considered for delaying the onset of renal failure.
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Affiliation(s)
- F Auber
- Department of Pediatric Surgery, AP-HP, Hôpital Armand Trousseau, Paris, France.
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Morrison AA, Viney RL, Saleem MA, Ladomery MR. New insights into the function of the Wilms tumor suppressor gene WT1 in podocytes. Am J Physiol Renal Physiol 2008; 295:F12-7. [DOI: 10.1152/ajprenal.00597.2007] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Wilms tumor suppressor gene WT1 is essential for early urogenital development: homozygous mutations in WT1 result in embryonic lethality due to a failure in the development of kidneys and gonads. In the adult kidney, WT1 expression is limited to the glomerular podocytes. Several human nephrotic diseases arise from mutations of the WT1 gene, including mutations that affect its zinc-fingers and alternative splicing of +/−KTS isoforms. These include WAGR (for Wilms tumor, aniridia, genitourinary anomalies, and mental retardation), and Frasier and Denys-Drash syndromes. Recent advances including the development of transgenic mouse models and conditionally immortalized podocyte cell lines are beginning to shed light on WT1's crucial role in podocyte function.
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Virappane P, Gale R, Hills R, Kakkas I, Summers K, Stevens J, Allen C, Green C, Quentmeier H, Drexler H, Burnett A, Linch D, Bonnet D, Lister TA, Fitzgibbon J. Mutation of the Wilms' tumor 1 gene is a poor prognostic factor associated with chemotherapy resistance in normal karyotype acute myeloid leukemia: the United Kingdom Medical Research Council Adult Leukaemia Working Party. J Clin Oncol 2008; 26:5429-35. [PMID: 18591546 DOI: 10.1200/jco.2008.16.0333] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PURPOSE To determine the clinical relevance of Wilms' tumor 1 (WT1) gene mutations in acute myeloid leukemia (AML) with normal karyotype (NK). PATIENTS AND METHODS Exons 7 and 9 of WT1 were screened in samples from 470 young adult NK AMLs using a combination of direct sequencing and high-resolution capillary electrophoresis. RESULTS Overall, 51 mutations were detected in 47 cases (10%): 46 frameshift mutations with insertion/deletion of one to 28 base pairs in exon 7 (n = 45) or exon 9 (n = 1), with a median mutant level of 45% (range, 8% to 86%), and five substitutions in exon 9: D396N (n = 3), H397Y (n = 1) and H397Q (n = 1). Patients with WT1 mutations had an inferior response to induction chemotherapy compared with wild-type cases (complete remission rate, 79% v 90%, odds ratio [OR] = 3.02; 95% CI, 1.17 to 7.82; P = .02), a higher rate of resistant disease (15% v 4%; OR = 9.33; 95% CI, 2.38 to 36.6; P = .001), an increased cumulative incidence of relapse (67% v 43%, hazard ratio [HR] = 3.02; 95% CI, 1.69 to 5.38; P = .0008), with a reduction in both relapse-free survival (22% v 44%; HR = 2.16; 95% CI, 1.32 to 3.55; P = .005) and overall survival (26% v 47%; HR = 1.91; 95% CI, 1.23 to 2.95; P = .007) at 5 years. In multivariate analysis, which included FLT3 internal tandem duplication and NPM1 mutation status, the presence of a WT1 mutation remained an independent adverse prognostic factor. CONCLUSION WT1 mutations are a negative prognostic indicator in NK AML and may be suitable for the development of targeted therapy.
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Affiliation(s)
- Priya Virappane
- Centre for Medical Oncology, Institute of Cancer, Barts and the London School of Medicine, Charterhouse Square, London, UK
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Steege A, Fähling M, Paliege A, Bondke A, Kirschner KM, Martinka P, Kaps C, Patzak A, Persson PB, Thiele BJ, Scholz H, Mrowka R. Wilms' tumor protein (-KTS) modulates renin gene transcription. Kidney Int 2008; 74:458-66. [PMID: 18496514 DOI: 10.1038/ki.2008.194] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Renin plays a crucial role in the control of various physiological processes such as blood pressure and body fluid homeostasis. Here, we show that a splice variant of the Wilms' tumor protein lacking three amino acids WT1(-KTS) suppresses renin gene transcription. Using bioinformatics tools, we initially predicted that a WT1-binding site exists in a regulatory region about 12 kb upstream of the renin promoter; this was confirmed by reporter gene assays and gel shift experiments in heterologous cells. Co-expression of Wt1 and renin proteins was found in rat kidney sections, mouse kidney blood vessels, and a cell line derived from the juxtaglomerular apparatus that produces renin. Knockdown of WT1 protein by siRNA significantly increased the cellular renin mRNA content, while overexpression of WT1(-KTS) reduced renin gene expression in stable and transiently transfected cells. A mutant WT1(-KTS) protein found in Wilms' tumors failed to suppress renin gene reporter activity and endogenous renin expression. Our findings show that renin gene transcription is regulated by the WT1(-KTS) protein and this may explain findings in patients with WT1 gene mutations of increased plasma renin and hypertension.
