DOCSLIB.ORG

Clinical Value of NPHS2 Analysis in Early- and Adult-Onset Steroid-Resistant Nephrotic Syndrome

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Clinical Value of NPHS2 Analysis in Early- and Adult-Onset Steroid-Resistant Nephrotic Syndrome Article Clinical Value of NPHS2 Analysis in Early- and Adult-Onset Steroid-Resistant Nephrotic Syndrome Sheila Santín,* Ba´rbara Tazo´n-Vega,* Irene Silva,* María A´ ngeles Cobo,† Isabel Gime´nez,‡ Patricia Ruíz,* Rafael García-Maset,‡ Jose´Ballarín,‡ Roser Torra,‡ and Elisabet Ars,* on behalf of the FSGS Spanish Study Group Summary Background and objectives To date, very few cases with adult-onset focal segmental glomerulosclerosis *Molecular Biology (FSGS) carrying NPHS2 variants have been described, all of them being compound heterozygous for the Laboratory, Fundacio´ p.R229Q variant and one pathogenic mutation. Puigvert, Universitat Auto`noma de Design, setting, participants, & measurements Mutation analysis was performed in 148 unrelated Spanish Barcelona, REDinREN, Instituto de patients, of whom 50 presented with FSGS after 18 years of age. Pathogenicity of amino acid substitutions Investigacio´n Carlos III, was evaluated through an in silico scoring system. Haplotype analysis was carried out using NPHS2 single Barcelona, Spain; nucleotide polymorphism and microsatellite markers. †Nephrology Department, Hospital Universitario de Results Compound heterozygous or homozygous NPHS2 pathogenic mutations were identified in seven Canarias, Tenerife, childhood-onset steroid-resistant nephrotic syndrome (SRNS) cases. Six additional cases with late child- Spain; and ‡Nephrology hood- and adult-onset SRNS were compound heterozygotes for p.R229Q and one pathogenic mutation, Department, Fundacio´ mostly p.A284V. p.R229Q was more frequent among SRNS cases relative to controls (odds ratio ϭ 2.65; Puigvert, Universitat ϭ Auto`noma de P 0.02). Significantly higher age at onset of the disease and slower progression to ESRD were found in Barcelona, REDinREN, patients with one pathogenic mutation plus the p.R229Q variant in respect to patients with two NPHS2 Instituto de pathogenic mutations. Investigacio´n Carlos III, Barcelona, Spain Conclusions NPHS2 analysis has a clinical value in both childhood- and adult-onset SRNS patients. For adult-onset patients, the first step should be screening for p.R229Q and, if positive, for p.A284V. These al- Correspondence: Dr. Roser Torra or Dr. leles are present in conserved haplotypes, suggesting a common origin for these substitutions. Patients car- Elisabet Ars, Fundacio´ rying this specific NPHS2 allele combination did not respond to corticoids or immunosuppressors and Puigvert, Cartagena 340- showed FSGS, average 8-year progression to ESRD, and low risk for recurrence of FSGS after kidney 350, 08025 Barcelona, ϩ transplant. Spain. Phone: 34 93 416 97 00; Fax: ϩ34 93 Clin J Am Soc Nephrol 6: 344–354, 2011. doi: 10.2215/CJN.03770410 416 97 30; E-mail: rtorra@fundacio- puigvert.es or ears@ Introduction onset familial cases of autosomal-recessive SRNS (5). fundacio-puigvert.es Nephrotic syndrome (NS) is characterized by edema, Nearly all patients with two NPHS2 pathogenic mu- massive proteinuria, hypoalbuminemia, and hyper- tations develop NS before the age of 6 years, present lipidemia. Clinically, NS has been divided into two mostly with FSGS, do not respond to immunosup- categories based on the response to steroid therapy: pressant treatment, reach ESRD before the end of the steroid-sensitive NS (SSNS) and steroid-resistant NS first decade of life, and have a reduced risk for recur- (SRNS) (1). In children and adults with SRNS, renal rence of FSGS after kidney transplant (8 versus 33%) histology typically shows focal segmental glomerulo- (13–19). In addition, Tsukaguchi et al. (20) reported sclerosis (FSGS), and 50 to 70% of patients progress to NPHS2 variants in 23% of late-onset familial cases and ESRD (2,3). In the last few years, mutations in genes in 2% of sporadic ones. In