Tissue Expression of Nephrin in Human and Pig

Total Page:16

File Type:pdf, Size:1020Kb

Tissue Expression of Nephrin in Human and Pig 0031-3998/04/5505-0774 PEDIATRIC RESEARCH Vol. 55, No. 5, 2004 Copyright © 2004 International Pediatric Research Foundation, Inc. Printed in U.S.A. Tissue Expression of Nephrin in Human and Pig ARVI-MATTI KUUSNIEMI, MARJO KESTILÄ, JAAKKO PATRAKKA, ANNE-TIINA LAHDENKARI, VESA RUOTSALAINEN, CHRISTER HOLMBERG, RIITTA KARIKOSKI, RIITTA SALONEN, KARL TRYGGVASON, AND HANNU JALANKO Hospital for Children and Adolescents and Biomedicum Helsinki [A.-M.K., J.P., A.-T.L., C.H., R.K., H.J.], University of Helsinki, 00290 Helsinki, Finland; Department of Molecular Medicine [M.K.], National Public Health Institute, 00290 Helsinki, Finland; Biocenter and Department of Biochemistry [V.R.], University of Oulu, 90571 Oulu, Finland; Department of Obstetrics and Gynecology [R.S.], University of Helsinki, 00290 Helsinki, Finland; and Division of Matrix Biology [J.P., K.T.], Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden ABSTRACT Nephrin is a major component of the glomerular filtration cine fetuses, newborns, and infants. Likewise, nephrin mRNA barrier. Mutations in the nephrin gene (NPHS1) are responsible expression was not observed outside kidney glomerulus in nor- for congenital nephrotic syndrome of the Finnish type (NPHS1). mal or NPHS1 children. The phenotype analysis of NPHS1 Nephrin was at first thought to be podocyte specific, but recent children with severe nephrin gene mutations supported the find- studies have suggested that nephrin is also expressed in nonrenal ings in the tissue expression studies and revealed no impairment tissues such as pancreas and CNS. We studied the expression of of the neurologic, testicular, or pancreatic function in a great nephrin in human and porcine tissues at different stages of majority of the patients. The studies suggest that nephrin has no development and correlated these findings to clinical character- major clinical significance outside the kidney. (Pediatr Res 55: istics of NPHS1 children. Immunofluorescence staining and 774–781, 2004) Western blotting were used to detect nephrin protein in frozen tissue samples. Polyclonal antibodies against the intracellular Abbreviations part of nephrin were used in these analyses. In situ hybridization NPHS1, congenital nephrotic syndrome of the Finnish type was used to detect nephrin mRNA in specimens from normal IF, immunofluorescence human subjects and patients with NPHS1. Nephrin protein was RT-PCR, reverse transcriptase–PCR not detected in nonrenal tissues obtained from human and por- EST, expressed sequence tag Nephrin is a cell adhesion protein produced in kidney by the 26 kb. Mutations in NPHS1 lead to congenital nephrotic syn- glomerular epithelial cells (1). It is located at the podocyte slit drome of the Finnish type (NPHS1), which is an autosomal diaphragm, which is a crucial component of the glomerular recessive disorder characterized by nephrotic syndrome soon filtration barrier (2–4). Nephrin has 1241 amino acid residues after birth (15). The disease is highly enriched in the Finnish and belongs to the immunoglobulin superfamily containing population, but cases of NPHS1 are found all over the world eight immunoglobulin-like domains and one fibronectin-type (16–18). The Finnish patients have two important mutations domain in the extracellular part. The intracellular part has no (Fin-major and Fin-minor), which both lead to a truncated homology with other known proteins. It contains tyrosine protein and total absence of nephrin in kidney glomerulus (19). residues, and nephrin was recently shown to take part in cell In electron microscopy, these kidneys also lack the filamentous signaling together with two other podocyte proteins, podocin image of slit diaphragm, supporting the central role of nephrin and CD2-associated protein (5–10). The extracellular part of in the architecture of the slit diaphragm (19). nephrin interacts with Neph1, and the two proteins probably The expression of nephrin was at first thought to be limited form the backbone of the podocyte slit diaphragm (11–13). to kidney (1). However, in rodents, activity of nephrin gene Nephrin is encoded by NPHS1 gene located on chromosome promoter was observed in some parts of the CNS, such as the 19q13.1 (14). This gene consists of 29 exons and has a size of ventricular zone of the fourth ventricle; the developing spinal cord, cerebellum, hippocampus, and olfactory bulb; and ␤ cells of the pancreas (20, 21). In addition, the expression of nephrin Received May 12, 2003; accepted November 11, 2003. Correspondence: Hannu Jalanko, M.D., Hospital for Children and Adolescents, Uni- in murine testis, spleen, and thymus has been suggested (22). versity of Helsinki, 00290 Helsinki, Finland; e-mail: hannu.jalanko@hus.fi In humans, nephrin has been located in pancreatic ␤ cells but DOI: 10.1203/01.PDR.0000117842.10241.2C not in the CNS (23). We studied the expression of nephrin in 774 TISSUE EXPRESSION OF NEPHRIN 775 human and porcine tissues using immunohistochemical, in situ Laemmli sample buffer, and the proteins were separated on a hybridization, and Western blotting techniques and analyzed gel (7%) and blotted onto an Immobilon-P polyvinylidene the clinical data of patients with NPHS1. fluoride membrane (Millipore, Bedford, MA, U.S.A.). After blocking with 5% nonfat dry milk in PBS, the membrane was METHODS stained with rabbit anti-nephrin antibodies followed by perox- idase-conjugated goat anti-rabbit IgG antibodies (Jackson Im- Tissue samples. Human fetal samples were collected at munoResearch). Bound antibodies were visualized using en- autopsy from fetuses at 14, 18, and 20 wk of gestation obtained hanced chemiluminescence (Amersham Biosciences, Uppsala, through prostaglandin-induced abortions as a result of trisomy Sweden). The same antibody preparation was used for Western 21 (Department of Obstetrics and Gynecology, University of blotting and IF. Helsinki). In this disorder, abnormalities have not been de- In situ Hybridization. Formalin-fixed, paraffin-embedded tected in chromosome 19, where the gene for nephrin is sections (10 ␮m) were deparaffinized in xylene, rehydrated in located. Tissue samples were also obtained at autopsies of a decreasing alcohol series, and treated with proteinase-K newborn (died in sepsis) and five infants. Two human testis (Sigma Chemical Co., St. Louis, MO, U.S.A.) before hybrid- samples came from orchiectomies of adult men (supplied by ization. Thereafter, the sections were subjected to in situ Dr. Leo Dunkel) and one testis sample from a preterm baby (24 hybridization as described previously (25), with some modifi- wk of gestation) who died of lung problems at the age of 2 wk. Two of the infants had NPHS1 (Fin-major/Fin-minor geno- cations. Briefly, the tissue sections were washed in PBS, acetylated and dehydrated, and then incubated with 1.2 ϫ 106 types) and had died after renal transplantation at the ages of 2 33 and 3 y. Three infants died of congenital heart failure at the P-labeled (1000 Ci/mmol; Amersham, Arlington Heights, IL, ages of 4 mo, 6 mo, and 3 y. Porcine fetal samples were U.S.A.) antisense and sense riboprobes in a total volume of 80 ␮ obtained from aborted pregnancies at days 55 and 80 of Lat60°C for 18 h. After washes with standard saline culture, gestation (the total length of gestation is 114 d). In addition, RNA digestion, and dehydration, the sections were dipped in samples from newborn and a 6-mo-old pigs were used. NTB2 nuclear emulsion (Kodak, Rochester, NY, U.S.A.) and The use of the tissue samples and the study protocol were exposed in the dark at 4°C for 1 or 2 wk. After developing, the approved by the ethical committees of the Department of sections were counterstained with hematoxylin and eosin. Mi- Obstetrics and Gynecology and the Hospital for Children and croscopy was carried out with a standard Leica DM RX light Adolescents of the University of Helsinki. All human studies microscope. were conducted with informed consent. The probes for in situ studies were synthesized by subclon- Immunofluorescence staining. Rabbit polyclonal antiserum ing a 287-bp cDNA fragment corresponding to exon 10 in directed against the intracellular part of nephrin molecule was human NPHS1 into pBluescript (Stratagene, La Jolla, CA, used for the immunohistochemistry of nephrin. This antiserum U.S.A.), and antisense and sense RNA were produced using T3 was prepared as described previously (24). It was completely and T7 RNA polymerase, respectively. specific for nephrin and did not give any immunofluorescence Clinical data on NPHS1 children. Totally 56 children with (IF) staining for nonglomerular structures even in low dilu- NPHS1 have received kidney transplants since 1987 in Fin- tions. One polyclonal antiserum and three MAb preparations land. The clinical records of these children were analyzed against the extracellular domains of nephrin (3, 24) were also retrospectively, and the data regarding the neurologic find- tested but