Skip to main content
NCBI home page
The Journal of Experimental Medicine logoLink to The Journal of Experimental Medicine
. 1988 Jun 1;167(6):1791–1799. doi: 10.1084/jem.167.6.1791

The autoepitope of the 74-kD mitochondrial autoantigen of primary biliary cirrhosis corresponds to the functional site of dihydrolipoamide acetyltransferase

PMCID: PMC2189671  PMID: 2455013

Abstract

Autoantibodies to mitochondrial antigens are characteristic of the autoimmune liver disease primary biliary cirrhosis (PBC), but the precise antigenic determinants recognized by these antibodies have not been defined. Recently, our laboratory identified a 1,370-bp rat liver cDNA clone that coded for a polypeptide recognized specifically by sera from patients with PBC but not by sera from patients with other forms of liver disease. This recombinant protein was identified as the 74-kD M2 mitochondrial inner membrane autoantigen, now known to be dihydrolipoamide acetyltransferase. In the present study, we have identified a 603-bp fragment that codes for a polypeptide containing all of the autoreactivity of the original clone. In addition, based on hydrophobicity/hydrophilicity plots of the amino acid sequence of this polypeptide segment, several peptides were synthesized and tested for reactivity by an inhibition assay using sera from patients with PBC. One peptide, defined by the amino acids AEIETDKATIGFEVQEEGYL, absorbed serum reactivity to the protein product of the original clone. Of particular interest was the finding that this peptide contains the lipoic acid binding site KATIGF of the dihydrolipoamide acetyltransferase found in the inner mitochondrial membrane. Thus, it appears that for this autoantigen, the target of the autoantibodies corresponds to a functional site of the dihydrolipoamide acetyltransferase.