contrast, NPHS2 mutations encoding podocyte proteins have been identified in were not found in four large cohorts of adult-onset several forms of hereditary SRNS (4–10). cases published subsequently (21–24). Recently, Ma- To date, the main player in the genetic forms of chuca et al. (25) identified NPHS2 substitutions in 14% SRNS has been podocin, encoded by the NPHS2 gene of cases presenting with SRNS after 18 years of age. (11). Podocin is a 383-amino acid lipid-raft–associated Fifteen sporadic and 11 families with adult-onset protein localized at the slit diaphragm, where it is FSGS carrying NPHS2 variants have been reported required for the structural organization and regula- thus far, and affected individuals were compound tion of the glomerular filtration barrier. Its interaction heterozygous for a particular variant, p.R229Q, and with nephrin, NEPH1, CD2AP, and TRPC6 manage one pathogenic mutation, which was frequently the mechanosensation signaling, podocyte survival, cell p.A284V substitution among South American pa- polarity, and cytoskeletal organization (12). The tients. Although p.R229Q is one of the most common NPHS2 gene was identified 10 years ago in early- nonsynonymous NPHS2 variants in Caucasians (26), 344 Copyright © 2011 by the American Society of Nephrology www.cjasn.org Vol 6 February, 2011 Clin J Am Soc Nephrol 6: 344–354, February, 2011 NPHS2 in Childhood- and Adult-Onset SRNS, Santín et al. 345 its pathogenic role in SRNS is not clear because it is members. Unpublished missense mutations were observed with similar allele frequencies in SRNS and screened in 300 control chromosomes either by direct normal control subjects (5.13 and 3.75%, respectively) sequencing or by specific restriction enzyme diges- (17,18). Support for a functional role of this variant tion. comes from in vitro studies showing decreased neph- rin binding to mutant p.R229Q-podocin (20). Classification of Sequence Variants The goals of this study were (1) to assess the We developed an in silico scoring system to evalu- utility of NPHS2 testing in Spanish children and ate the pathogenicity of amino acid substitutions adults with SRNS or FSGS, (2) to determine (missense mutations) identified in the NPHS2 gene. whether the p.A284V pathogenic mutation and the This scoring system takes into consideration a num- p.R229Q variant occur on conserved haplotypes, (3) ber of in silico predictors (28–30) and population data. to evaluate genotype–phenotype correlation among We scored each of these factors, the sum of which patients with NPHS2 variants, focusing on adult resulted in an overall variant score (VS). These were Ն patients with FSGS, and (4) to study the association classified into four groups (30): VS 11 (highly likely ϭ Ն Յ with SRNS of the relatively common p.P20L, pathogenic, mutation group [MG] B); 10 VS 5 ϭ Ն Յ p.R229Q, and p.E264Q NPHS2 variants in a case- (likely pathogenic, MG C), 4 VS 0 (indetermi- ϭ Յ Ϫ control study. nate, MG I), and VS 1 (highly likely neutral, MG ϭ NV). Nonsense and frameshift mutations were classed as definitely pathogenic mutations (MG ϭ A) Materials and Methods because they are predicted to result in truncated pro- Patients teins. From a group of 239 Spanish patients with NS We considered “pathogenic mutations” to be those referred for NPHS2 mutation analysis, we selected sequence variants predicted to result in a truncated patients affected by SRNS (1,2) to evaluate NPHS2 protein (MG ϭ A) and those amino acid substitutions genotype–phenotype correlations. We excluded pa- not found in healthy controls, segregated with the tients with a potential underlying immune disorder disease in families, and expected to severely alter the defined by remission after steroid (n ϭ 37) or immu- ϭ ϭ protein sequence using in silico predictors (MG B). nosuppressive (n 18) therapy or late steroid resis- Missense substitutions classified as MG ϭ C or I were tance (n ϭ 7). Moreover, individuals with evidence of ϭ designated as “variants of unknown clinical signifi- autosomal-dominant