Biology subjects

Suh, Y.

Publications and source records attributed to Suh, Y..

At least 19 recordsLinked to original sources

bioRxiv2026

The microbial soy metabolite S-equol mitigates cadmium neurotoxicity in mice

Environmental exposures are major but understudied determinants of chronic disease. Cadmium is a pervasive toxic metal encountered through diet and tobacco smoke that has been associated with cognitive impairment and Alzheimer's disease mortality, yet strategies to mitigate its neurotoxicity remain limited. S-equol is a gut microbial metabolite of soy daidzein that crosses the blood brain barrier and preferentially activates estrogen receptor beta. Here, we show that cadmium disrupts an axis linking the equol producing gut bacterium Adlercreutzia equolifaciens to circulating S-equol and hippocampal estrogen receptor expression in mice, that S-equol attenuates cadmium-induced cytotoxicity and restores neuronal, glutamatergic and synaptic transcriptional programs in mouse neural progenitor cells, and that circulating S-equol in older humans is lower in apolipoprotein E4 carriers and covaries with body mass index, identifying S-equol as a microbiome-derived, host-modulated candidate countermeasure against cadmium neurotoxicity.

neuroscience↗

bioRxiv2026

A longevity-associated ubiquitin E3 ligase UBE3C governs lamin B1 homeostasis through selective autophagy and delay senescence

Nuclear lamina integrity is fundamental to cellular homeostasis across the lifespan 1, and its progressive deterioration is closely linked to human aging 2. Yet, the regulatory mechanism that govern this decline and how they might be counteracted in long-lived individuals remain poorly defined. Here, by combining whole-exome sequencing of Ashkenazi Jewish centenarians with GTEx transcriptomes, we identify ubiquitin E3 ligase UBE3C strongly associated with exceptional longevity and progressively declines with age across human tissues. UBE3C knockdown triggers premature senescence and destabilizes key nuclear lamina components Lamin B1 (LMNB1) and Lamin B receptor (LBR), while the longevity-associated UBE3C variant delays senescence and preserves LMNB1/LBR expression. Mechanistically, UBE3C interacts directly with LMNB1/LBR and modulates their abundance via selective autophagy. Notably, we uncover the ER- resident autophagy trigger CKAP4 3 bridges UBE3C and LMNB1. UBE3C loss enhances LMNB1-CKAP4 binding, linking nuclear lamina turnover to autophagy. Together, our findings establish UBE3C as a central guardian of nuclear lamina maintenance during senescence and offering novel insights into interventions against age-related nuclear lamina deterioration.

cell biology↗

bioRxiv2026

Identification of functional non-coding variants affecting Alzheimer's disease risk by Massively Parallel Reporter Assay

The majority of genetic risk variants for late-onset Alzheimers disease (LOAD) reside within non-coding genomic regions, suggesting they exert pathogenic effects by disrupting transcriptional regulatory programs. To systematically identify functional variants, we performed an unbiased, high-throughput Massively Parallel Reporter Assay (MPRA) in the THP-1 human monocytic cell line, screening 2,231 SNPs across 24 LOAD GWAS loci. We identified 62 variants exhibiting significant allele-specific transcriptional regulatory output, including rs636317 in the MS4A locus. The risk allele of rs636317 disrupts a CTCF binding motif, altering fine-scale chromatin looping. To validate these findings, we employed CRISPR/Cas9 to generate an allele-specific deletion of the rs636317 T allele in H9 human embryonic stem cells. Monocytes differentiated from these edited cells displayed increased expression of MS4A4E, MS4A6A, and TREM2, along with highly elevated levels of soluble TREM2 (sTREM2). These results provide a mechanistic link between a non-coding genetic variant, transcriptional regulation of the MS4A family, and TREM2-mediated immune responses in Alzheimers disease pathogenesis.

genetics↗

bioRxiv2025

Rare longevity-associated variants, including a reduced-function mutation in cGAS, identified in multigenerational long-lived families