not used in the IF. These gave a slight background ings and pancreatic function were recorded. For studying the staining on nonglomerular epithelial structures, suggesting function of pancreatic ␤ cells, an oral glucose tolerance test cross-reactivity with epitopes in other proteins. Polyclonal was performed on 36 NPHS1 patients and 25 other kidney guinea pig anti-insulin antiserum (A0564; Dako Corporation, transplant patients 1 to 5 y after renal transplantation. The Carpinteria, CA, U.S.A.) was used as a positive control in test was done according to standard protocols, and blood immunohistochemistry of human and porcine pancreas. glucose and serum insulin levels were recorded for2hat For the IF stainings, cryosections (5 ␮m) of the tissue 30-min intervals. samples were fixed with 3.5% paraformaldehyde and incubated For elucidating the testicular function, serum sex hormone overnight at 4°C with antibodies diluted in PBS. FITC- conjugated secondary antibodies (Jackson ImmunoResearch levels were measured from eight 15- to 17-y-old boys who had Laboratories, West Grove, PA, U.S.A.) were incubated for 1 h. NPHS1 and had received a kidney transplant in infancy.
Recommended publications
  • Supplementary Table 1: Adhesion Genes Data Set
    Supplementary Table 1: Adhesion genes data set PROBE Entrez Gene ID Celera Gene ID Gene_Symbol Gene_Name 160832 1 hCG201364.3 A1BG alpha-1-B glycoprotein 223658 1 hCG201364.3 A1BG alpha-1-B glycoprotein 212988 102 hCG40040.3 ADAM10 ADAM metallopeptidase domain 10 133411 4185 hCG28232.2 ADAM11 ADAM metallopeptidase domain 11 110695 8038 hCG40937.4 ADAM12 ADAM metallopeptidase domain 12 (meltrin alpha) 195222 8038 hCG40937.4 ADAM12 ADAM metallopeptidase domain 12 (meltrin alpha) 165344 8751 hCG20021.3 ADAM15 ADAM metallopeptidase domain 15 (metargidin) 189065 6868 null ADAM17 ADAM metallopeptidase domain 17 (tumor necrosis factor, alpha, converting enzyme) 108119 8728 hCG15398.4 ADAM19 ADAM metallopeptidase domain 19 (meltrin beta) 117763 8748 hCG20675.3 ADAM20 ADAM metallopeptidase domain 20 126448 8747 hCG1785634.2 ADAM21 ADAM metallopeptidase domain 21 208981 8747 hCG1785634.2|hCG2042897 ADAM21 ADAM metallopeptidase domain 21 180903 53616 hCG17212.4 ADAM22 ADAM metallopeptidase domain 22 177272 8745 hCG1811623.1 ADAM23 ADAM metallopeptidase domain 23 102384 10863 hCG1818505.1 ADAM28 ADAM metallopeptidase domain 28 119968 11086 hCG1786734.2 ADAM29 ADAM metallopeptidase domain 29 205542 11085 hCG1997196.1 ADAM30 ADAM metallopeptidase domain 30 148417 80332 hCG39255.4 ADAM33 ADAM metallopeptidase domain 33 140492 8756 hCG1789002.2 ADAM7 ADAM metallopeptidase domain 7 122603 101 hCG1816947.1 ADAM8 ADAM metallopeptidase domain 8 183965 8754 hCG1996391 ADAM9 ADAM metallopeptidase domain 9 (meltrin gamma) 129974 27299 hCG15447.3 ADAMDEC1 ADAM-like,
    [Show full text]
  • Investigation of the Underlying Hub Genes and Molexular Pathogensis in Gastric Cancer by Integrated Bioinformatic Analyses
    bioRxiv preprint doi: https://doi.org/10.1101/2020.12.20.423656; this version posted December 22, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Investigation of the underlying hub genes and molexular pathogensis in gastric cancer by integrated bioinformatic analyses Basavaraj Vastrad1, Chanabasayya Vastrad*2 1. Department of Biochemistry, Basaveshwar College of Pharmacy, Gadag, Karnataka 582103, India. 2. Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad 580001, Karanataka, India. * Chanabasayya Vastrad [email protected] Ph: +919480073398 Chanabasava Nilaya, Bharthinagar, Dharwad 580001 , Karanataka, India bioRxiv preprint doi: https://doi.org/10.1101/2020.12.20.423656; this version posted December 22, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Abstract The high mortality rate of gastric cancer (GC) is in part due to the absence of initial disclosure of its biomarkers. The recognition of important genes associated in GC is therefore recommended to advance clinical prognosis, diagnosis and and treatment outcomes. The current investigation used the microarray dataset GSE113255 RNA seq data from the Gene Expression Omnibus database to diagnose differentially expressed genes (DEGs). Pathway and gene ontology enrichment analyses were performed, and a proteinprotein interaction network, modules, target genes - miRNA regulatory network and target genes - TF regulatory network were constructed and analyzed. Finally, validation of hub genes was performed. The 1008 DEGs identified consisted of 505 up regulated genes and 503 down regulated genes.