disease (n 6), as well as those cance.” in whom we identified mutations in NPHS1, WT1, or ϭ TRPC6 (n 23), were excluded. Renal biopsy was Haplotype Analysis available in all patients with adult-onset NS and all We genotyped family members of patients carrying the showed FSGS. Secondary forms of FSGS were not p.R229Q variant and p.A284V mutation using NPHS2 mi- included. The cohort analyzed in this study thus rep- crosatellite markers (D1S3758, D1S3760, D1S215, D1S3759, resented 148 patients belonging to 139 families with and D1S2883). Haplotype construction was also carried SRNS. Patients originating from a consanguineous out using eight single nucleotide polymorphisms (SNPs): marriage (n ϭ 4) or those with an additional affected 5ЈUTR-52CϾG, 5ЈUTR-51GϾT(rs12406197), c.102GϾA sibling (n ϭ 8) were considered as familial cases. The (rs1079292), c.288CϾT(rs3738423), IVS3–21CϾT remaining 127 were sporadic SRNS cases. Age at on- (rs12401708), IVS7ϩ7AϾG, c.954TϾC(rs1410592), and set of NS, response to treatment, histopathologic find- c.1038AϾG(rs3818587). Moreover, three informative SNPs ings, progression to ESRD, and recurrence after kid- (5ЈUTR-51GϾT, IVS3–21CϾT, and c.954TϾC) were cho- ney transplantation were obtained (Table 1). We sen for further analysis in patients and controls carrying classified our population according to the age at onset the p.R229Q variant. of the disease in early childhood onset (0 to 5 years; 34.4 Ϯ 17.4 months, n ϭ 65), late childhood onset (6 to Statistical Analyses 17 years; 11.1 Ϯ 3.5 years, n ϭ 33), and adult onset Data are expressed as mean Ϯ SD. Comparisons (Ͼ18 years; 32.9 Ϯ 10.8 years, n ϭ 50). To calculate between two continuous variables were made using t mutation frequency, we used the number of families; tests. Genetic associations between NPHS2 variants when evaluating phenotype, we considered number and SRNS were assessed by comparing genotypic of patients. frequencies between patients and control subjects (matched by ethnicity and geography with the study cohort) using ␹2 or Fisher’s exact test. The odds ratio Mutation Analysis was calculated with 95% confidence interval. All tests Genomic DNA was isolated from peripheral blood were two-sided.
Load more

Recommended publications
  • Linkage Analysis of Candidate Loci for End-Stage Renal Disease Due to Diabetic Nephropathy
    J Am Soc Nephrol 14: S195–S201, 2003 Linkage Analysis of Candidate Loci for End-Stage Renal Disease due to Diabetic Nephropathy SUDHA K. IYENGAR,*† KATHERINE A. FOX,*† MARLENE SCHACHERE,*† FAUZIA MANZOOR,*† MARY E. SLAUGHTER,*† ADRIAN M. COVIC,†‡ S. MOHAMMED ORLOFF,*† PATRICK S. HAYDEN,†‡ JANE M. OLSON,*† JEFFREY R. SCHELLING,†‡ and JOHN R. SEDOR†‡ Departments of *Epidemiology and Biostatistics, and ‡Medicine, Case Western Reserve University, and †Rammelkamp Center for Research and Education, MetroHealth Medical Center, Cleveland, Ohio. Abstract. Diabetic nephropathy (DN), a major cause of ESRD, ate in the final linkage analysis. To date, we have collected 212 is undoubtedly multifactorial and is caused by environmental sib pairs from 46 CA and 50 AA families. The average age of and genetic factors. To identify a genetic basis for DN suscep- diabetes onset was 46.8 yr versus 36.2 yr for CA and 39.5 yr tibility, we are collecting multiplex DN families in the Cauca- versus 40.2 yr for AA, in males versus females respectively. sian (CA) and African-American (AA) populations for whole Genotyping data were available for 106 sib pairs (43 CA, 63 genome scanning and candidate gene analysis. A candidate AA) from 27 CA (44% male probands) and 38 AA families gene search of diabetic sibs discordantly affected, concordantly (43% male probands). Average AA and CA sibship size was affected and concordantly unaffected for DN was performed 2.73. Singlepoint and multipoint linkage analyses indicate that with microsatellite markers in genomic regions suspected to marker D10S1654 on chromosome 10p is potentially linked to harbor nephropathy susceptibility loci.