Life expectancy has steadily increased in the last two centuries, while healthspan has been lagging behind. Survival into extreme ages strongly clusters within families which often exhibit a delayed onset of (multi)morbidity, yet the underlying protective genetic mechanisms are still largely undefined. We performed affected sib-pair linkage analysis in 212 sibships enriched for ancestral longevity and identified four genomic regions (LODmax [≥]3.0) at 1q21.1, 6p24.3, 6q14.3, and 19p13.3. Within these regions, we prioritized 12 rare protein-altering variants in seven candidate genes (NUP210L, SLC27A3, CD1A, CGAS, IBTK, RARS2, and SH2D3A) located in longevity-associated loci. Notably, a missense variant in CGAS (rs200818241), was present in two sibships. Using human- and mouse-based cell models, we showed that rs200818241 reduced protein stability and attenuated activation of the canonical cGAS-STING pathway in a cell-type specific manner. This dampened signalling mitigated inflammation and delayed cellular senescence, mechanisms that may contribute to the survival advantage of CGAS variant carriers. Our findings indicate novel rare variants and candidate genes linked to familial longevity and highlight the cGAS-STING pathway as a potential contributor to the protective mechanisms underlying human longevity.

genetics↗

bioRxiv2025

Rare centenarian SIRT6 coding variants elevate SIRT6 protein levels and resist cellular senescence

Centenarians provide valuable insights into the biological mechanisms underlying human longevity and potential gerotherapeutic targets. We previously identified two linked missense variants in SIRT6 that are enriched in Ashkenazi Jewish centenarians. To investigate their functional impact in physiologically relevant cellular contexts, we generated human embryonic stem cells carrying these variants through precise genomic knock-in and differentiated them into somatic lineages. Functional characterization revealed that the centenarian variants endogenously elevated SIRT6 protein levels through weakened interaction with vimentin, and altered SIRT6 enzymatic activities including enhanced mono-ADP-ribosyl transferase activity and reduced deacetylase activity. These variants delayed replicative and progerin-induced cellular senescence, preserving genome stability through maintenance of DNA repair pathways and suppression of transposable element derepression. Moreover, pharmacologically mimicking the centenarian variants using SIRT6 activator Fucoidan-FV partially ameliorated premature aging-associated molecular defects in progeria fibroblasts. Together, our findings demonstrate that rare centenarian variants exert multifaceted effects on SIRT6 and enhance cellular resilience, providing insights for developing geroprotective therapies informed by genetic discoveries in exceptionally long-lived individuals.

cell biology↗

bioRxiv2025

Epigenetic CRISPR Screening of 9p21.3 Non-Coding Regions identifies Cis-Regulatory Elements of P16INK4a and P15INK4b Controlling Cellular Senescence

Cellular senescence is a hallmark of aging and a promising target for extending human healthspan. Senescence is often accompanied by upregulation of the key senescence marker gene CDKN2A, yet the mechanism underlying its transcriptional activation remains unclear due to complex cis-regulations within the 9p21.3 locus. Here, we performed complementary CRISPR activation and interference screens in human mesenchymal stromal cells (MSCs) to systematically map non-coding cis-regulatory elements (CREs) at this locus that epigenetically regulate senescence. This approach revealed senescence-regulating CREs (SenReg-CREs) that bidirectionally modulate senescence through P16INK4a and P15INK4b. Notably, we identified a primate-specific short interspersed nuclear element (SINE) MIR3 embedded within the most potent distal SenReg-CRE. Deletion of this SINE:MIR3 accelerated senescence, revealing its potential insulator function in restraining CDKN2A/CDKN2B activation. Collectively, these findings reveal novel mechanisms underlying senescence-associated transcriptional activation of CDKN2A/CDKN2B and demonstrate that senescence is malleable through manipulation of regulatory element activity, highlighting the potential of epigenetically targeting these SenReg-CREs for senomorphic interventions.

genomics↗

bioRxiv2025

Single-cell transcriptomics showed that maternal PCB exposure dysregulated ER stress-mediated cell type-specific responses in the liver of female offspring