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Affiliation(s)
- Andreas Steege
- Institut für Physiologie CCM, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Waters AM, Wu MYJ, Onay T, Scutaru J, Liu J, Lobe CG, Quaggin SE, Piscione TD. Ectopic notch activation in developing podocytes causes glomerulosclerosis. J Am Soc Nephrol 2008; 19:1139-57. [PMID: 18337488 DOI: 10.1681/asn.2007050596] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Genetic evidence supports an early role for Notch signaling in the fate of podocytes during glomerular development. Decreased expression of Notch transcriptional targets in developing podocytes after the determination of cell fate suggests that constitutive Notch signaling may oppose podocyte differentiation. This study determined the effects of constitutive Notch signaling on podocyte differentiation by ectopically expressing Notch's intracellular domain (NOTCH-IC), the biologically active, intracellular product of proteolytic cleavage of the Notch receptor, in developing podocytes of transgenic mice. Histologic and molecular analyses revealed normal glomerular morphology and expression of podocyte markers in newborn NOTCH-IC-expressing mice; however, mice developed severe proteinuria and showed evidence of progressive glomerulosclerosis at 2 wk after birth. Features of mature podocytes were lost: Foot processes were effaced; expression of Wt1, Nphs1, and Nphs2 was downregulated; cell-cycle re-entry was induced; and the expression of Pax2 was increased. In contrast, mice with podocyte-specific inactivation of Rbpsuh, which encodes a protein essential for canonical Notch signaling, seemed normal. In addition, the damaging effects of NOTCH-IC expression were prevented in transgenic mice after simultaneous conditional inactivation of Rbpsuh in murine podocytes. These results suggest that Notch signaling is dispensable during terminal differentiation of podocytes but that constitutive (or inappropriate) Notch signaling is deleterious, leading to glomerulosclerosis.
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Affiliation(s)
- Aoife M Waters
- Program in Developmental Biology, Research Institute, and Division of Nephrology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
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Patek CE, Brownstein DG, Fleming S, Wroe C, Rose L, Webb A, Berry RL, Devenney PS, Walker M, Maddocks ODK, Lawrence NJ, Harrison DJ, Wood KM, Miles CG, Hooper ML. Effects on kidney disease, fertility and development in mice inheriting a protein-truncating Denys-Drash syndrome allele (Wt1tmT396). Transgenic Res 2007; 17:459-75. [PMID: 18040647 DOI: 10.1007/s11248-007-9157-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Accepted: 11/06/2007] [Indexed: 12/01/2022]
Abstract
Denys-Drash syndrome (DDS) is caused by heterozygous mutations of the Wilms' tumour suppressor gene, WT1, characterised by early-onset diffuse mesangial sclerosis often associated with male pseudohermaphroditism and/or Wilms' tumourigenesis. Previously, we reported that the Wt1tmT396 allele induces DDS kidney disease in mice. In the present study heterozygotes (Wt1tmT396/+) were generated on inbred (129/Ola), crossbred (B6/129) and MF1 second backcross (MF1-N2) backgrounds. Whereas male heterozygotes on each background were fertile, inbred heterozygous females were infertile. Kidney disease (proteinuria and sclerosis) was not congenital and developed significantly earlier in inbred mice, although with variable onset. Disease onset in MF1-N2 stocks occurred later in Wt1tmT396/+ mice than reported previously for Wt1R394W/+ mice, and while no kidney disease has been reported in B6/129 Wt1+/- mice, B6/129 Wt1tmT396/+ mice were affected. Offspring of both male and female B6/129 and MF1-N2 Wt1tmT396/+ mice developed kidney disease, but its incidence was significantly higher in offspring of female heterozygotes. Wt1tmT396/tmT396 embryos exhibited identical developmental abnormalities to those reported for Wt1-/- embryos. The results indicate that the Wt1 (tmT396) allele does not predispose to Wilms' tumourigenesis or male pseudohermaphroditism, its effect on kidney disease and female fertility depends on genetic background, stochastic factors may affect disease onset, and disease transmission is subject to a partial parent-of-origin effect. Since the Wt1tmT396 allele has no detectable intrinsic functional activity in vivo, and kidney disease progression is affected by the type of Wt1 mutation, the data support the view that DDS nephropathy results from a dominant-negative action rather than WT1 haploinsufficiency or gain-of-function.