    [Show full text]
  • Expression Pattern of CD2AP in the Intact and Collaterally Sprouting Nervous System
    University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 8-2011 Expression pattern of CD2AP in the intact and collaterally sprouting nervous system. Sarah Elizabeth Claypool Couch 1987- University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Recommended Citation Couch, Sarah Elizabeth Claypool 1987-, "Expression pattern of CD2AP in the intact and collaterally sprouting nervous system." (2011). Electronic Theses and Dissertations. Paper 279. https://doi.org/10.18297/etd/279 This Master's Thesis is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. EXPRESSION PATTERN OF CD2AP IN THE INTACT AND COLLATERALL Y SPROUTING NERVOUS SYSTEM By Sarah Elizabeth Claypool Couch B.S., Centre College, 2009 A Thesis Submitted to the Faculty of the School of Medicine of the University of Louisville in Fulfillment of the Requirements for the Degree of Master of Science Department of Anatomical Sciences and Neurobiology University of Louisville Louisville, Kentucky August 2011 EXPRESSION PATTERN OF CD2AP IN THE INTACT AND COLLA TERALL Y SPROUTING NERVOUS SYSTEM By Sarah Elizabeth Claypool Couch B.S., Centre College, 2009 A Thesis Approved on July 19,2011 By the following Thesis Committee: Jeffrey Petruska, Ph.D. Theo Hagg, M.D., Ph.D.
    [Show full text]
  • Human Induced Pluripotent Stem Cell–Derived Podocytes Mature Into Vascularized Glomeruli Upon Experimental Transplantation
    BASIC RESEARCH www.jasn.org Human Induced Pluripotent Stem Cell–Derived Podocytes Mature into Vascularized Glomeruli upon Experimental Transplantation † Sazia Sharmin,* Atsuhiro Taguchi,* Yusuke Kaku,* Yasuhiro Yoshimura,* Tomoko Ohmori,* ‡ † ‡ Tetsushi Sakuma, Masashi Mukoyama, Takashi Yamamoto, Hidetake Kurihara,§ and | Ryuichi Nishinakamura* *Department of Kidney Development, Institute of Molecular Embryology and Genetics, and †Department of Nephrology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; ‡Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima, Japan; §Division of Anatomy, Juntendo University School of Medicine, Tokyo, Japan; and |Japan Science and Technology Agency, CREST, Kumamoto, Japan ABSTRACT Glomerular podocytes express proteins, such as nephrin, that constitute the slit diaphragm, thereby contributing to the filtration process in the kidney. Glomerular development has been analyzed mainly in mice, whereas analysis of human kidney development has been minimal because of limited access to embryonic kidneys. We previously reported the induction of three-dimensional primordial glomeruli from human induced pluripotent stem (iPS) cells. Here, using transcription activator–like effector nuclease-mediated homologous recombination, we generated human iPS cell lines that express green fluorescent protein (GFP) in the NPHS1 locus, which encodes nephrin, and we show that GFP expression facilitated accurate visualization of nephrin-positive podocyte formation in
    [Show full text]
  • NPHS2 (Podocin) Mutations in Nephrotic Syndrome
    0031-3998/05/5705-0054R PEDIATRIC RESEARCH Vol. 57, No. 5, Pt 2, 2005 Copyright © 2005 International Pediatric Research Foundation, Inc. Printed in U.S.A. NPHS2 (Podocin) Mutations in Nephrotic Syndrome. Clinical Spectrum and Fine Mechanisms GIANLUCA CARIDI, FRANCESCO PERFUMO, AND GIAN MARCO GHIGGERI Laboratory on Pathophysiology of Uremia [G.C., G.M.C.], and Renal Unit [F.P., G.M.C.], Istituto Giannina Gaslini, 16148 Genova, Italy. ABSTRACT Nephrotic syndrome (NS) is the most frequent cause of iments with the common R229Q polymorphism demonstrated an proteinuria in children and is emerging as a leading cause of altered interaction with nephrin that affects the stability of the uremia. Molecular studies in families with recessive NS have led functional unit. Overall, data are here presented that underscore to the discovery of specialized molecules endowed in podocytes a major role of inherited defects of NPHS2 in NS in children that play a role in proteinuria. This review focalizes the key (including a relevant impact in sporadic cases) and give the position of podocin (NPHS2 gene) in this rapidly evolving field functional rationale for the association. A practical compendium and furnishes a compendium to those involved in clinics and is also given to clinicians involved in the management of NS that genetics of NS. Screening for NPHS2 mutations have been done should modify the classic therapeutic approach. (Pediatr Res 57: in sporadic NS and familial cases with recessive inheritance, 54R–61R, 2005) documenting a mutation detection rate of 45–55% in families and 8–20% in sporadic NS according to the different groups and considering all the clinical phenotypes.