Polychlorinated biphenyls (PCBs) are persistent environmental toxicants that bioaccumulate in the food chain and readily cross the placenta, raising concerns for developmental toxicity. While PCB exposure has been associated with metabolic and neurodevelopmental disorders, its cell type-specific effects on liver development remain poorly understood. This study aimed to investigate how maternal exposure to an environmentally relevant Fox River PCB mixture affects liver development in female offspring at single-cell resolution. We hypothesized that early-life PCB exposure disrupts hepatic metabolic and immune function in a cell type-specific manner. Using single-cell RNA sequencing (scRNA-seq) on liver tissue from postnatal day 28 female mice perinatally exposed to PCBs, we identified major hepatic and immune cell populations and assessed cell-specific transcriptional responses. PCB exposure significantly altered the proportions of endothelial cells and Kupffer cells and reduced neutrophil abundance. Transcriptomic analysis revealed that PCBs dysregulated key pathways in hepatocytes and non-parenchymal cells, including ER stress responses, drug metabolism, and glucose/insulin signaling. Notably, hepatocytes exhibited upregulation of phase-I drug-metabolizing enzymes and uptake transporters, but downregulation of phase-II enzymes and efflux transporters. Kupffer cells and endothelial cells had altered immune and metabolic gene expression, and intercellular communication analysis predicted disrupted fibronectin, collagen, and chemokine signaling due to PCB exposure. RT-qPCR validation confirmed increased hepatic ER stress marker expression. Together these findings demonstrate that perinatal PCB exposure induces persistent, cell type-specific transcriptomic reprogramming in the liver, impairing metabolic and immune functions. This study highlights the utility of single-cell transcriptomics for revealing toxicant effects with cellular precision during critical windows of development.

systems biology↗

bioRxiv2025

Uncovering the Signatures of Cellular Senescence in the Human Dorsolateral Prefrontal Cortex

Identifying senescent cells poses challenges due to their rarity, heterogeneity, and lack of a definitive marker. We performed Visium spatial transcriptomics (ST) and single nucleus RNA sequencing (snRNA-seq) on non-pathological human tissue to build a transcriptomic atlas of aging and senescence in the dorsolateral prefrontal cortex (dlPFC). We identified markers characteristic of aging dlPFC cortical layers and cell types. We also observed an increase in astrocyte abundance and decrease in somatostatin expressing inhibitory neurons. Overall, the senescence profile in the dlPFC was highly heterogeneous and heavily influenced by cell type identity and cortical layer. Combined unbiased analysis of ST and snRNA-seq datasets revealed gene expression modules encoding for communities of microglia and endothelial cells in the white matter and regional astrocytes programs that were strongly enriched with age and for senescence-related genes. These findings will help facilitate future studies exploring the function of senescent cell subpopulations in the aging brain.

cell biology↗

bioRxiv2024

Transcriptomic signatures of mouse ovarian aging and estropausal transition at single cell resolution

Female reproductive aging affects fertility and overall health. Functional decline in mouse ovary during reproductive aging is accompanied by estrous cycle prolongation and cessation. However, the molecular mechanism underlying reproductive aging concomitant with such cycle changes remains unclear. Using single-cell transcriptomics, we characterized aging signatures in mouse ovaries across the reproductive lifespan ranging from reproductively young (regular cycle) through peri-estropause (regular vs. irregular cycles) to post-estropause age (acyclic). Reproductive aging significantly remodeled cell compositions and increased transcriptional heterogeneity, with more pronounced changes post-estropause, exhibiting coordinated alterations across cell types in the ovary. Genes undergoing monotonic changes during reproductive aging across cell types were consistently enriched in the conserved pathways of aging, including oxidative phosphorylation, stress responses, and proteostasis. Additionally, cell type-specific changes were identified including dysregulation of hormone synthesis in granulosa cells, alterations in collagen and hyaluronan metabolism in stromal and early theca cells, and functional decline of a unique phagocytosis-associated macrophage. Aging also led to a significant decrease in cell-cell communications, particularly between stromal and granulosa cells, and an increase in extracellular vesicle secretion. Furthermore, we found increased expression of the senescence marker Cdkn1a and senescence-associated secretory phenotype (SASP) factors during ovarian aging, especially in granulosa cells. Notably, most of these aging-associated changes were more pronounced in irregular cycling ovaries compared to the regular cycling counterparts at the same age during the peri-estropause stage, suggesting that aging-related molecular changes in the ovary drive the estropausal transition in mice.

