Cell and Tissue Research

, Volume 346, Issue 3, pp 347–359 | Cite as

Protein myozap — a late addition to the molecular ensembles of various kinds of adherens junctions

  • Steffen Rickelt
  • Caecilia Kuhn
  • Stefanie Winter-Simanowski
  • Ralf Zimbelmann
  • Norbert Frey
  • Werner Wilhelm FrankeEmail author
Regular Article


The protein myozap, a polypeptide of 54 kDa, has recently been identified as a component of the cytoplasmic plaques of the composite junctions (areae compositae) in the myocardiac intercalated disks and of the adherens junctions (AJs) in vascular endothelia. Now we report that using very sensitive new antibodies and drastic localization methods, we have also identified this protein as a component of the AJ plaques in simple and complex epithelia, in the adluminal cell layer of the transitional epithelium of the urinary tract and in certain cell layers of diverse stratified epithelia, including gingiva, tongue, pharynx and esophagus, cervix, vagina and epidermis. Myozap has not been identified in desmosomal and tight junction plaques. We have also detected protein myozap in AJ structures of carcinomas. The discovery of a novel major protein in AJ plaques now calls for re-examinations of molecular interactions in AJ formation and maintenance and also offers a new marker for diagnostic immunocytochemistry. We also discuss the need for progressive unravelling, extractive treatments and buffer rinses of sections and cultured cells to reveal obscured or masked antigens, before definitive negative conclusions in immunohistochemistry can be made.


Adherens junctions Epithelial cells Junction plaques Protein myozap Immunohistochemistry 



adherens junction


isoelectric focusing


tight junction



We thank Christine Grund for excellent technical assistance. This work was supported by the Federal Ministry for Research and Technology (BMBF; to W.W.F.; START-MSC; grant: 01GN0942).


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Steffen Rickelt
    • 1
    • 2
  • Caecilia Kuhn
    • 1
    • 2
  • Stefanie Winter-Simanowski
    • 1
  • Ralf Zimbelmann
    • 1
  • Norbert Frey
    • 3
  • Werner Wilhelm Franke
    • 1
    • 2
    Email author
  1. 1.Helmholtz Group for Cell BiologyGerman Cancer Research Center (DKFZ)HeidelbergGermany
  2. 2.Progen BiotechnikHeidelbergGermany
  3. 3.Internal Medicine and Cardiology, Department of Cardiology and AngiologyUniversity Hospital KielKielGermany

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