    [Show full text]
  • A Novel PLEKHA7 Interactor at Adherens Junctions
    Thesis PDZD11: a novel PLEKHA7 interactor at adherens junctions GUERRERA, Diego Abstract PLEKHA7 is a recently identified protein of the AJ that has been involved by genetic and genomic studies in the regulation of miRNA signaling and cardiac contractility, hypertension and glaucoma. However, the molecular mechanisms behind PLEKHA7 involvement in tissue physiology and pathology remain unknown. In my thesis I report novel results which uncover PLEKHA7 functions in epithelial and endothelial cells, through the identification of a novel molecular interactor of PLEKHA7, PDZD11, by yeast two-hybrid screening, mass spectrometry, co-immunoprecipitation and pulldown assays. I dissected the structural basis of their interaction, showing that the WW domain of PLEKHA7 binds to the N-terminal region of PDZD11; this interaction mediates the junctional recruitment of PDZD11, identifying PDZD11 as a novel AJ protein. I provided evidence that PDZD11 forms a complex with nectins at AJ, its PDZ domain binds to the PDZ-binding motif of nectins. PDZD11 stabilizes nectins promoting the early steps of junction assembly. Reference GUERRERA, Diego. PDZD11: a novel PLEKHA7 interactor at adherens junctions. Thèse de doctorat : Univ. Genève, 2016, no. Sc. 4962 URN : urn:nbn:ch:unige-877543 DOI : 10.13097/archive-ouverte/unige:87754 Available at: http://archive-ouverte.unige.ch/unige:87754 Disclaimer: layout of this document may differ from the published version. 1 / 1 UNIVERSITE DE GENÈVE FACULTE DES SCIENCES Section de Biologie Prof. Sandra Citi Département de Biologie Cellulaire PDZD11: a novel PLEKHA7 interactor at adherens junctions THÈSE Présentée à la Faculté des sciences de l’Université de Genève Pour obtenir le grade de Doctor ès science, mention Biologie par DIEGO GUERRERA de Benevento (Italie) Thèse N° 4962 GENÈVE Atelier d'impression Repromail 2016 1 Table of contents RÉSUMÉ ..................................................................................................................