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Affiliation(s)
- Charles E Patek
- Sir Alastair Currie Cancer Research UK Laboratories, Molecular Medicine Centre, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
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Rascle A, Suleiman H, Neumann T, Witzgall R. Role of transcription factors in podocytes. Nephron Clin Pract 2007; 106:e60-6. [PMID: 17570941 DOI: 10.1159/000101794] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Despite a wealth of information on structural proteins, comparatively little is known on the transcriptional regulation of podocyte structure and function. In this review we will highlight those transcription factors which, by gene inactivation or classical transgenic experiments, have been shown to be essential for podocytes or probably will turn out to be so. The tumor suppressor protein WT1 is not only indispensable for the initial stages of kidney development, but also very likely maintains the integrity of the fully differentiated podocyte. In the kidney, the LIM homeodomain transcription factor LMX1B is specifically synthesized in podocytes, and mutations in LMX1B lead to nail-patella syndrome and the associated nephropathy. Other transcription factors such as hypoxia-inducible factors and PAX2 are likely to play a role in podocytes, whereas the significance of others, e.g. of POD1 and CITED2, is more speculative at this point.
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Affiliation(s)
- Anne Rascle
- Institute for Molecular and Cellular Anatomy, University of Regensburg, Regensburg, Germany
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35
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Le Caignec C, Delnatte C, Vermeesch JR, Boceno M, Joubert M, Lavenant F, David A, Rival JM. Complete sex reversal in a WAGR syndrome patient. Am J Med Genet A 2007; 143A:2692-5. [DOI: 10.1002/ajmg.a.31997] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
The WT1 gene encodes a zinc finger transcription factor involved in kidney and gonadal development and, when mutated, in the occurrence of kidney tumor and glomerular diseases. Patients with Denys-Drash syndrome present with early nephrotic syndrome with diffuse mesangial sclerosis progressing rapidly to end-stage renal failure, male pseudohermaphroditism, and Wilms' tumor. Incomplete forms of the syndrome have been described. Germline WT1 missense mutations located in exons 8 or 9 coding for zinc fingers 2 or 3 have been detected in nearly all patients with Denys-Drash syndrome and in some patients with isolated diffuse mesangial sclerosis. Patients with Frasier syndrome present with normal female external genitalia, streak gonads, XY karyotype and progressive nephropathy with proteinuria and nephrotic syndrome with focal and segmental glomerular sclerosis progressing to end-stage renal disease in adolescence or young adulthood. They frequently develop gonadoblastoma. Germline intronic mutations leading to the loss of the +KTS isoforms have been observed in all patients with Frasier syndrome. The same mutations have been observed in genetically female patients with isolated FSGS. Transmission of the mutation is possible. Frasier mutations have also been reported in children with Denys-Drash syndrome.
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Affiliation(s)
- Patrick Niaudet
- Service de Néphrologie Pédiatrique and INSERM U574, Hôpital Necker-Enfants Malades, 149 rue de Sévres, 75743, Paris, Cedex 15, France.
