Autoantibody to RNA polymerase I in scleroderma sera

J Clin Invest. 1987 Jan;79(1):65-72. doi: 10.1172/JCI112809.


Autoantibodies to components of the nucleolus are a unique serological feature of patients with scleroderma. There are autoantibodies of several specificities; one type produces a speckled pattern of nucleolar staining in immunofluorescence. In actinomycin D and 5,6-dichloro-beta-D-ribofuranosylbenzimidazole-treated Vero cells, staining was restricted to the fibrillar and not the granular regions. By double immunofluorescence, specific rabbit anti-RNA polymerase I antibodies stained the same fibrillar structures in drug-segregated nucleoli as scleroderma sera. Scleroderma sera immunoprecipitated 13 polypeptides from [35S]methionine-labeled HeLa cell extract with molecular weights ranging from 210,000 to 14,000. Similar polypeptides were precipitated by rabbit anti-RNA polymerase I antibodies, and their common identities were confirmed in immunoabsorption experiments. Microinjection of purified IgG from a patient with speckled nucleolar staining effectively inhibited ribosomal RNA transcription. Autoantibodies to RNA polymerase I were restricted to certain patients with scleroderma and were not found in other autoimmune diseases.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antibody Specificity
  • Autoantibodies / immunology*
  • Cell Nucleolus / immunology
  • Epitopes
  • Humans
  • Immunologic Techniques
  • Microscopy, Electron
  • Molecular Weight
  • Phosphoproteins / immunology
  • RNA Polymerase I / immunology*
  • Scleroderma, Systemic / immunology*


  • Autoantibodies
  • Epitopes
  • Phosphoproteins
  • RNA Polymerase I