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Riedel, C. G.

Publications and source records attributed to Riedel, C. G..

7 recordsLinked to original sources

Pasta, an age-shift transcriptomic clock, maps the chemical and genetic determinants of aging and rejuvenation

With the growing burden of age-related diseases, understanding and modulating the aging process has become a priority. Transcriptomic aging clocks (TACs) can track biological age but remain limited by platform dependence, tissue specificity, or restricted accessibility. To address this, we developed Pasta, a robust and broadly applicable human TAC built using a novel age-shift learning framework. Pasta accurately predicted relative age across diverse tissues, data types, including bulk and single-cell RNA-Seq as well as microarray data, and species. Its predictions aligned with senescent and stem-like cellular states, with model coefficients enriched for p53 and DNA damage response pathways. Pastas age scores correlated with tumor grade and patient survival in several cancer types, indicating potential clinical relevance. Applied to the Connectivity Map L1000 dataset, Pasta identified both established and previously unrecognized age-modulatory compounds and genetic perturbations, highlighting mitochondrial translation and mRNA splicing as key determinants of cellular propensity for aging and rejuvenation, respectively. Experimental validation confirmed pralatrexate as a potent senescence inducer and piperlongumine as a rejuvenating agent. Together, these findings establish Pasta as a versatile and accessible tool for aging research and therapeutic discovery.

bioinformatics↗

A progeria-associated BAF-1 mutation modulates gene expression and accelerates aging in C. elegans

Alterations in the nuclear envelope are linked to a variety of rare diseases termed laminopathies. These include both tissue specific and systemic diseases. A single amino acid substitution in human barrier to autointegration factor (BAF) at position 12 (A12T) causes Nestor-Guillermo Progeria Syndrome (NGPS). This premature ageing condition affects a variety of tissues, leading to growth retardation and severe skeletal defects, including scoliosis. Taking advantage of the conservation between human and C. elegans BAF proteins, we have modified the baf-1 locus in C. elegans to mimic the human NGPS mutation (baf-1(G12T)). In this work, we characterized the phenotypes caused by the G12T mutation at molecular, cellular, and organismal scale. We found that the mutation induced multiple phenotypes related to fertility, lifespan, and stress resistance. Importantly, nuclear morphology deteriorated faster during aging in baf-1(G12T), relative to wild-type animals, coinciding with an important hallmark of cells from progeria patients. Nuclear envelope accumulation of lamin and emerin was reduced whereas localization of BAF-1(G12T) was similar to wild-type BAF-1. We determined the chromatin binding profiles for wild-type and mutant BAF-1 and performed transcriptome analyses through tissue-specific DamID. Although the global profiles for wild-type and G12T BAF-1 resembled one another, we also identified many discrete regions with altered BAF-1(G12T) association. Most genes deregulated by the baf-1(G12T) mutation were characterized by a change in BAF-1 association, suggesting a direct relation between association of a gene to BAF-1 and its expression. We conclude that C. elegans is a relevant model to understand how a mutation in an essential protein expressed throughout development triggers the appearance of symptoms in early childhood.

cell biology↗

Cactus: a user-friendly and reproducible ATAC-Seq and mRNA-Seq analysis pipeline for data preprocessing, differential analysis, and enrichment analysis

The ever decreasing cost of Next-Generation Sequencing coupled with the emergence of efficient and reproducible analysis pipelines has rendered genomic methods more accessible. However, downstream analyses are basic or missing in most workflows, creating a significant barrier for non-bioinformaticians. To help close this gap, we developed Cactus, an end-to-end pipeline for analyzing ATAC-Seq and mRNA-Seq data, either separately or jointly. Its Nextflow-, container-, and virtual environment-based architecture ensures efficient and reproducible analyses. Cactus preprocesses raw reads, conducts differential analyses between conditions, and performs enrichment analyses in various databases, including DNA-binding motifs, ChIP-Seq binding sites, chromatin states, and ontologies. We demonstrate the utility of Cactus in a multi-modal and multi-species case study as well as by showcasing its unique capabilities as compared to other ATAC-Seq pipelines. In conclusion, Cactus can assist researchers in gaining comprehensive insights from chromatin accessibility and gene expression data in a quick, user-friendly, and reproducible manner.

bioinformatics↗

The chromatin factors SET-26 and HCF-1 oppose the histone deacetylase HDA-1 in longevity and gene regulation in C. elegans

