title: ADAMTSL4, a secreted glycoprotein widely distributed in the eye, binds fibrillin-1 microfibrils and accelerates microfibril biogenesis.
abstract: OBJECTIVE
  ADAMTSL4 mutations cause autosomal recessive isolated ectopia lentis (IEL) and ectopia lentis et pupillae. Dominant FBN1 mutations cause IEL or syndromic ectopia lentis (Marfan syndrome and Weill-Marchesani syndrome). The authors sought to characterize recombinant ADAMTSL4 and the ocular distribution of ADAMTSL4 and to investigate whether ADAMTSL4 influences the biogenesis of fibrillin-1 microfibrils, which compose the zonule.
  
  
  METHODS
  ADAMTSL4 was expressed by the transfection of HEK293F cells. Protein extracts and paraffin sections from human eyes were analyzed by Western blot analysis and by immunoperoxidase staining, respectively. Immunofluorescence was used to evaluate fibrillin-1 deposition in the ECM of fetal bovine nuchal ligament cells after culture in ADAMTSL4-conditioned medium or control medium. Confocal microscopy was performed to investigate ADAMTSL4 and fibrillin-1 colocalization in these cultures.
  
  
  RESULTS
  Western blot analysis identified ADAMTSL4 as a glycoprotein in HEK293F cells and as a major band of 150 kDa in ocular tissues including ciliary body, sclera, cornea, and retina. Immunoperoxidase staining showed a broad ocular distribution of ADAMTSL4, associated with both cells and fibrillar ECM. When cultured in ADAMTSL4-containing medium, fetal bovine nuchal ligament cells showed accelerated fibrillin-1 deposition in ECM. ADAMTSL4 colocalized with fibrillin-1 microfibrils in the ECM of these cells.
  
  
  CONCLUSIONS
  ADAMTSL4 is a secreted glycoprotein that is widely distributed in the human eye. Enhanced fibrillin-1 deposition in the presence of ADAMTSL4 and colocalization of ADAMTSL4 with fibrillin-1 in the ECM of cultured fibroblasts suggest a potential role for ADAMTSL4 in the formation or maintenance of the zonule.
authors: Departments of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
authors: Luis A R
authors: LA
authors: Gabriel
authors: Lauren W
authors: LW
authors: Wang
authors: Hannah
authors: H
authors: Bader
authors: Jason C
authors: JC
authors: Ho
authors: Alana K
authors: AK
authors: Majors
authors: Joe G
authors: JG
authors: Hollyfield
authors: Elias I
authors: EI
authors: Traboulsi
authors: Suneel S
authors: SS
authors: Apte
mesh_terms: D000071096:ADAMTS Proteins; D000818:Animals; D001665:Binding Sites; D015153:Blotting, Western; D002417:Cattle; D002478:Cells, Cultured; D004479:Ectopia Lentis / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D005123:Eye / Q000378:metabolism* / Q000473:pathology; D000071838:Fibrillin-1; D000071837:Fibrillins; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D020894:Microfibrils / Q000235:genetics* / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism*; D018613:Microscopy, Confocal; D011485:Protein Binding; D012313:RNA / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019699:Thrombospondins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D054392:Adipokines
chemical_list: D000071096:ADAMTS Proteins; D016326:Extracellular Matrix Proteins; D000071838:Fibrillin-1; D000071837:Fibrillins; D008840:Microfilament Proteins; D012313:RNA; D019699:Thrombospondins; C486779:ADAMTSL4 protein, human; C000605722:FBN1 protein, human; D054392:Adipokines