Tau polarizes an aging transcriptional signature to excitatory neurons and glia
Abstract
Aging is a major risk factor for Alzheimer’s disease (AD), and cell-type vulnerability underlies its characteristic clinical manifestations. We have performed longitudinal, single-cell RNA-sequencing in Drosophila with pan-neuronal expression of human tau, which forms AD neurofibrillary tangle pathology. Whereas tau- and aging-induced gene expression strongly overlap (93%), they differ in the affected cell types. In contrast to the broad impact of aging, tau-triggered changes are strongly polarized to excitatory neurons and glia. Further, tau can either activate or suppress innate immune gene expression signatures in a cell type-specific manner. Integration of cellular abundance and gene expression pinpoints Nuclear Factor Kappa B signaling in neurons as a marker for cellular vulnerability. We also highlight the conservation of cell type-specific transcriptional patterns between Drosophila and human postmortem brain tissue. Overall, our results create a resource for dissection of dynamic, age-dependent gene expression changes at cellular resolution in a genetically tractable model of tauopathy.
Data availability
All original single cell sequencing data have been uploaded to the Accelerating Medicines Parternship (AMP)-AD Knowledge Portal on Synapse and can be accessed through the DOI: https://doi.org/10.7303/syn35798807.1.
-
The Single-cell transcriptomic analysis of Alzheimer's disease (snRNAseqPFC_BA10) StudyAD Knowledge Portal: syn2580853.
-
A single-cell transcriptome atlas of the ageing Drosophila brainNCBI Gene Expression Omnibus, GSE107451.
-
Neuronal diversity and convergence in a visual system developmental atlasNCBI Gene Expression Omnibus, GSE142789.
Article and author information
Author details
Funding
National Institute on Aging (R01AG057339)
- Zhandong Liu
- Juan Botas
- Joshua M Shulman
Huffington Foundation
- Zhandong Liu
- Juan Botas
- Joshua M Shulman
McGee Family Foundation
- Joshua M Shulman
Duncan Neurological Research Institute
- Zhandong Liu
- Ismael Al-Ramahi
- Juan Botas
- Joshua M Shulman
Effie Marie Caine Endowed Chair for Alzheimer's Research
- Joshua M Shulman
National Institute on Aging (R01AG053960)
- Joshua M Shulman
National Institute on Aging (U01AG061357)
- Joshua M Shulman
National Institute on Aging (U01AG046161)
- Joshua M Shulman
Eunice Kennedy Shriver National Institute of Child Health and Human Development (P50HD103555)
- Joshua M Shulman
National Institutes of Health (S10OD023469)
- Joshua M Shulman
National Institutes of Health (S10OD025240)
- Joshua M Shulman
Cancer Prevention and Research Institute of Texas (RP200504)
- Joshua M Shulman
Parkinson's Foundation (PF-PRF-830012)
- Hui Ye
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Wu 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
-
- 1,805
- views
-
- 192
- downloads
-
- 5
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
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)
Further reading
-
- Computational and Systems Biology
- Genetics and Genomics
Untranslated regions (UTRs) contain crucial regulatory elements for RNA stability, translation and localization, so their integrity is indispensable for gene expression. Approximately 3.7% of genetic variants associated with diseases occur in UTRs, yet a comprehensive understanding of UTR variant functions remains limited due to inefficient experimental and computational assessment methods. To systematically evaluate the effects of UTR variants on RNA stability, we established a massively parallel reporter assay on 6555 UTR variants reported in human disease databases. We examined the RNA degradation patterns mediated by the UTR library in two cell lines, and then applied LASSO regression to model the influential regulators of RNA stability. We found that UA dinucleotides and UA-rich motifs are the most prominent destabilizing element. Gain of UA dinucleotide outlined mutant UTRs with reduced stability. Studies on endogenous transcripts indicate that high UA-dinucleotide ratios in UTRs promote RNA degradation. Conversely, elevated GC content and protein binding on UA dinucleotides protect high-UA RNA from degradation. Further analysis reveals polarized roles of UA-dinucleotide-binding proteins in RNA protection and degradation. Furthermore, the UA-dinucleotide ratio of both UTRs is a common characteristic of genes in innate immune response pathways, implying a coordinated stability regulation through UTRs at the transcriptomic level. We also demonstrate that stability-altering UTRs are associated with changes in biobank-based health indices, underscoring the importance of precise UTR regulation for wellness. Our study highlights the importance of RNA stability regulation through UTR primary sequences, paving the way for further exploration of their implications in gene networks and precision medicine.
-
- Genetics and Genomics
Flavin-containing monooxygenases (FMOs) are a conserved family of xenobiotic enzymes upregulated in multiple longevity interventions, including nematode and mouse models. Previous work supports that C. elegans fmo-2 promotes longevity, stress resistance, and healthspan by rewiring endogenous metabolism. However, there are five C. elegans FMOs and five mammalian FMOs, and it is not known whether promoting longevity and health benefits is a conserved role of this gene family. Here, we report that expression of C. elegans fmo-4 promotes lifespan extension and paraquat stress resistance downstream of both dietary restriction and inhibition of mTOR. We find that overexpression of fmo-4 in just the hypodermis is sufficient for these benefits, and that this expression significantly modifies the transcriptome. By analyzing changes in gene expression, we find that genes related to calcium signaling are significantly altered downstream of fmo-4 expression. Highlighting the importance of calcium homeostasis in this pathway, fmo-4 overexpressing animals are sensitive to thapsigargin, an ER stressor that inhibits calcium flux from the cytosol to the ER lumen. This calcium/fmo-4 interaction is solidified by data showing that modulating intracellular calcium with either small molecules or genetics can change expression of fmo-4 and/or interact with fmo-4 to affect lifespan and stress resistance. Further analysis supports a pathway where fmo-4 modulates calcium homeostasis downstream of activating transcription factor-6 (atf-6), whose knockdown induces and requires fmo-4 expression. Together, our data identify fmo-4 as a longevity-promoting gene whose actions interact with known longevity pathways and calcium homeostasis.