SET-26, HCF-1, and HDA-1 are highly conserved chromatin factors with key roles in development and aging. Here we present mechanistic insights into how these factors regulate gene expression and modulate longevity in C. elegans. We show that SET-26 and HCF-1 cooperate to regulate a common set of genes, and both antagonize the histone deacetylase HDA-1 to limit longevity. We propose a model in which SET-26 recruits HCF-1 to chromatin in somatic cells, where they stabilize each other at the promoters of a subset of genes, particularly mitochondrial function genes, and regulate their expression. HDA-1 opposes SET-26 and HCF-1 on the regulation of a subset of their common target genes and in longevity. Our findings suggest that SET-26, HCF-1, and HDA-1 comprise a mechanism to fine-tune gene expression and longevity and likely have important implications for the mechanistic understanding of how these factors function in diverse organisms, particularly in aging biology.

genomics↗

SIN3 acts in distinct complexes to regulate the germline transcriptional program in C. elegans

The SIN3 transcriptional coregulator influences gene expression through multiple interactions that include histone deacetylases (HDACs). Haploinsufficiency and mutations in SIN3 are the underlying cause of Witteveen-Kolk syndrome and related intellectual disability (ID)/autism syndromes, emphasizing its key role in development. However, little is known about the diversity of its interactions and functions in developmental processes. Here we show that loss of SIN-3, the single SIN3 homologue in Caenorhabditis elegans, results in maternal effect sterility associated with deregulation of the germline transcriptome, including desilencing of X-linked genes. We identify at least two distinct SIN3 complexes containing specific HDACs, and show that they differentially contribute to fertility. Single cell smFISH reveals that in sin-3 mutants, the X chromosome becomes re-expressed prematurely and in a stochastic manner in individual germ cells. Furthermore, we identify histone residues whose acetylation increases in the absence of SIN3. Together, this work provides a powerful framework for the in vivo study of SIN3 and associated proteins.

genetics↗

A multiparametric anti-aging CRISPR screen uncovers a role for BAF in protein translation

Progeria syndromes are very rare, incurable premature aging conditions recapitulating most aging features. Here, we report the first whole genome, multiparametric CRISPR anti-aging screen, identifying 43 new genes that can reverse multiple aging phenotypes in progeria. The screen was implemented in fibroblasts from Nestor- Guillermo Progeria Syndrome (NGPS) patients, carrying a homozygous p.Ala12Thr mutation in barrier-to-autointegration factor (BAF A12T). The hits were enriched for genes involved in protein translation, protein and RNA transport and osteoclast formation. We further confirmed that BAF A12T drives increased protein translation and translational errors that could directly contribute to premature aging in patients. This work has highlighted the power of multiparametric whole genome synthetic rescue screens to identify new anti-aging genes and uncover novel biology behind progeria-associated cellular dysfunction. One-Sentence SummaryA whole genome multiparametric screen in progeria identifies new pathways that can reverse cellular aging phenotypes.

molecular biology↗

Transcriptomics-based screening identifies pharmacological inhibition of Hsp90 as a means to defer aging

Aging is a major risk factor for human morbidity and mortality. Thus, the identification of compounds that defer aging, also known as geroprotectors, could greatly improve our health and promote a longer life. Here we screened for geroprotectors, employing the power of human transcriptomics to predict biological age. We used age-stratified human tissue transcriptomes to generate machine-learning-based classifiers capable of distinguishing transcriptomes from young versus old individuals. Then we applied these classifiers to transcriptomes induced by 1300 different compounds in human cell lines and ranked these compounds by their ability to induce a youthful transcriptional state. Besides known geroprotectors, several new candidate compounds emerged from this ranking. Testing these in the model organism C. elegans, we identified two Hsp90 inhibitors, Monorden and Tanespimycin, which substantially extended the animals lifespan and improved their health. Hsp90 inhibition specifically induces the expression of heat shock proteins, known to improve protein homeostasis. Consistently, Monorden treatment improved the survival of C. elegans under proteotoxic stress, and its lifespan benefits were fully dependent on the master regulator of the cytosolic unfolded protein response, the transcription factor HSF-1. Taken together, we present an innovative transcriptomics-based screening approach to discover aging-preventive compounds and highlight Hsp90 inhibitors as powerful geroprotectors that could be of great value, to target the aging process in humans.

cell biology↗