Full Text

The Full Text of this article is available as a PDF (586.7 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alderuccio F., Toh B. H., Barnett A. J., Pedersen J. S. Identification and characterization of mitochondria autoantigens in progressive systemic sclerosis: identity with the 72,000 dalton autoantigen in primary biliary cirrhosis. J Immunol. 1986 Sep 15;137(6):1855–1859. [PubMed] [Google Scholar]
  2. Benjamin D. C., Berzofsky J. A., East I. J., Gurd F. R., Hannum C., Leach S. J., Margoliash E., Michael J. G., Miller A., Prager E. M. The antigenic structure of proteins: a reappraisal. Annu Rev Immunol. 1984;2:67–101. doi: 10.1146/annurev.iy.02.040184.000435. [DOI] [PubMed] [Google Scholar]
  3. Berg P. A., Klein R., Lindenborn-Fotinos J., Klöppel W. ATPase-associated antigen (M2): marker antigen for serological diagnosis of primary biliary cirrhosis. Lancet. 1982 Dec 25;2(8313):1423–1426. doi: 10.1016/s0140-6736(82)91327-7. [DOI] [PubMed] [Google Scholar]
  4. Berg P. A., Klein R. Mitochondrial antigens and autoantibodies: from anti-M1 to anti-M9. Klin Wochenschr. 1986 Oct 1;64(19):897–909. doi: 10.1007/BF01728613. [DOI] [PubMed] [Google Scholar]
  5. Bradford A. P., Howell S., Aitken A., James L. A., Yeaman S. J. Primary structure around the lipoate-attachment site on the E2 component of bovine heart pyruvate dehydrogenase complex. Biochem J. 1987 Aug 1;245(3):919–922. doi: 10.1042/bj2450919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chambers J. C., Keene J. D. Isolation and analysis of cDNA clones expressing human lupus La antigen. Proc Natl Acad Sci U S A. 1985 Apr;82(7):2115–2119. doi: 10.1073/pnas.82.7.2115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gershwin M. E., Coppel R. L., Bearer E., Peterson M. G., Sturgess A., Mackay I. R. Molecular cloning of the liver-specific rat F antigen. J Immunol. 1987 Dec 1;139(11):3828–3833. [PubMed] [Google Scholar]
  8. Gershwin M. E., Mackay I. R., Sturgess A., Coppel R. L. Identification and specificity of a cDNA encoding the 70 kd mitochondrial antigen recognized in primary biliary cirrhosis. J Immunol. 1987 May 15;138(10):3525–3531. [PubMed] [Google Scholar]
  9. Green N., Alexander H., Olson A., Alexander S., Shinnick T. M., Sutcliffe J. G., Lerner R. A. Immunogenic structure of the influenza virus hemagglutinin. Cell. 1982 Mar;28(3):477–487. doi: 10.1016/0092-8674(82)90202-1. [DOI] [PubMed] [Google Scholar]
  10. Hirayu H., Seto P., Magnusson R. P., Filetti S., Rapoport B. Molecular cloning and partial characterization of a new autoimmune thyroid disease-related antigen. J Clin Endocrinol Metab. 1987 Mar;64(3):578–584. doi: 10.1210/jcem-64-3-578. [DOI] [PubMed] [Google Scholar]
  11. Hopp T. P. Protein surface analysis. Methods for identifying antigenic determinants and other interaction sites. J Immunol Methods. 1986 Apr 3;88(1):1–18. doi: 10.1016/0022-1759(86)90045-1. [DOI] [PubMed] [Google Scholar]
  12. Hopp T. P., Woods K. R. A computer program for predicting protein antigenic determinants. Mol Immunol. 1983 Apr;20(4):483–489. doi: 10.1016/0161-5890(83)90029-9. [DOI] [PubMed] [Google Scholar]
  13. Kaplan M. M. Primary biliary cirrhosis. Adv Intern Med. 1987;32:359–377. [PubMed] [Google Scholar]
  14. Kemp D. J., Coppel R. L., Cowman A. F., Saint R. B., Brown G. V., Anders R. F. Expression of Plasmodium falciparum blood-stage antigens in Escherichia coli: detection with antibodies from immune humans. Proc Natl Acad Sci U S A. 1983 Jun;80(12):3787–3791. doi: 10.1073/pnas.80.12.3787. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Kyte J., Doolittle R. F. A simple method for displaying the hydropathic character of a protein. J Mol Biol. 1982 May 5;157(1):105–132. doi: 10.1016/0022-2836(82)90515-0. [DOI] [PubMed] [Google Scholar]
  16. Packman L. C., Hale G., Perham R. N. Repeating functional domains in the pyruvate dehydrogenase multienzyme complex of Escherichia coli. EMBO J. 1984 Jun;3(6):1315–1319. doi: 10.1002/j.1460-2075.1984.tb01969.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Packman L. C., Stanley C. J., Perham R. N. Temperature-dependence of intramolecular coupling of active sites in pyruvate dehydrogenase multienzyme complexes. Biochem J. 1983 Aug 1;213(2):331–338. doi: 10.1042/bj2130331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Rüther U., Müller-Hill B. Easy identification of cDNA clones. EMBO J. 1983;2(10):1791–1794. doi: 10.1002/j.1460-2075.1983.tb01659.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Sanger F. Determination of nucleotide sequences in DNA. Science. 1981 Dec 11;214(4526):1205–1210. doi: 10.1126/science.7302589. [DOI] [PubMed] [Google Scholar]
  20. Sweet R. M., Eisenberg D. Correlation of sequence hydrophobicities measures similarity in three-dimensional protein structure. J Mol Biol. 1983 Dec 25;171(4):479–488. doi: 10.1016/0022-2836(83)90041-4. [DOI] [PubMed] [Google Scholar]
  21. Wieben E. D., Rohleder A. M., Nenninger J. M., Pederson T. cDNA cloning of a human autoimmune nuclear ribonucleoprotein antigen. Proc Natl Acad Sci U S A. 1985 Dec;82(23):7914–7918. doi: 10.1073/pnas.82.23.7914. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from The Journal of Experimental Medicine are provided here courtesy of The Rockefeller University Press

RESOURCES