title: In situ evaluation of podocin in normal and glomerular diseases.
abstract: BACKGROUND
  Mutations of the NPHS2 gene are responsible for autosomal-recessive steroid-resistant nephrotic syndrome. Its product, podocin, faces the slit diaphragm area with its two ends in the cytoplasm of foot processes.
  
  
  METHODS
  We generated rabbit polyclonal antibodies against conjugated peptides from human podocin N- and C-termini, and studied podocin and synaptopodin using kidney tissues of normal humans and those with glomerular diseases.
  
  
  RESULTS
  Antipodocin antibodies detected the original 42 kD fragment and an extra smaller fragment by Western blot analysis using human isolated mature glomeruli. RNA analysis showed two bands, the original and the other of a decreased length. Immunohistochemically, podocin was detected in a linear pattern along the glomerular capillary loop. Antipodocin antibody (C-terminal) stained the smooth muscles of renal arterioles and aorta. Among 42 patients, podocin was normally expressed in glomeruli in purpura nephritis, IgA nephropathy (IgAN), and minimal-change disease (MCD), while it was either decreased or absent in most subjects with focal segmental glomerulosclerosis (FSGS). The expression of synaptopodin was similar to that of podocin, although some discrepancy existed.
  
  
  CONCLUSIONS
  Although indirect, our data suggest the existence of a vascular isoform of podocin with a different molecular mass. We propose that examination of podocin expression may help differentiate MCD from FSGS.
authors: Department of Pediatrics, Kumamoto University School of Medicine, Kumamoto, Japan.
authors: Izumi
authors: I
authors: Horinouchi
authors: Hitoshi
authors: H
authors: Nakazato
authors: Tomoyasu
authors: T
authors: Kawano
authors: Ken-ichi
authors: K
authors: Iyama
authors: Akio
authors: A
authors: Furuse
authors: Kenji
authors: K
authors: Arizono
authors: Jiro
authors: J
authors: Machida
authors: Tamami
authors: T
authors: Sakamoto
authors: Fumio
authors: F
authors: Endo
authors: Shinzaburo
authors: S
authors: Hattori
mesh_terms: D000293:Adolescent; D000328:Adult; D001011:Aorta / Q000378:metabolism; D001160:Arterioles / Q000378:metabolism; D015153:Blotting, Western; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins; D007674:Kidney Diseases / Q000378:metabolism*; D007678:Kidney Glomerulus / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012079:Renal Circulation; D014018:Tissue Distribution
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C407223:NPHS2 protein; D010446:Peptide Fragments; D012333:RNA, Messenger