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Biology subjects

Suh, Y.

Publications and source records attributed to Suh, Y..

23 records · Page 2Linked to original sources

The regulatory landscapes of human ovarian ageing

Summary paragraphThe ovary is the first organ to age in the human body, affecting both fertility and overall health in women1-8. However, the biological mechanisms underlying human ovarian ageing remain poorly understood. Here we performed single-nuclei multi-omics analysis of young and reproductively aged human ovaries to understand the molecular and cellular basis of ovarian ageing in humans. Our analysis reveals coordinated changes in transcriptomic output and chromatin accessibility across cell types during ageing, including elevated mTOR and MAPK signaling, decreased activity of the oxidative phosphorylation and DNA damage repair pathways, and an increased signature of cellular senescence. By constructing cell type-specific regulatory networks, we uncover enhanced activity of the transcription factor CEBPD across cell types in the aged ovary, with a corresponding significant loss of activity of most cell identity-associated transcription factors. Moreover, by performing integrative analyses of our single-nuclei multi-omics data with common genetic variants associated with age at natural menopause (ANM) from genome-wide association studies, we demonstrate a global impact of functional variants on changes in gene regulatory networks across ovarian cell types. Finally, we nominate about a dozen of functional non-coding variants, their target genes and cell types and regulatory mechanisms that underlie genetic association with ANM. This work provides a comprehensive multimodal landscape of human ovarian ageing and mechanistic insights into inherited variation of ANM.

genomics↗

A rare human centenarian variant of SIRT6 enhances genome stability and interaction with Lamin A

Sirtuin 6 (SIRT6) is a deacylase and mono-ADP ribosyl transferase (mADPr) enzyme involved in multiple cellular pathways implicated in the regulation of aging and metabolism. Targeted sequencing identified a SIRT6 allele containing two linked substitutions (N308K/A313S) as enriched in Ashkenazi Jewish (AJ) centenarians as compared to AJ control individuals. Characterization of this SIRT6 (centSIRT6) allele demonstrated it to be a stronger suppressor of LINE1 retrotransposons, confer enhanced stimulation of DNA double strand break repair, and more robust cancer cell killing compared to the wild type. Surprisingly, centSIRT6 displayed weaker deacetylase activity, but stronger mADPr activity, over a range of NAD+ concentrations and substrates. Additionally, centSIRT6 displayed a stronger interaction with Lamin A/C (LMNA), which correlated with enhanced ribosylation of LMNA. Our results suggest that enhanced SIRT6 function contributes to human longevity by improving genome maintenance via increased mADPr activity and enhanced interaction with LMNA.

molecular biology↗

Transcriptome analysis reveals the difference between \"healthy\" and \"common\" aging and their connection with age-related diseases

A key goal of aging research is to understand mechanisms underlying healthy aging and use them to develop methods to promote the human healthspan. One approach is to identify gene regulations differentiating healthy aging from aging in the general population (i.e., \"common\" aging). In this study, we leveraged GTEx (Genotype-Tissue Expression) project data to investigate \"healthy\" and \"common\" aging in humans and their interconnection with diseases.\n\nWe selected GTEx donors who were not annotated with diseases to approximate a \"healthy\" aging cohort. We then compared the age-associated genes derived from this cohort with age-associated genes from our \"common\" aging cohort which included all GTEx donors; we also compared the \"healthy\" and \"common\" aging gene expressions with various disease-associated gene expression to elucidate the relationships among \"healthy\", \"common\" aging and disease. Our analyses showed that 1. \"healthy\" and \"common\" aging shared a large number of gene regulations; 2. Despite the substantial commonality, \"healthy\" and \"common\" aging genes also showed distinct function enrichment, and \"common\" aging genes had a higher enrichment for disease genes; 3. Disease-associated gene regulations were overall different from aging gene regulations. However, for genes regulated by both, their regulation directions were largely consistent, implying some aging processes could increase the susceptibility to disease development; and 4. Possible protective mechanisms were associated with the \"healthy\" aging gene regulations.\n\nIn summary, our work highlights several unique features of human \"healthy\" aging program. This new knowledge can be used for the development of therapeutics to promote human healthspan.

genetics↗

Tri-4C: efficient identification of cis-regulatory loops at hundred base pair resolution

The resolution limit of chromatin conformation capture methodologies (3Cs) has restrained their application in detection of fine-level chromatin structure mediated by cis-regulatory elements (CREs). Here we report two 3C-derived methods, Tri-4C and Tri-HiC, which utilize mult-restriction enzyme digestions for ultrafine mapping of targeted and genome-wide chromatin interaction, respectively, at up to one hundred basepair resolution. Tri-4C identified CRE loop interaction networks and quantifatively revealed their alterations underlying dynamic gene control. Tri-HiC uncovered global fine-gage regulatory interaction networks, identifying > 20-fold more enhancer:promoter (E:P) loops than in situ HiC. In addition to vasly improved identification of subkilobase-sized E:P loops, Tri-HiC also uncovered interaction stripes and contact domain insulation from promoters and enhancers, revealing their loop extrusion behaviors resembling the topologically-associated domain (TAD) boundaries. Tri-4C and Tri-HiC provide robust approaches to achieve the high resolution interactome maps required for characterizing fine-gage regulatory chromatin interactions in analysis of development, homeostasis and disease.

genetics↗

A novel approach of human geroprotector discovery by targeting the converging subnetworks of aging and age-related diseases

A key goal of geroscience research is to discover effective interventions to extend human healthspan, the years of healthy life. Currently, majority of the geroprotectors are found by testing compounds in model organisms; whether these compounds will be effective in humans is largely unknown. Here we present a novel strategy called ANDRU (aging network based drug discovery) to help the discovery of human geroprotectors. Instead of relying on model organisms, this approach is driven by human genomic and pharmacogenomic data. It first identifies human aging subnetworks that putatively function at the interface between aging and age-related diseases; it then screens for pharmacological or genetic interventions that may \"reverse\" the age-associated transcriptional changes seen in these subnetworks. We applied ANDRU to human adipose and artery tissues. In adipose tissue, PTPN1, a target for diabetes treatment and APOE, a known genetic factor for human longevity and diseases like Alzheimers disease, were ranked at the top. For small molecules, conjugated linoleic acid and metformin, a drug commonly used to treat type 2 diabetes, were ranked among the top compounds. In artery tissue, N-methyl-D-aspartate antagonists and curcumin were ranked at the top. In summary, ANDRU represents a promising human data-driven strategy that may speed up the discovery of interventions to extend human healthspan.

systems biology↗