Conformational modulation mediated by polyglutamine expansion in CAG repeat expansion disease-associated proteins.

Abstract

We have previously reported TR-FRET based immunoassays to detect a conformational change imparted on huntingtin protein by the polyglutamine expansion, which we confirmed using biophysical methodologies. Using these immunoassays, we now report that polyglutamine expansion influences the conformational properties of other polyglutamine disease proteins, exemplified by the androgen receptor (associated with spinal bulbar muscular atrophy) and TATA binding protein (associated with spinocerebellar ataxia 17). Using artificial constructs bearing short or long polyglutamine expansions or a multimerized, unrelated epitope (mimicking the increase in anti-polyglutamine antibody epitopes present in polyglutamine repeats of increasing length) we confirmed that the conformational TR-FRET based immunoassay detects an intrinsic conformational property of polyglutamine repeats. The TR-FRET based conformational immunoassay may represent a rapid, scalable tool to identify modulators of polyglutamine-mediated conformational change in different proteins associated with CAG triplet repeat disorders.

• Authors: Margherita Verani, Maria Bustamante, Paola Martufi, Manuel Daldin, Cristina Cariulo, Lucia Azzollini, Valentina Fodale, Francesca Puglisi, Andreas Weiss, Douglas Macdonald, Lara Petricca, Andrea Caricasole
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 478 Issue 2 Pg. 949-55 (09 16 2016) ISSN: 1090-2104 [Electronic] United States
• PMID: 27520369 (Publication Type: Journal Article)
• Copyright: Copyright © 2016 Elsevier Inc. All rights reserved.

Chemical References

• Cell Extracts
• Peptides
• polyglutamine

Topics

• Cell Extracts
• Disease (genetics)
• Fluorescence Resonance Energy Transfer
• HEK293 Cells
• Humans
• Immunoassay
• Molecular Conformation
• Peptides (metabolism)
• Transfection
• Trinucleotide Repeat Expansion (genetics)