    [Show full text]
  • Identification of Novel Kirrel3 Gene Splice Variants in Adult Human
    Durcan et al. BMC Physiology 2014, 14:11 http://www.biomedcentral.com/1472-6793/14/11 RESEARCH ARTICLE Open Access Identification of novel Kirrel3 gene splice variants in adult human skeletal muscle Peter Joseph Durcan1, Johannes D Conradie1, Mari Van deVyver2 and Kathryn Helen Myburgh1* Abstract Background: Multiple cell types including trophoblasts, osteoclasts and myoblasts require somatic cell fusion events as part of their physiological functions. In Drosophila Melanogaster the paralogus type 1 transmembrane receptors and members of the immunoglobulin superfamily Kin of Irre (Kirre) and roughest (Rst) regulate myoblast fusion during embryonic development. Present within the human genome are three homologs to Kirre termed Kin of Irre like (Kirrel) 1, 2 and 3. Currently it is unknown if Kirrel3 is expressed in adult human skeletal muscle. Results: We investigated (using PCR and Western blot) Kirrel3 in adult human skeletal muscle samples taken at rest and after mild exercise induced muscle damage. Kirrel3 mRNA expression was verified by sequencing and protein presence via blotting with 2 different anti-Kirrel3 protein antibodies. Evidence for three alternatively spliced Kirrel3 mRNA transcripts in adult human skeletal muscle was obtained. Kirrel3 mRNA in adult human skeletal muscle was detected at low or moderate levels, or not at all. This sporadic expression suggests that Kirrel3 is expressed in a pulsatile manner. Several anti Kirrel3 immunoreactive proteins were detected in all adult human skeletal muscle samples analysed and results suggest the presence of different isoforms or posttranslational modification, or both. Conclusion: The results presented here demonstrate for the first time that there are at least 3 splice variants of Kirrel3 expressed in adult human skeletal muscle, two of which have never previously been identified in human muscle.