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Jaffe JA, Kimmel PL. Chronic nephropathies of cocaine and heroin abuse: a critical review. Clin J Am Soc Nephrol 2006; 1:655-67. [PMID: 17699270 DOI: 10.2215/cjn.00300106] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Renal disease in cocaine and heroin users is associated with the nephrotic syndrome, acute glomerulonephritis, amyloidosis, interstitial nephritis, and rhabdomyolysis. The pathophysiologic basis of cocaine-related renal injury involves renal hemodynamic changes, glomerular matrix synthesis and degradation, and oxidative stress and induction of renal atherogenesis. Heroin is the most commonly abused opiate in the United States. Previous studies identified a spectrum of renal diseases in heroin users. The predominant renal lesion in black heroin users is focal segmental glomerulosclerosis and in white heroin users is membranoproliferative glomerulonephritis. Although the prevalence of heroin use in the United States has increased, the incidence of "heroin nephropathy" has declined. Because reports of heroin nephropathy predated the surveillance of hepatitis C virus and HIV, the varied findings might be related to the spectrum of viral illnesses that are encountered in injection drug users. Socioeconomic conditions, cultural and behavioral practices, or differences in genetic susceptibilities may be more associated with the development of nephropathy in heroin users than the drug's pharmacologic properties. Administration of cocaine in animal models results in nonspecific glomerular, interstitial, and tubular cell lesions, but there is no animal model of heroin-associated renal disease. The heterogeneity of responses that are associated with heroin is not consistent with a single or simple notion of nephropathogenesis. There are no well-designed, prospective, epidemiologic studies to assess the incidence and the prevalence of renal disease in populations of opiate users and to establish the validity of a syndrome such as heroin nephropathy. It is concluded although there is a paucity of evidence to support a heroin-associated nephropathy, the evidence from in vitro cellular and animal studies to support the existence of cocaine-induced renal changes is more convincing.
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Affiliation(s)
- Jared A Jaffe
- Division of Renal Diseases and Hypertension, Department of Medicine, George Washington University Medical Center, 2150 Pennsylvania Avenue NW, Washington, DC 20037, USA
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38
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Patek CE, Saunders PTK, Miles CG, Berry RL, Hastie ND, Sharpe RM, Hooper ML. Gonadal effects of a mouse Denys-Drash syndrome mutation. Transgenic Res 2006; 14:691-702. [PMID: 16245160 DOI: 10.1007/s11248-005-7216-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Accepted: 05/11/2005] [Indexed: 10/25/2022]
Abstract
Gonadal effects of the Denys-Drash syndrome (DDS) mutation Wt1(tmT396 )were examined in chimaeric and heterozygous mice. Since the only heterozygote was 41,XXY, Sertoli cell function was assessed by comparison with age-matched control XXY testes. Control XXY Sertoli cells showed immuno-expression of WT1 and androgen receptor (AR) indistinguishable from wild-type (40,XY), but expressed anti-Mullerian hormone (AMH). In contrast, DDS Sertoli cells showed only faint immuno-expression of WT1 and did not express AR or AMH. While XY<-->XY DDS chimaeras were male, XX<-->XY chimaeras were predominantly female. In the rare XX<-->XY DDS males the Sertoli cell lineage was largely derived from Wt1 mutant XY cells. We conclude that DDS mutant cells can form Sertoli cells, that the dominant mutation does not cause male sex reversal in mice but distorts the sex ratio of XX<-->XY chimaeras, and that there may be a link between WT1, AMH and AR expression by Sertoli cells in vivo.
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Affiliation(s)
- C E Patek
- Sir Alastair Currie Cancer Research UK Laboratories, Molecular Medicine Centre, Western General Hospital, Crewe Road, EH4 2XU Edinburgh, UK
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39
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Lahiri D, Dutton JR, Duarte A, Moorwood K, Graham CF, Ward A. Nephropathy and defective spermatogenesis in mice transgenic for a single isoform of the Wilms' tumour suppressor protein, WT1−KTS, together with one disruptedWt1 Allele. Mol Reprod Dev 2006; 74:300-11. [PMID: 16967512 DOI: 10.1002/mrd.20491] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The Wilms' tumour suppressor protein, WT1, is a zinc finger protein essential for the development of several organs, including the kidney and gonads. In each of these tissues WT1 is required at multiple stages of development and its persistent expression in podocytes and Sertoli cells suggests WT1 may also have a role in the maintenance of kidney and testis function throughout adult life. Naturally occurring isoforms of WT1 are generated by alternative mRNA splicing. An altered ratio of the splice isoforms WT1-KTS and WT1 + KTS appears to be sufficient to account for the developmental abnormalities (pseudohermaphroditism and nephropathy) characteristic of Frasier syndrome. We show that mice with a transgene encoding WT1-KTS do not differ from their wild-type littermates unless they are also heterozygous for a null mutation at the endogenous Wt1 locus. Animals with both genetic modifications develop proteinuria, together with multiple glomerular cysts, and male infertility. These pathologic changes may be explained as a consequence of altering the WT1 isoform ratio in tissues that express WT1 during adulthood. The results suggest WT1 misexpression could contribute to human glomerulocystic kidney disease.
