DnaJC7 specifically regulates tau seeding
- The University of Texas Southwestern Medical Center, United States
Abstract
Neurodegenerative tauopathies are caused by accumulation of toxic tau protein assemblies. This appears to involve template-based seeding events, whereby tau monomer changes conformation and is recruited to a growing aggregate. Several large families of chaperone proteins, including Hsp70s and J domain proteins (JDPs) cooperate to regulate the folding of intracellular proteins such as tau, but the factors that coordinate this activity are not well known. The JDP DnaJC7 binds tau and reduces its intracellular aggregation. However, it is unknown whether this is specific to DnaJC7 or if other JDPs might be similarly involved. We used proteomics within a cell model to determine that DnaJC7 co-purified with insoluble tau and colocalized with intracellular aggregates. We individually knocked out every possible JDP and tested the effect on intracellular aggregation and seeding. DnaJC7 knockout decreased aggregate clearance and increased intracellular tau seeding. This depended on the ability of the J domain (JD) of DnaJC7 to stimulate Hsp70 ATPase activity, as JD mutations that block this interaction abrogated the protective activity. Disease-associated mutations in the JD and substrate binding site of DnaJC7 also abolished its protective activity. DnaJC7 thus specifically regulates tau aggregation in cooperation with Hsp70.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting file. Source Data files for included Western Blot images are provided as Figure 1 - Supplement 1 - Source Data 1, Figure 2 - Supplement 1 - Source Data 1, Figure 3 -Supplement 1 - Source Data 1, and Figure 5 - Supplement 1 - Source Data 1. Source data files have been provided for Figures 1 (Source Data 1 and 2) and 2 (Source Data 3) on Dryad at: https://doi.org/10.5061/dryad.fj6q57402FCS files are deposited on Cytobank at: https://community.cytobank.org/cytobank/projects/1505
-
DnaJC7 specifically regulates tau seedingDryad Digital Repository, doi:10.5061/dryad.fj6q57402.
Article and author information
Author details
Barbara Elena Stopschinski
Charles L White III
Lukasz A Joachimiak
Funding
National Institute on Aging (RF1AG078888)
- Valerie Ann Perez
- Vishruth Mullapudi
- Lukasz A Joachimiak
National Institute on Aging (3R01AG048678)
- Valerie Ann Perez
- David W Sanders
- Ayde Mendoza-Oliva
- Barbara Elena Stopschinski
- Marc I Diamond
National Institute on Aging (1RF1AG059689)
- Valerie Ann Perez
- David W Sanders
- Ayde Mendoza-Oliva
- Barbara Elena Stopschinski
- Charles L White III
- Marc I Diamond
National Institute on Aging (1RF1AG065407)
- Valerie Ann Perez
- David W Sanders
- Ayde Mendoza-Oliva
- Barbara Elena Stopschinski
- Vishruth Mullapudi
- Lukasz A Joachimiak
- Marc I Diamond
McCune Foundation
- Charles L White III
Winspear Family Center for Research on the Neuropathology of Alzheimer's Disease
- Charles L White III
Chan Zuckerberg Initiative (2018-191983)
- Charles L White III
- Lukasz A Joachimiak
- Marc I Diamond
Chan Zuckerberg Initiative (2021-237348)
- Charles L White III
- Lukasz A Joachimiak
- Marc I Diamond
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Perez et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 1,086
- views
-
- 173
- downloads
-
- 7
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
DnaJC7 specifically regulates tau seeding
eLife 12:e86936.
https://doi.org/10.7554/eLife.86936
Further reading
-
- Biochemistry and Chemical Biology
- Structural Biology and Molecular Biophysics
Dynamic conformational and structural changes in proteins and protein complexes play a central and ubiquitous role in the regulation of protein function, yet it is very challenging to study these changes, especially for large protein complexes, under physiological conditions. Here, we introduce a novel isobaric crosslinker, Qlinker, for studying conformational and structural changes in proteins and protein complexes using quantitative crosslinking mass spectrometry. Qlinkers are small and simple, amine-reactive molecules with an optimal extended distance of ~10 Å, which use MS2 reporter ions for relative quantification of Qlinker-modified peptides derived from different samples. We synthesized the 2-plex Q2linker and showed that the Q2linker can provide quantitative crosslinking data that pinpoints key conformational and structural changes in biosensors, binary and ternary complexes composed of the general transcription factors TBP, TFIIA, and TFIIB, and RNA polymerase II complexes.
-
- Biochemistry and Chemical Biology
- Stem Cells and Regenerative Medicine
Human induced pluripotent stem cells (hiPSCs) have great potential to be used as alternatives to embryonic stem cells (hESCs) in regenerative medicine and disease modelling. In this study, we characterise the proteomes of multiple hiPSC and hESC lines derived from independent donors and find that while they express a near-identical set of proteins, they show consistent quantitative differences in the abundance of a subset of proteins. hiPSCs have increased total protein content, while maintaining a comparable cell cycle profile to hESCs, with increased abundance of cytoplasmic and mitochondrial proteins required to sustain high growth rates, including nutrient transporters and metabolic proteins. Prominent changes detected in proteins involved in mitochondrial metabolism correlated with enhanced mitochondrial potential, shown using high-resolution respirometry. hiPSCs also produced higher levels of secreted proteins, including growth factors and proteins involved in the inhibition of the immune system. The data indicate that reprogramming of fibroblasts to hiPSCs produces important differences in cytoplasmic and mitochondrial proteins compared to hESCs, with consequences affecting growth and metabolism. This study improves our understanding of the molecular differences between hiPSCs and hESCs, with implications for potential risks and benefits for their use in future disease modelling and therapeutic applications.