    [Show full text]
  • Nephrin Mutations Can Cause Childhood-Onset Steroid-Resistant Nephrotic Syndrome
    BRIEF COMMUNICATION www.jasn.org Nephrin Mutations Can Cause Childhood-Onset Steroid-Resistant Nephrotic Syndrome Aure´lie Philippe,*† Fabien Nevo,*† Ernie L. Esquivel,*† Dalia Reklaityte,*† ʈ Olivier Gribouval,*† Marie-Jose`phe Teˆte,*‡ Chantal Loirat,§ Jacques Dantal, Michel Fischbach,¶ Claire Pouteil-Noble,** Ste´phane Decramer,†† Martin Hoehne,‡‡ Thomas Benzing,‡‡ Marina Charbit,‡ Patrick Niaudet,*†‡ and Corinne Antignac*†§§ † *Inserm U574, Hoˆpital Necker-Enfants Malades, Universite´ Paris Descartes, Faculte´deMe´ decine Rene´ Descartes, BRIEF COMMUNICATION ‡Pediatric Nephrology and §§Department of Genetics, Hoˆpital Necker-Enfants Malades, Assistance Publique-Hoˆpitaux de Paris, and §Pediatric Nephrology Department, Universite´ Paris VII, Assistance Publique-Hoˆpitaux de Paris, Hoˆpital ʈ Robert Debre´, Paris, ITERT, Department of Nephrology and Clinical Immunology, CHU Nantes, Nantes, ¶Nephrology Dialysis Transplantation Children’s Unit, Hoˆpital de Hautepierre, Strasbourg, **Transplantation and Nephrology Unit, Centre Hospitalier Lyon-Sud, Pierre-Be´nite, and ††Department of Pediatric Nephrology, Hoˆpital des Enfants, and Inserm, U858/I2MR, Department of Renal and Cardiac Remodeling, Toulouse, France; and ‡‡Department of Medicine IV, University of Cologne, Cologne, Germany ABSTRACT Classically, infants with mutations in NPHS1, which encodes nephrin, present with but has since been described in other nephrotic syndrome within the first 3 mo of life (congenital nephrotic syndrome of populations.3–5 Nephrin is a single-pass the Finnish-type), and children with mutations in NPHS2, which encodes podocin, transmembrane protein consisting of present later with steroid-resistant nephrotic syndrome. Recently, however, eight extracellular Ig-like modules, a fi- NPHS2 mutations have been identified in children with congenital nephrotic syn- bronectin type III–like motif, and a cy- drome. Whether NPHS1 mutations similarly account for some cases of childhood tosolic C-terminal tail.
    [Show full text]
  • Nephrin Is Specifically Located at the Slit Diaphragm of Glomerular Podocytes
    Proc. Natl. Acad. Sci. USA Vol. 96, pp. 7962–7967, July 1999 Cell Biology Nephrin is specifically located at the slit diaphragm of glomerular podocytes VESA RUOTSALAINEN*†,PA¨IVI LJUNGBERG*‡§,JORMA WARTIOVAARA¶,ULLA LENKKERI†,MARJO KESTILA¨†, ʈ HANNU JALANKO‡,CHRISTER HOLMBERG‡, AND KARL TRYGGVASON† †Biocenter and Department of Biochemistry, University of Oulu, 90570 Oulu, Finland; ‡Hospital for Children and Adolescents, University Hospital of Helsinki, 00014 Helsinki, Finland; §Department of Bacteriology and Immunology, Haartman Institute and ¶Electron Microscopy Unit, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland; and ʈDivision of Matrix Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden Communicated by Peter A. Reichard, Karolinska Institute, Stockholm, Sweden, April 9, 1999 (Received for review February 12, 1999) ABSTRACT We describe here the size and location of tight junction protein ZO-1 (17) has been localized in the nephrin, the first protein to be identified at the glomerular glomerulus, predominantly to points where the slit diaphragm podocyte slit diaphragm. In Western blots, nephrin antibodies is inserted into the lateral cell membrane of the foot process generated against the two terminal extracellular Ig domains of (18). The ZO-1 protein possibly connects the slit diaphragm, recombinant human nephrin recognized a 180-kDa protein in directly or indirectly, to the cytoskeleton. lysates of human glomeruli and a 150-kDa protein in trans- In numerous primary and secondary diseases of the kidney, fected COS-7 cell lysates. In immunofluorescence, antibodies the filtration barrier is affected, resulting in proteinuria, i.e., to this transmembrane protein revealed reactivity in the leakage of albumin and larger plasma proteins into the urine, glomerular basement membrane region, whereas the podocyte with edema and nephrotic syndrome as a consequence.