    [Show full text]
  • The Adaptor Protein CD2AP Is a Coordinator of Neurotrophin Signaling-Mediated Axon Arbor Plasticity
    The Journal of Neuroscience, April 13, 2016 • 36(15):4259–4275 • 4259 Cellular/Molecular The Adaptor Protein CD2AP Is a Coordinator of Neurotrophin Signaling-Mediated Axon Arbor Plasticity Benjamin J. Harrison,1,2,3 Gayathri Venkat,1,2 James L. Lamb,4 Tom H. Hutson,5 XCassa Drury,6 Kristofer K. Rau,7 Mary Barlett Bunge,8,9 Lorne M. Mendell,9,10 XFred H. Gage,9,11 Richard D. Johnson,12,13 Caitlin E. Hill,14,15 Eric C. Rouchka,3,16 XLawrence D.F. Moon,5 and XJeffrey C. Petruska1,2,17 1Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky 40202, 2Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky 40292, 3Kentucky Biomedical Research Infrastructure Network, University of Louisville, Louisville, Kentucky 40292, 4University of Louisville School of Medicine, Louisville, Kentucky 40292, 5Wolfson Centre for Age Related Diseases, King’s College, London SE1 1UL, United Kingdom, 6DuPont Manual High School, Louisville, Kentucky 40205, 7Anesthesiology and Perioperative Medicine, University of Louisville, Louisville, Kentucky 40202, 8Miami Project to Cure Paralysis, Department of Neurological Surgery and Neurology, University of Miami Miller School of Medicine, Miami, Florida 33136, 9Christopher and Dana Reeve Foundation International Consortium on Spinal Cord Injury Research, Short Hills, New Jersey 07078, 10Department of Neurobiology and Behavior, State University of New York at Stony Brook, Stony Brook, New York 11794, 11Laboratory of Genetics, The Salk Institute, La Jolla, California
    [Show full text]
  • Mouse Cd2ap Conditional Knockout Project (CRISPR/Cas9)
    https://www.alphaknockout.com Mouse Cd2ap Conditional Knockout Project (CRISPR/Cas9) Objective: To create a Cd2ap conditional knockout Mouse model (C57BL/6J) by CRISPR/Cas-mediated genome engineering. Strategy summary: The Cd2ap gene (NCBI Reference Sequence: NM_009847 ; Ensembl: ENSMUSG00000061665 ) is located on Mouse chromosome 17. 18 exons are identified, with the ATG start codon in exon 1 and the TGA stop codon in exon 18 (Transcript: ENSMUST00000024709). Exon 4 will be selected as conditional knockout region (cKO region). Deletion of this region should result in the loss of function of the Mouse Cd2ap gene. To engineer the targeting vector, homologous arms and cKO region will be generated by PCR using BAC clone RP24-340J5 as template. Cas9, gRNA and targeting vector will be co-injected into fertilized eggs for cKO Mouse production. The pups will be genotyped by PCR followed by sequencing analysis. Note: Homozygotes for a targeted null mutation exhibit impaired immune function and die at 6 to 7 weeks of age from kidney failure associated with podocyte defects and mesangial cell hyperplasia. Heterozygotes develop glomerular changes around 9 months. Exon 4 starts from about 16.75% of the coding region. The knockout of Exon 4 will result in frameshift of the gene. The size of intron 3 for 5'-loxP site insertion: 6523 bp, and the size of intron 4 for 3'-loxP site insertion: 4416 bp. The size of effective cKO region: ~601 bp. The cKO region does not have any other known gene. Page 1 of 7 https://www.alphaknockout.com Overview of the Targeting Strategy Wildtype allele gRNA region 5' gRNA region 3' 1 4 18 Targeting vector Targeted allele Constitutive KO allele (After Cre recombination) Legends Exon of mouse Cd2ap Homology arm cKO region loxP site Page 2 of 7 https://www.alphaknockout.com Overview of the Dot Plot Window size: 10 bp Forward Reverse Complement Sequence 12 Note: The sequence of homologous arms and cKO region is aligned with itself to determine if there are tandem repeats.
    [Show full text]
  • Nuclear Relocation of the Nephrin and CD2AP-Binding Protein Dendrin Promotes Apoptosis of Podocytes
    Nuclear relocation of the nephrin and CD2AP-binding protein dendrin promotes apoptosis of podocytes Katsuhiko Asanuma*, Kirk Nicholas Campbell, Kwanghee Kim, Christian Faul, and Peter Mundel† Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029 Edited by Marilyn Gist Farquhar, University of California at San Diego School of Medicine, La Jolla, CA, and approved April 28, 2007 (received for review February 1, 2007) Kidney podocytes and their slit diaphragms (SDs) form the final Results barrier to urinary protein loss. There is mounting evidence that SD Dendrin Is a Component of the SD Complex. Dendrin contains two proteins also participate in intracellular signaling pathways. The SD putative nuclear localization signals (NLSs) and three PPXY protein nephrin serves as a component of a signaling complex that motifs that are preserved among human, rat, and mouse (Fig. directly links podocyte junctional integrity to actin cytoskeletal 1a). To explore the renal expression of dendrin, we generated dynamics. Another SD protein, CD2-associated protein (CD2AP), is and affinity-purified a peptide antibody against the C terminus an adaptor molecule involved in podocyte homeostasis that can of mouse dendrin. This antibody detected the previously de- repress proapoptotic TGF-␤ signaling in podocytes. Here we show scribed 89-kDa and 81-kDa isoforms of dendrin in the brain but that dendrin, a protein originally identified in telencephalic den- only the 81-kDa isoform in isolated glomeruli (Fig. 1b). By drites, is a constituent of the SD complex, where it directly binds immunofluorescence microscopy of adult mouse kidney, dendrin to nephrin and CD2AP. In experimental glomerulonephritis, den- was detected exclusively in glomeruli (Fig.