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Affiliation(s)
- Diya Lahiri
- Department of Biology & Biochemistry, Centre for Regenerative Medicine and Developmental Biology Program, University of Bath, Bath, UK
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40
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Breslow NE, Collins AJ, Ritchey ML, Grigoriev YA, Peterson SM, Green DM. End stage renal disease in patients with Wilms tumor: results from the National Wilms Tumor Study Group and the United States Renal Data System. J Urol 2005; 174:1972-5. [PMID: 16217371 PMCID: PMC1483840 DOI: 10.1097/01.ju.0000176800.00994.3a] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE We sought to assess accurately the full spectrum of end stage renal disease (ESRD) in Wilms tumor survivors by combining the unique resources of the National Wilms Tumor Study Group (NWTSG) and the United States Renal Data System (USRDS), and to confirm preliminary reports of an increased incidence of ESRD in patients with the Wilms tumor-aniridia syndrome (WAGR). MATERIALS AND METHODS ESRD was ascertained in 5,910 patients enrolled in NWTSG studies during 1969 to 1994 by record linkage to USRDS and by direct followup. Cumulative ESRD incidence was estimated accounting for intercurrent mortality. RESULTS Of 115 cases of ESRD 10 (9%) were ascertained by the NWTSG alone, 13 (11%) by USRDS alone and 92 (80%) by both. Cumulative incidence of ESRD at 20 years from diagnosis of unilateral Wilms tumor was 74% for 17 patients with the Denys-Drash syndrome, 36% for 37 patients with WAGR, 7% for 125 male patients with hypospadias or cryptorchidism (genitourinary [GU] anomalies) and 0.6% for 5,347 patients with none of these conditions. The incidence of ESRD after diagnosis of bilateral Wilms tumor was 50% for the Denys-Drash syndrome (6 patients), 90% for WAGR (10), 25% for GU anomaly (25) and 12% for other (409). ESRD in patients with WAGR or GU anomalies tended to occur relatively late, often during or after adolescence. CONCLUSIONS The risk of ESRD is remarkably low for the majority of patients with Wilms tumor. However, those with WAGR or associated GU anomalies are at higher risk and should be screened indefinitely to facilitate prospective treatment of impaired renal function.
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Affiliation(s)
- Norman E Breslow
- Department of Biostatistics, University of Washington, Fred Hutchinson Cancer Research Center, Seattle, Washington 98195-7232, USA.
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41
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Abstract
Wilms' tumour, or nephroblastoma, is a common childhood tumour that is intimately linked to early kidney development and is often associated with persistent embryonic renal tissue and other kidney abnormalities. WT1, the first gene found to be inactivated in Wilms' tumour, encodes a transcription factor that functions as both a tumour suppressor and a critical regulator of renal organogenesis. Our understanding of the roles of WT1 in tumour formation and organogenesis have advanced in parallel, providing a striking example of the intersection between tumour biology, cellular differentiation and normal organogenesis.
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Affiliation(s)
- Miguel N Rivera
- Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, Massachusetts 02129, USA.
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Abstract
Wilms’ tumor (nephroblastoma) represents a unique example of an aberrant kidney formation that can result from mutations in a tumor suppressor gene, Wilms’ tumor 1 ( WT1). Targeted gene inactivation in mice testifies that WT1 is a master switch for the development of the genitourinary system and other organs.
