Visualization of Hidden Epitopes at the Inactive X Chromosome

  • Emma R. StewartEmail author
  • Dawn CoverleyEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1861)


Immunodetection of nuclear antigens is often complicated by epitope masking, so that proteins known to function in the nucleus are sometimes not easily detected at their sites of action. Moreover, protein populations that are detected before unmasking can be very different to those seen after removal of nucleic acids. This is particularly true for components of the nuclear matrix, including those known to function at the inactive X chromosome. Here we describe an unmasking protocol that reveals previously undetected proteins at the inactive X chromosome in mouse fibroblasts.

Key words

Unmasking nuclear proteins Nuclear matrix Immunofluorescence SAF-A CIZ1 Inactive X chromosome 



We are grateful to Barbora Kriukelyte for the PTBP1 antibody staining and Justin Ainscough for his comments. This work was funded by ERS PhD scholarship as part of BBSRC White Rose Doctoral Training Partnership grant BB/M011151/1.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of BiologyUniversity of YorkWentworth WayUK

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