    [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]
  • Selective Impairment of Gene Expression and Assembly of Nephrin in Human Diabetic Nephropathy
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Kidney International, Vol. 65 (2004), pp. 2193–2200 Selective impairment of gene expression and assembly of nephrin in human diabetic nephropathy ARIELA BENIGNI,ELENA GAGLIARDINI,SUSANNA TOMASONI,MAURO ABBATE,PIERO RUGGENENTI, RAGHU KALLURI, and GIUSEPPE REMUZZI Mario Negri Institute for Pharmacological Research, Negri Bergamo Laboratories, Bergamo, Italy; Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts; and Division of Nephrology and Dialysis, Azienda Ospedaliera, Ospedali Riuniti, Bergamo, Italy Selective impairment of gene expression and assembly of The nephropathy associated with diabetes is the lead- nephrin in human diabetic nephropathy. ing cause of end-stage renal disease (ESRD) worldwide Background. Recent disclosure of podocyte proteins has un- [1, 2]. In North America, 40% of patients adhering to raveled previously rather mysterious mechanisms that govern glomerular perm-selectivity in health and disease. Here we ad- dialysis transplantation programs in 1998 were diabetic. dressed the role of nephrin, CD2-associated protein (CD2AP), Related treatment costs were estimated at $51,000 per and podocin together with the integrity of the slit diaphragm year (i.e., about $12,000 more than the costs for nondia- in the pathogenesis of proteinuria of patients with diabetes and betics). nephropathy. Diabetic nephropathy, defined as urinary protein ex- Methods. Nephrin mRNA and protein expression were eval- > uated in parallel in adult diabetic patients by in situ hybridiza- cretion rate 0.5 g/24 hours (clinical proteinuria), man- tion and immunohistochemistry. For comparison, nondiabetic ifests within 15 to 20 years after the onset of disease in patients with minimal change nephrosis and normal control 20% to 40% of patients.
    [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]
  • Recombinant Human Kirrel3/NEPH2 Catalog Number: 4910-K3
    Recombinant Human Kirrel3/NEPH2 Catalog Number: 4910-K3 DESCRIPTION Source Mouse myeloma cell line, NS0­derived Leu29­Ala535 & Tyr33­Ala535 & Arg41­Ala535, all with a C­terminal 6­His tag Accession # Q8IZU9 N­terminal Sequence Leu29 Analysis Predicted Molecular 56.1 kDa, 55.7 kDa & 54.7 kDa Mass SPECIFICATIONS SDS­PAGE 65­85 kDa, reducing conditions Activity Measured by the ability of the immobilized protein to support the adhesion of MS­1 mouse pancreatic islet endothelial cells. When 5 x 104 cells/well are added to rhKirrel3 coated plates (30 µg/mL, 100 µL/well), approximately 40%­70% will adhere after 90 minutes at 37° C. Optimal dilutions should be determined by each laboratory for each application. Endotoxin Level <0.10 EU per 1 μg of the protein by the LAL method. Purity >95%, by SDS­PAGE under reducing conditions and visualized by silver stain. Formulation Lyophilized from a 0.2 μm filtered solution in PBS. See Certificate of Analysis for details. PREPARATION AND STORAGE Reconstitution Reconstitute at 100 μg/mL in sterile PBS. Shipping The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. Stability & Storage Use a manual defrost freezer and avoid repeated freeze­thaw cycles. l 12 months from date of receipt, ­20 to ­70 °C as supplied. l 1 month, 2 to 8 °C under sterile conditions after reconstitution. l 3 months, ­20 to ­70 °C under sterile conditions after reconstitution. BACKGROUND Kirrel3 (kin of irregular chiasm­1­like 3), also known as Kirre or NEPH2 (nephrin­like 2), is an ~100 kDa type I transmembrane glycoprotein belonging to the NEPH family within the immunoglobulin superfamily (1, 2).
    [Show full text]
  • Human KIRREL / NEPH1 / KIRREL1 Protein (Fc Tag)
    Human KIRREL / NEPH1 / KIRREL1 Protein (Fc Tag) Catalog Number: 15752-H02H General Information SDS-PAGE: Gene Name Synonym: NEPH1 Protein Construction: A DNA sequence encoding the human KIRREL (NP_060710.3) (Met1-Leu493) was expressed with the Fc region of human IgG1 at the C-terminus. Source: Human Expression Host: HEK293 Cells QC Testing Purity: > 95 % as determined by SDS-PAGE Endotoxin: Protein Description < 1.0 EU per μg of the protein as determined by the LAL method NEPH1 (KIRREL1) belongs to a family of three closely related Stability: transmembrane proteins of the Ig superfamily with a structure similar to that of nephrin. All three Neph proteins share a conserved podocin-binding ℃ Samples are stable for up to twelve months from date of receipt at -70 motif; mutation of a centrally located tyrosine residue dramatically lowers the affinity of Neph1 for podocin. Neph1 triggers AP-1 activation similarly to Gln 17 Predicted N terminal: nephrin but requires the presence of Tec family kinases for efficient Molecular Mass: transactivation. Neph1 consists of a signal peptide, five Ig-like C2-type domains with the middle domain overlapping with a PKD-like domain, an The recombinant human KIRREL/Fc comprises 715 amino acids and has a RGD sequence, a transmembrane domain and a cytoplasmic tail, which is predicted molecular mass of 78.8 kDa. The apparent molecular mass of the expressed in slit diaphragm domains of podocytes and in vertebrate and protein is approximately 96.1 kDa in SDS-PAGE under reducing conditions. invertebrate nervous systems. Neph1 is abundantly expressed in the kidney, specifically expressed in podocytes of kidney glomeruli, and plays a Formulation: significant role in the normal development and function of the glomerular permeability.