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Affiliation(s)
- Holger Scholz
- Johannes-Müller-Institut für Physiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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43
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Orloff MS, Iyengar SK, Winkler CA, Goddard KAB, Dart RA, Ahuja TS, Mokrzycki M, Briggs WA, Korbet SM, Kimmel PL, Simon EE, Trachtman H, Vlahov D, Michel DM, Berns JS, Smith MC, Schelling JR, Sedor JR, Kopp JB. Variants in the Wilms' tumor gene are associated with focal segmental glomerulosclerosis in the African American population. Physiol Genomics 2005; 21:212-21. [PMID: 15687485 DOI: 10.1152/physiolgenomics.00201.2004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Wilms' tumor gene (WT1) is important for nephrogenesis and gonadal growth. WT1 mutations cause Denys-Drash and Frasier syndromes, which are characterized by glomerular scarring. To test whether genetic variations in WT1 and WIT1 (gene immediately 5' to WT1) associate with focal segmental glomerulosclerosis (FSGS), patients with biopsy-proven idiopathic and HIV-1-associated FSGS were enrolled in a multicenter study. We genotyped SNP rs6508 located in WIT1 exon 1, three SNPs (rs2301250, rs2301252, rs2301254) in the promoter shared by WT1 and WIT1, rs2234590 in exon 6, rs2234591 in intron 6, rs16754 in exon 7, and rs1799937 in intron 9 of WT1. Cases (n = 218) and controls (n = 281) were compared in the African American population. Stratification by HIV-1 infection status showed that SNPs rs6508, rs2301254, and rs1799937 were significantly associated with FSGS [rs6508 odds ratio (OR) 1.82, P = 0.006; rs2301254 OR 1.65, P = 0.049; rs1799937 OR 1.91, P = 0.005] in the non-HIV-1 group and rs2234591 (OR 0.234, P = 0.011) in the HIV-1 group. Haplotype analyses in the population revealed that seven SNPs were associated with FSGS; five SNPs had the highest contingency score [-log10(P value) = 13.57] in the HIV-1 group. This association could not be explained by population substructure. We conclude that SNPs in WT1 and WIT1 genes are significantly associated with FSGS, suggesting that variants in these genes may mediate pathogenesis by altering WT1 function. Furthermore, HIV-1 infection status interacts with genetic variations in both genes to influence this phenotype. We speculate that nephropathy liability alleles in WT1 pathway genes cause podocyte dysfunction and glomerular scarring.
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Affiliation(s)
- Mohammed S Orloff
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio 44106-7281, USA
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Klonisch T, Fowler PA, Hombach-Klonisch S. Molecular and genetic regulation of testis descent and external genitalia development. Dev Biol 2004; 270:1-18. [PMID: 15136137 DOI: 10.1016/j.ydbio.2004.02.018] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Revised: 01/18/2004] [Accepted: 02/17/2004] [Indexed: 12/27/2022]
Abstract
Testicular descent as a prerequisite for the production of mature spermatozoa and normal external genitalia morphogenesis, and therefore facilitating copulation and internal fertilization, are essential developmental steps in reproduction of vertebrate species. Cryptorchidism, the failure of testis descent, and feminization of external genitalia in the male, usually in the form of hypospadias, in which the opening of the urethra occurs along the ventral aspect of the penis, are the most frequent pediatric complications. Thus, elucidating the molecular mechanisms involved in the regulation of testis descent and the formation of external genitalia merits a special focus. Natural and transgenic rodent models have demonstrated both morphogenic processes to be under the control of a plethora of genetic factors with complex time-, space-, and dose-restricted expression pattern. The review elucidates the molecular mechanisms involved in the regulation of testis descent and the formation of external genitalia and, wherever possible, assesses the differences between these rodent animal models and other mammalian species, including human.
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Affiliation(s)
- Thomas Klonisch
- Department of Anatomy and Cell Biology, Medical Faculty, Martin Luther University of Halle-Wittenberg, Halle/Saale, Germany.
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45
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Yang AH, Chen JY, Chen BF. The dysregulated glomerular cell growth in Denys-Drash syndrome. Virchows Arch 2004; 445:305-14. [PMID: 15232745 DOI: 10.1007/s00428-004-1069-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2004] [Accepted: 05/28/2004] [Indexed: 11/25/2022]
Abstract
While diffuse mesangial sclerosis is traditionally described as being the glomerulopathy of Denys-Drash syndrome (DDS), the podocyte proliferative lesions may be overlooked in these DDS cases. In the present study, an evolving process is extrapolated from a selected case of DDS that demonstrated glomerulopathy with conspicuous podocyte proliferation. The observation that podocytes express proliferation markers (Ki67, proliferating-cell nuclear antigen and topoisomerase IIalpha) in non-proliferative, mature-looking glomeruli suggests an initial pathogenic act to activate or to keep podocytes from quiescence. The subsequent proliferation of podocytes is in keeping with downregulation of WT1 and cyclin kinase inhibitors of p16 and p21. The emergence of cytokeratin-positive cells in glomeruli that show typical mesangial sclerosis implies elimination of podocytes and replacement with tubular and/or parietal epithelial cells. The final scene of evolving glomerulopathy displays apoptosis and expression of Fas-L and Bax in sclerotic mesangial lesions, which eventually end up with global sclerosis. This novel concept of DDS glomerulopathy implies complex molecular mechanisms involved in glomerular injury.
