Related Experiment Video
Updated: Mar 25, 2026
In Vitro Aggregation Assays Using Hyperphosphorylated Tau Protein
Published on: January 2, 2015
Isomerization and Oligomerization of Truncated and Mutated Tau Forms by FKBP52 are Independent Processes
A Kamah1, F X Cantrelle1, I Huvent1
1University of Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, F 59 000 Lille, France.
Abstract:
The aggregation of the neuronal Tau protein is one molecular hallmark of Alzheimer's disease and other related tauopathies, but the precise molecular mechanisms of the aggregation process remain unclear. The FK506 binding protein FKBP52 is able to induce oligomers in the pathogenic Tau P301L mutant and in a truncated form of the wild-type human Tau protein. Here, we investigate whether FKBP52's capacity to induce Tau oligomers depends on its prolyl cis/trans isomerase activity. We find that FKBP52 indeed can isomerize selected prolyl bonds in the different Tau proteins, and that this activity is carried solely by its first FK506 binding domain. Its capacity to oligomerize Tau is, however, not linked to this peptidyl-prolyl isomerase activity. In addition, we identified a novel molecular interaction implying the PHF6 peptide of Tau and the FK1/FK2 domains of FKBP52 independent of FK506 binding; these data point toward a non-catalytic molecular interaction that might govern the effect of FKBP52 on Tau.
Insights
FKBP52 protein can cause Tau protein aggregation, a hallmark of Alzheimer's disease. However, this aggregation effect is not due to FKBP52's isomerase activity but rather a separate molecular interaction.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Tau protein aggregation is a key feature of Alzheimer's disease and tauopathies.
- The molecular mechanisms driving Tau aggregation are not fully understood.
- FKBP52 protein has been shown to induce Tau oligomers.
Purpose of the Study:
- To investigate if FKBP52's ability to induce Tau oligomers is dependent on its prolyl cis/trans isomerase activity.
- To identify the specific domains of FKBP52 involved in Tau interaction.
- To elucidate the molecular mechanisms underlying FKBP52-mediated Tau aggregation.
Main Methods:
- Assessing the prolyl cis/trans isomerase activity of FKBP52 on Tau proteins.
- Mutational analysis of FKBP52 domains.
- Investigating molecular interactions between FKBP52 and Tau peptides (e.g., PHF6).
Main Results:
- FKBP52 exhibits prolyl cis/trans isomerase activity on specific Tau prolyl bonds, localized to its FK1 domain.
- FKBP52's capacity to oligomerize Tau is independent of its isomerase activity.
- A novel interaction between the Tau PHF6 peptide and FKBP52 FK1/FK2 domains was identified, independent of FK506 binding.
Conclusions:
- FKBP52's role in Tau aggregation is likely mediated by a non-catalytic interaction.
- The findings suggest a novel mechanism for Tau oligomerization involving FKBP52.
- This research provides new insights into the molecular basis of tauopathies.
Related Concept Videos
03:03Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
03:03Amyloid Fibrils