    [Show full text]
  • The Intellectual Disability Gene Kirrel3 Regulates Target-Specific Mossy Fiber
    SHORT REPORT The intellectual disability gene Kirrel3 regulates target-specific mossy fiber synapse development in the hippocampus E Anne Martin1†, Shruti Muralidhar1†, Zhirong Wang1, Die´ go Cordero Cervantes1, Raunak Basu1, Matthew R Taylor1, Jennifer Hunter1, Tyler Cutforth2, Scott A Wilke3, Anirvan Ghosh4, Megan E Williams1* 1Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, United States; 2Department of Neurology, Columbia University, New York City, United States; 3Neurobiology Section, Division of Biological Sciences, University of California, San Diego, San Diego, United States; 4Neuroscience Discovery, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland Abstract Synaptic target specificity, whereby neurons make distinct types of synapses with different target cells, is critical for brain function, yet the mechanisms driving it are poorly understood. In this study, we demonstrate Kirrel3 regulates target-specific synapse formation at hippocampal mossy fiber (MF) synapses, which connect dentate granule (DG) neurons to both CA3 and GABAergic neurons. Here, we show Kirrel3 is required for formation of MF filopodia; the structures that give rise to DG-GABA synapses and that regulate feed-forward inhibition of CA3 neurons. Consequently, loss of Kirrel3 robustly increases CA3 neuron activity in developing mice. Alterations in the Kirrel3 gene are repeatedly associated with intellectual disabilities, but the role of *For correspondence: megan. Kirrel3 at synapses remained largely unknown. Our findings demonstrate that subtle synaptic [email protected] changes during development impact circuit function and provide the first insight toward understanding the cellular basis of Kirrel3-dependent neurodevelopmental disorders. † These authors contributed DOI: 10.7554/eLife.09395.001 equally to this work Competing interests: The authors declare that no competing interests exist.
    [Show full text]
  • Supplementary Figure 1. Western Blot Analysis of Total Nephrin Protein Levels in Glomeruli Isolated from Kidneys of Newborn
    Supplementary Figure 1. Western Blot analysis of total Nephrin protein levels in glomeruli isolated from kidneys of newborn CRE[+];NOTCH-IC mice and control littermates. (A) Shown are Western Blot images for Nephrin (upper panel), WT1 (middle panel), and ACTIN (lower panel) in glomerular lysates from three CRE[-];NOTCH-IC (lanes 1-3) and four CRE[+];NOTCH-IC (lanes 4-8) newborn mice. Lysates were prepared from glomeruli isolated from newborn mouse kidneys by iron oxide perfusion followed by magnetic separation. Lysates were separated by SDS-PAGE, transferred onto PVDF membrane, and probed with anti-Nephrin to detect total Nephrin. Membranes were stripped and re-probed with anti-WT to detect WT1 protein, which was used as a surrogate measure of podocyte number to control for sample bias. Membranes were stripped a third time and re-probed with anti-Actin to detect Actin as a loading control. The leftmost lane depicts molecular weight standards. (B) Graphic representation of Nephrin (upper panel) and WT1 (lower panel) protein levels as determined semi-quantitatively by band densitometry. Band density was measured using image analysis software. Values for each lane were normalized to band density for corresponding actin loading control and expressed in arbitrary units (pixel number). White bars depict the mean value of measurements from three CRE[-];NOTCH-IC mice. Black bars show the mean measurement from four CRE[+];NOTCH- IC mice. Error bars denote S.E. (upper panel) No significant difference in total Nephrin protein levels was detected in glomerular lysates from CRE[+];NOTCH-IC mice compared to CRE[- ];NOTCH-IC controls.
    [Show full text]