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Affiliation(s)
- An Hang Yang
- Ultrastructural and Molecular Pathology, Department of Pathology, Taipei Veterans General Hospital, Taipei, Taiwan.
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Xing Y, Resch A, Lee C. The multiassembly problem: reconstructing multiple transcript isoforms from EST fragment mixtures. Genome Res 2004; 14:426-41. [PMID: 14962984 PMCID: PMC353230 DOI: 10.1101/gr.1304504] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2003] [Accepted: 12/01/2003] [Indexed: 12/28/2022]
Abstract
Recent evidence of abundant transcript variation (e.g., alternative splicing, alternative initiation, alternative polyadenylation) in complex genomes indicates that cataloging the complete set of transcripts from an organism is an important project. One challenge is the fact that most high-throughput experimental methods for characterizing transcripts (such as EST sequencing) give highly detailed information about short fragments of transcripts or protein products, instead of a complete characterization of a full-length form. We analyze this "multiassembly problem"-reconstructing the most likely set of full-length isoform sequences from a mixture of EST fragment data-and present a graph-based algorithm for solving it. In a variety of tests, we demonstrate that this algorithm deals appropriately with coupling of distinct alternative splicing events, increasing fragmentation of the input data and different types of transcript variation (such as alternative splicing, initiation, polyadenylation, and intron retention). To test the method's performance on pure fragment (EST) data, we removed all mRNA sequences, and found it produced no errors in 40 cases tested. Using this algorithm, we have constructed an Alternatively Spliced Proteins database (ASP) from analysis of human expressed and genomic sequences, consisting of 13,384 protein isoforms of 4422 genes, yielding an average of 3.0 protein isoforms per gene.
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Affiliation(s)
- Yi Xing
- UCLA-DOE Center for Genomics and Proteomics, Molecular Biology Institute and Department of Chemistry & Biochemistry, University of California, Los Angeles, Los Angeles, California 90095-1570, USA
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Discenza MT, Pelletier J. Insights into the physiological role of WT1 from studies of genetically modified mice. Physiol Genomics 2004; 16:287-300. [PMID: 14966251 DOI: 10.1152/physiolgenomics.00164.2003] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Discenza, Maria Teresa, and Jerry Pelletier. Insights into the physiological role of WT1 from studies of genetically modified mice. Physiol Genomics 16: 287-300, 2004; 10.1152/physiolgenomics.00164.2003.—The identification of WT1 gene mutations in children with WAGR and Denys-Drash syndromes pointed toward a role for WT1 in genitourinary system development. Biochemical analysis of the different WT1 protein isoforms showed that WT1 is a transcription factor and also has the ability to bind RNA. Analysis of WT1 complexes identified several target genes and protein partners capable of interacting with WT1. Some of these studies placed WT1, its downstream targets, and protein partners in a transcriptional regulatory network that controls urogenital system development. We review herein studies on WT1 knockout and transgenic models that have been instrumental in defining a physiological role for WT1 in normal and abnormal urogenital development.