    [Show full text]
  • CD2AP and Cbl-3/Cbl-C Constitute a Critical Checkpoint in the Regulation of Ret Signal Transduction
    The Journal of Neuroscience, August 27, 2008 • 28(35):8789–8800 • 8789 Development/Plasticity/Repair CD2AP and Cbl-3/Cbl-c Constitute a Critical Checkpoint in the Regulation of Ret Signal Transduction Cynthia C. Tsui1,3 and Brian A. Pierchala2,3 1Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109-0680, 2Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, Michigan 48109-1078, and 3Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, New York 14260 The glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs) are critical for nervous system development and mainte- nance. GFLs promote survival and growth via activation of the receptor tyrosine kinase (RTK) Ret. In sympathetic neurons, the duration of Ret signaling is governed by how rapidly Ret is degraded after its activation. In an effort to elucidate mechanisms that control the half-life of Ret, we have identified two novel Ret interactors, CD2-associated protein (CD2AP) and Cbl-3. CD2AP, an adaptor molecule involved in the internalization of ubiquitinated RTKs, is associated with Ret under basal, unstimulated conditions in neurons. After Ret activation by GDNF, CD2AP dissociates. Similarly, the E3-ligase Cbl-3 interacts with unphosphorylated Ret and dissociates from Ret after Ret activation. In contrast to their dissociation from autophosphorylated Ret, an interaction between CD2AP and Cbl-3 is induced by GDNF stimulation of sympathetic neurons, suggesting that CD2AP and Cbl-3 dissociate from Ret as a complex. In neurons, the overex- pression of CD2AP enhances the degradation of Ret and inhibits GDNF-dependent survival, and gene silencing of CD2AP blocks Ret degradation and promotes GDNF-mediated survival.
    [Show full text]
  • Transcriptional Induction of Slit Diaphragm Genes by Lmx1b Is Required in Podocyte Differentiation
    Transcriptional induction of slit diaphragm genes by Lmx1b is required in podocyte differentiation Jeffrey H. Miner, … , Andrey S. Shaw, Brendan Lee J Clin Invest. 2002;109(8):1065-1072. https://doi.org/10.1172/JCI13954. Article Genetics LMX1B encodes a LIM-homeodomain transcription factor. Mutations inL MX1B cause nail-patella syndrome (NPS), an autosomal dominant disease with skeletal abnormalities, nail hypoplasia, and nephropathy. Expression of glomerular basement membrane (GBM) collagens is reduced in Lmx1b–/– mice, suggesting one basis for NPS nephropathy. Here, we show that Lmx1b–/– podocytes have reduced numbers of foot processes, are dysplastic, and lack typical slit diaphragms, indicating an arrest in development. Using antibodies to podocyte proteins important for podocyte function, we found that Lmx1b–/– podocytes express near-normal levels of nephrin, synaptopodin, ZO-1, α3 integrin, and GBM laminins. However, mRNA and protein levels for CD2AP and podocin were greatly reduced, suggesting a cooperative role for these molecules in foot process and slit diaphragm formation. We identified several LMX1B binding sites in the putative regulatory regions of both CD2AP and NPHS2 (podocin) and demonstrated that LMX1B binds to these sequences in vitro and can activate transcription through them in cotransfection assays. Thus, LMX1B regulates the expression of multiple podocyte genes critical for podocyte differentiation and function. Our results indicate that reduced levels of proteins associated with foot processes and the glomerular slit diaphragm likely contribute, along with reduced levels of GBM collagens, to the nephropathy associated with NPS. Find the latest version: https://jci.me/13954/pdf Transcriptional induction of slit diaphragm genes by Lmx1b is required in podocyte differentiation Jeffrey H.
