Nuclear proteasomes carry a constitutive posttranslational modification which derails SDS-PAGE (but not CTAB-PAGE)
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
We report that subunits of human nuclear proteasomes carry a previously unrecognised, constitutive posttranslational modification. Subunits with this modification are not visualised by SDS-PAGE, which is used in almost all denaturing protein gel electrophoresis. In contrast, CTAB-PAGE readily visualises such modified subunits. Thus, under most experimental conditions, with identical samples, SDS-PAGE yielded gel electrophoresis patterns for subunits of nuclear proteasomes which were misleading and strikingly different from those obtained with CTAB-PAGE. Initial analysis indicates a novel modification of a high negative charge with some similarity to polyADP-ribose, possibly explaining compatibility with (positively-charged) CTAB-PAGE but not (negatively-charged) SDS-PAGE and providing a mechanism for how nuclear proteasomes may interact with chromatin, DNA and other nuclear components.
Date Issued
2014
Date Acceptance
2014-08-24
Citation
Biochimica et Biophysica Acta - Proteins and Proteomics, 2014, 1844, pp.2222-2228
ISSN
1570-9639
Publisher
Elsevier
Start Page
2222
End Page
2228
Journal / Book Title
Biochimica et Biophysica Acta - Proteins and Proteomics
Volume
1844
Issue
12
Copyright Statement
© 2014, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Publication Status
Published
Article Number
12