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Srichai MB, Konieczkowski M, Padiyar A, Konieczkowski DJ, Mukherjee A, Hayden PS, Kamat S, El-Meanawy MA, Khan S, Mundel P, Lee SB, Bruggeman LA, Schelling JR, Sedor JR. A WT1 co-regulator controls podocyte phenotype by shuttling between adhesion structures and nucleus. J Biol Chem 2004; 279:14398-408. [PMID: 14736876 DOI: 10.1074/jbc.m314155200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glomerular podocyte differentiation state is critical for filtration barrier function and is regulated by WT1, a zinc finger transcription factor. A yeast two-hybrid assay identified a novel, WT1-interacting protein (WTIP) that maps to human chromosome 19q13.1, a region with genes linked to familial focal segmental glomerulosclerosis. The domain structure of WTIP is similar to the zyxin subfamily of cytosolic LIM domain-containing proteins, which contain three carboxyl-terminal LIM protein-protein interaction domains and a proline-rich, pre-LIM region with a nuclear export signal. Other LIM domain-containing proteins (zyxin and mouse muscle LIM protein) did not interact with WT1 in two-hybrid assays, and WTIP did not interact with an unrelated transcription factor, LMX1B. WTIP mRNA was detected in cultured podocytes and was developmentally regulated, with expression peaking in mouse kidney at embryonic day 15-16 (E15-E16) in kidney but persisting into adulthood. In situ hybridization demonstrated WTIP expression in developing E15 glomeruli and in cultured podocytes. The partial WTIP clone, which interacted with WTIP in the two-hybrid assay, co-localized with WT1 in nuclei, co-precipitated with WT1, and inhibited WT1-dependent transcriptional activation of the amphiregulin promoter. In contrast, full-length WTIP was excluded from cell nuclei, but after the addition of leptomycin B, an inhibitor of Crm1-mediated nuclear export, it accumulated in the nucleus and co-precipitated with WT1 in whole cell lysates. Epitope-tagged WTIP co-localized with the adaptor protein CD2AP (CMS) in podocyte actin spots and with Mena at cell-cell junctions. We propose that WTIP monitors slit diaphragm protein assembly as part of a multiple protein complex, linking this specialized adhesion junction to the actin cytoskeleton, and shuttles into the nucleus after podocyte injury, providing a mechanism whereby changes in slit diaphragm structure modulate gene expression.
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Affiliation(s)
- Manakan B Srichai
- Departments of Medicine and Physiology and Biophysics, School of Medicine, Case Western Reserve University and Rammelkamp Center for Research and Education, MetroHealth System Campus, Cleveland, Ohio 44109-1998, USA
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Knower KC, Kelly S, Harley VR. Turning on the male – SRY, SOX9 and sex determination in mammals. Cytogenet Genome Res 2003; 101:185-98. [PMID: 14684982 DOI: 10.1159/000074336] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Accepted: 07/02/2003] [Indexed: 11/19/2022] Open
Abstract
The decision of the bi-potential gonad to develop into either a testis or ovary is determined by the presence or absence of the Sex-determining Region gene on the Y chromosome (SRY). Since its discovery, almost 13 years ago, the molecular role that SRY plays in initiating the male sexual development cascade has proven difficult to ascertain. While biochemical studies of clinical mutants and mouse genetic models have helped in our understanding of SRY function, no direct downstream targets of SRY have yet been identified. There are, however, a number of other genes of equal importance in determining sexual phenotype, expressed before and after expression of SRY. Of these, one has proven of central importance to mammals and vertebrates, SOX9. This review describes our current knowledge of SRY and SOX9 structure and function in the light of recent key developments.
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Affiliation(s)
- K C Knower
- Human Molecular Genetics Laboratory, Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
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Matsuzawa-Watanabe Y, Inoue JI, Semba K. Transcriptional activity of testis-determining factor SRY is modulated by the Wilms' tumor 1 gene product, WT1. Oncogene 2003; 22:7900-4. [PMID: 12970737 DOI: 10.1038/sj.onc.1206717] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Wilms' tumor 1 (WT1) and sex-determining region of the Y chromosome (SRY) genes are essential for development of the mammalian gonads and mutations in these genes are associated with gonadal dysgenesis in humans. The SRY gene encodes a transcription factor with one high-mobility group (HMG) box as a DNA-binding domain. WT1 encodes a transcription factor that contains four contiguous C2H2-type zinc-finger motifs as a DNA/RNA binding or protein-protein interaction domain. Here we report that WT1 binds to and acts synergistically with SRY to activate transcription from a promoter containing SRY-binding sites. This interaction is mediated by the WT1 zinc-finger domain and the SRY HMG box. WT1 mutants associated with Denys-Drash syndrome (DDS), which is characterized by Wilms' tumor, pseudohermaphroditism, and nephropathy, fail to interact with SRY. Wildtype WT1 is recruited to SRY-binding sites in an SRY-dependent manner, whereas DDS mutants are not recruited as efficiently. These results suggest that WT1 forms a complex with SRY to regulate transcription and that this WT1-SRY interaction is important in testis development.
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Affiliation(s)
- Yumiko Matsuzawa-Watanabe
- Department of Cancer Biology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
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