    [Show full text]
  • CD2AP Regulates Sumoylation of CIN85 in Podocytes
    Dartmouth College Dartmouth Digital Commons Dartmouth Scholarship Faculty Work 12-27-2011 CD2AP Regulates SUMOylation of CIN85 in Podocytes Irini Tossidou Harvard University Rainer Niedenthal Hannover Medical School Malte Klaus Hannover Medical School Beina Teng Harvard University Kirstin Worthmann Harvard University See next page for additional authors Follow this and additional works at: https://digitalcommons.dartmouth.edu/facoa Part of the Medical Cell Biology Commons, and the Medical Molecular Biology Commons Dartmouth Digital Commons Citation Tossidou, Irini; Niedenthal, Rainer; Klaus, Malte; Teng, Beina; Worthmann, Kirstin; King, Benjamin; and Peterson, Kevin, "CD2AP Regulates SUMOylation of CIN85 in Podocytes" (2011). Dartmouth Scholarship. 1226. https://digitalcommons.dartmouth.edu/facoa/1226 This Article is brought to you for free and open access by the Faculty Work at Dartmouth Digital Commons. It has been accepted for inclusion in Dartmouth Scholarship by an authorized administrator of Dartmouth Digital Commons. For more information, please contact [email protected]. Authors Irini Tossidou, Rainer Niedenthal, Malte Klaus, Beina Teng, Kirstin Worthmann, Benjamin King, and Kevin Peterson This article is available at Dartmouth Digital Commons: https://digitalcommons.dartmouth.edu/facoa/1226 CD2AP Regulates SUMOylation of CIN85 in Podocytes Irini Tossidou,a Rainer Niedenthal,b Malte Klaus,b Beina Teng,a Kirstin Worthmann,a Benjamin L. King,c Kevin J. Peterson,d Hermann Haller,a,c and Mario Schiffera,c Hannover Medical School, Department of Nephrology, Hannover, Germanya; Hannover Medical School, Institute of Physiological Chemistry/Biochemistry, Hannover, Germanyb; Mount Desert Island Biological Laboratory, Salisbury Cove, Maine, USAc; and Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, USAd Podocytes are highly differentiated and polarized epithelial cells located on the visceral side of the glomerulus.
    [Show full text]
  • Autocrine IFN Signaling Inducing Profibrotic Fibroblast Responses By
    Downloaded from http://www.jimmunol.org/ by guest on September 23, 2021 Inducing is online at: average * The Journal of Immunology , 11 of which you can access for free at: 2013; 191:2956-2966; Prepublished online 16 from submission to initial decision 4 weeks from acceptance to publication August 2013; doi: 10.4049/jimmunol.1300376 http://www.jimmunol.org/content/191/6/2956 A Synthetic TLR3 Ligand Mitigates Profibrotic Fibroblast Responses by Autocrine IFN Signaling Feng Fang, Kohtaro Ooka, Xiaoyong Sun, Ruchi Shah, Swati Bhattacharyya, Jun Wei and John Varga J Immunol cites 49 articles Submit online. Every submission reviewed by practicing scientists ? is published twice each month by Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts http://jimmunol.org/subscription Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html http://www.jimmunol.org/content/suppl/2013/08/20/jimmunol.130037 6.DC1 This article http://www.jimmunol.org/content/191/6/2956.full#ref-list-1 Information about subscribing to The JI No Triage! Fast Publication! Rapid Reviews! 30 days* Why • • • Material References Permissions Email Alerts Subscription Supplementary The Journal of Immunology The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2013 by The American Association of Immunologists, Inc. All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. This information is current as of September 23, 2021. The Journal of Immunology A Synthetic TLR3 Ligand Mitigates Profibrotic Fibroblast Responses by Inducing Autocrine IFN Signaling Feng Fang,* Kohtaro Ooka,* Xiaoyong Sun,† Ruchi Shah,* Swati Bhattacharyya,* Jun Wei,* and John Varga* Activation of TLR3 by exogenous microbial ligands or endogenous injury-associated ligands leads to production of type I IFN.
    [Show full text]