bioinformatics↗

bioRxiv2024

Recruitment of CTCF to the SIRT1 promoter after Oxidative Stress mediates Cardioprotective Transcription

Because most DNA-binding transcription factors (dbTFs), including the architectural regulator CTCF, bind RNA and exhibit di-/multimerization, a central conundrum is whether these distinct properties are regulated post-transcriptionally to modulate transcriptional programs. Here, investigating stress-dependent activation of SIRT1, encoding an evolutionarily-conserved protein deacetylase, we show that induced phosphorylation of CTCF acts as a rheostat to permit CTCF occupancy of low-affinity promoter DNA sites to precisely the levels necessary. This CTCF recruitment to the SIRT1 promoter is eliciting a cardioprotective cardiomyocyte transcriptional activation program and provides resilience against the stress of the beating heart in vivo. Mice harboring a mutation in the conserved low-affinity CTCF promoter binding site exhibit an altered, cardiomyocyte-specific transcriptional program and a systolic heart failure phenotype. This transcriptional role for CTCF reveals that a covalent dbTF modification regulating signal-dependent transcription serves as a previously unsuspected component of the oxidative stress response.

cell biology↗

bioRxiv2024

Two retrotransposon-derived capsid genes PNMA1 and PNMA4 maintain reproductive capacity

The human genome contains 24 gag-like capsid genes derived from deactivated retrotransposons conserved among eutherians. Although some of their encoded proteins retain the ability to form capsids and even transfer cargo, their fitness benefit has remained elusive. Here we show that the gag-like genes PNMA1 and PNMA4 support reproductive capacity. Six-week-old mice lacking either Pnma1 or Pnma4 are indistinguishable from wild-type littermates, but by six months the mutant mice become prematurely subfertile, with precipitous drops in sex hormone levels, gonadal atrophy, and abdominal obesity; overall they produce markedly fewer offspring than controls. Analysis of donated human ovaries shows that expression of both genes declines normally with aging, while several PNMA1 and PNMA4 variants identified in genome-wide association studies are causally associated with low testosterone, altered puberty onset, or obesity. These findings expand our understanding of factors that maintain human reproductive health and lend insight into the domestication of retrotransposon-derived genes.

genetics↗

bioRxiv2024

In vitro heterochronic parabiosis identifies pigment epithelium-derived factor as a systemic mediator of rejuvenation by young blood

Several decades of heterochronic parabiosis (HCPB) studies have demonstrated the restorative impact of young blood, and deleterious influence of aged blood, on physiological function and homeostasis across tissues, although few of the factors responsible for these observations have been identified. Here we develop an in vitro HCPB system to identify these circulating factors, using replicative lifespan (RLS) of primary human fibroblasts as an endpoint of cellular health. We find that RLS is inversely correlated with serum donor age and sensitive to the presence or absence of specific serum components. Through in vitro HCPB, we identify the secreted protein pigment epithelium-derived factor (PEDF) as a circulating factor that extends RLS of primary human fibroblasts and declines with age in mammals. Systemic administration of PEDF to aged mice reverses age-related functional decline and pathology across several tissues, improving cognitive function and reducing hepatic fibrosis and renal lipid accumulation. Together, our data supports PEDF as a systemic mediator of the effect of young blood on organismal health and homeostasis and establishes our in vitro HCPB system as a valuable screening platform for the identification of candidate circulating factors involved in aging and rejuvenation.

cell biology↗

bioRxiv2023

A Computational Approach for the Identification of Novel L1 Transcriptional Regulators

Long interspersed element 1 (L1) are a family of autonomous, actively mobile transposons that occupy [~]17% of the human genome. A number of pleiotropic effects induced by L1 (promoting genome instability, inflammation, or cellular senescence) have been observed, and L1s contributions to aging and aging diseases is an area of active research. However, because of the cell type-specific nature of transposon control, the catalogue of L1 regulators remains incomplete. Here, we employ an eQTL approach leveraging transcriptomic and genomic data from the GEUVADIS and 1000Genomes projects to computationally identify new candidate regulators of L1 RNA levels in lymphoblastoid cell lines. To cement the role of candidate genes in L1 regulation, we experimentally modulate the levels of top candidates in vitro, including IL16, STARD5, HSDB17B12, and RNF5, and assess changes in TE family expression by Gene Set Enrichment Analysis (GSEA). Remarkably, we observe subtle but widespread upregulation of TE family expression following IL16 and STARD5 overexpression. Moreover, a short-term 24-hour exposure to recombinant human IL16 was sufficient to transiently induce subtle, but widespread, upregulation of L1 subfamilies. Finally, we find that many L1 expression-associated genetic variants are co-associated with aging traits across genome-wide association study databases. Our results expand the catalogue of genes implicated in L1 RNA control and further suggest that L1-derived RNA contributes to aging processes. Given the ever-increasing availability of paired genomic and transcriptomic data, we anticipate this new approach to be a starting point for more comprehensive computational scans for transposon transcriptional regulators.

bioinformatics↗

bioRxiv2023

Identification and functional validation of an enhancer variant in the 9p21.3 locus associated with glaucoma risk and elevated expression of p16INK4a

Glaucoma is a leading cause of irreversible blindness, with advanced age being the single most significant risk factor. However, the mechanisms underlying the relationship between aging and glaucoma remain unclear. Genome-wide association studies (GWAS) have successfully identified genetic variants strongly associated with increased glaucoma risk. Understanding how these variants function in pathogenesis is crucial for translating genetic associations into molecular mechanisms and, ultimately, clinical applications. The chromosome 9p21.3 locus is among the most replicated glaucoma risk loci discovered by GWAS. Nonetheless, the absence of protein-coding genes in the locus makes interpreting the disease association challenging, leaving the causal variant and molecular mechanism elusive. In this study, we report the identification of a functional glaucoma risk variant, rs6475604. By employing computational and experimental methods, we demonstrated that rs6475604 resides in a repressive regulatory element. Risk allele of rs6475604 disrupts the binding of YY1, a transcription factor known to repress the expression of a neighboring gene in 9p21.3, p16INK4A, which plays a crucial role in cellular senescence and aging. These findings suggest that the glaucoma disease variant contributes to accelerated senescence, providing a molecular link between glaucoma risk and an essential cellular mechanism for human aging.

genetics↗

bioRxiv2023

The regulation of Insulin/IGF-1 signaling by miR-142-3p associated with human longevity

MicroRNAs (miRNAs) have been demonstrated to modulate life span in the invertebrates C. elegans and Drosophila by targeting conserved pathways of aging, such as insulin/IGF-1 signaling (IIS). However, a role for miRNAs in modulating human longevity has not been fully explored. Here we investigated novel roles of miRNAs as a major epigenetic component of exceptional longevity in humans. By profiling the miRNAs in B-cells from Ashkenazi Jewish centenarians and 70-year-old controls without a longevity history, we found that the majority of differentially expressed miRNAs were upregulated in centenarians and predicted to modulate the IIS pathway. Notably, decreased IIS activity was found in B cells from centenarians who harbored these upregulated miRNAs. miR-142-3p, the top upregulated miRNA, was verified to dampen the IIS pathway by targeting multiple genes including GNB2, AKT1S1, RHEB and FURIN. Overexpression of miR-142-3p improved the stress resistance under genotoxicity and induced the impairment of cell cycle progression in IMR90 cells. Furthermore, mice injected with a miR-142-3p mimic showed reduced IIS signaling and improved longevity-associated phenotypes including enhanced stress resistance, improved diet/aging-induced glucose intolerance, and longevity-associated change of metabolic profile. These data suggest that miR-142-3p is involved in human longevity through regulating IIS-mediated pro-longevity effects. This study provides strong support for the use of miR-142-3p as a novel therapeutic to promote longevity or prevent aging/aging-related diseases in human.

molecular biology↗

bioRxiv2023

Longevity-associated SMAD3 non-coding centenarian variant impairs a cell-type specific enhancer to reduce inflammation

Given the pro and anti-geronic roles of the TGF-{beta} superfamily in aging, we hypothesized that human longevity involves genetic variation in TGF-{beta} signaling genes. Here we utilized a candidate functional genomic approach to identify and characterize functional variants in TGF- {beta} signaling associated with human longevity. Targeted sequencing of 113 genes involved in aging- associated TGF- {beta} signaling in an Ashkenazi Jewish centenarian cohort identified genetic variants robustly associated with human longevity. In particular, a centenarian-enriched intronic variant residing in a cell-type specific enhancer in SMAD3, a critical receptor-regulated TGF- {beta} signal transducer, was identified. This non-coding SMAD3 variant (rs8040709) altered binding of ELK1, a member of the ETS family of transcription factor important for enhancer activity in certain cell types, resulting in reduced SMAD3 expression. Analysis of the variant in cell types derived from gene edited iPSCs demonstrated the variant reduced SMAD3 expression, senescence and inflammation in endothelial cells. In addition, heterozygosity in SMAD3 improved healthspan and reduced senescence in the Ercc1-/{Delta} progeroid mouse model of accelerated aging. Taken together, these experiments demonstrate that variants in a cell type specific enhancer of SMAD3 resulted in reduced expression, senescence and inflammation and contributes to human longevity. Thus, SMAD3 represents a validated targeted for drug development for extending human healthspan.

genetics↗

bioRxiv2022

Decoding the Variant-to-Function Relationship for LIPA, a Risk Locus for CAD

Translating human genomic discoveries into mechanistic insights requires linking genetic variations to candidate genes and their causal functional phenotypes. Genome-wide association studies have consistently identified LIPA as a risk locus for coronary artery disease (CAD), with previous expression quantitative trait loci (eQTL) analyses prioritizing LIPA as a candidate causal gene. However, functional studies elucidating the causal variants, regulatory mechanisms, target cell types, and their causal impact on atherosclerosis have been lacking. To address this gap, we applied functional genomics and experimental mouse models to establish the variant-to-function relationship at the LIPA locus. Our findings show that CAD risk alleles in the LIPA locus increase LIPA expression and enzyme activity specifically in monocytes/macrophages by enhancing PU.1 binding to an intronic enhancer region that interacts with the LIPA promoter. In myeloid Lipa-overexpressing mice, we observed larger atherosclerotic lesions accompanied by altered macrophage function, including increased macrophage accumulation due to enhanced monocyte recruitment, reduced neutral lipid accumulation, and upregulation of integrin and extracellular matrix pathways. Our work establishes a direct causal link between LIPA risk alleles and increased monocyte/macrophage LIPA that exacerbates atherosclerosis, bridging human functional genomic evidence to the mechanistic understanding of CAD. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=58 SRC="FIGDIR/small/516293v2_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@11ce287org.highwire.dtl.DTLVardef@15c201aorg.highwire.dtl.DTLVardef@13f90c9org.highwire.dtl.DTLVardef@3aa3be_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

bioRxiv2022

A systems biology-based identification and in vivo functional screening of Alzheimer's disease risk genes reveals modulators of memory function

Genome-wide association studies (GWAS) have uncovered over 40 genomic loci associated with risk for late-onset Alzheimers Disease (LOAD), but identification of the underlying causal genes remains challenging. While the role of glial biology in the mediation of LOAD genetic risk has been increasingly recognized, recent studies of induced pluripotent stem cell (iPSC)-derived neurons from LOAD patients have demonstrated the existence of neuronal cell-intrinsic functional defects, absent interactions with other brain cell types or exposure to neurotoxic insults. Here, we searched for genetic contributions to neuronal dysfunction in LOAD pathobiology, using an integrative systems approach that incorporated multi-evidence-based gene-mapping and network analysis-based prioritization. We found widespread dysfunction in neuronal gene co-expression networks in the LOAD brain and identified synaptic and endolysosomal function as being specifically impacted by LOAD-associated genetic variation. A systematic perturbation screening of candidate risk genes in C. elegans revealed that neuronal knockdown of the LOAD risk gene orthologs vha-10 (ATP6V1G2), cmd-1 (CALM3), amph-1 (BIN1), ephx-1 (NGEF), and pho-5 (ACP2) significantly alters short/intermediate-term memory function, the cognitive domain affected earliest during LOAD progression. These results highlight the impact of LOAD risk genes on evolutionarily conserved memory function, as mediated through neuronal endosomal dysfunction, and identify new targets for further mechanistic interrogation.

genetics↗