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Wang, J. J.

Publications and source records attributed to Wang, J. J..

13 recordsLinked to original sources

ThermoClock: A Novel Automated Temperature Regulation Device that Can Model Circadian Entrainment and Disruption in 2D and 3D in Vitro Models

Circadian rhythms are critical for maintaining homeostasis and regulating physiological functions, and consequentially impact disease progression; yet, they remain largely overlooked in in vitro models used in preclinical research. One major barrier to rigorously testing the role of circadian rhythms in these models is the lack of accessible tools that seamlessly integrate into standard culture setups and are capable of sustainably delivering time cues to cells and tissues in long term experiments. Here, we present the ThermoClock, a low-cost, Arduino-based automated temperature control system capable of delivering independent temperature programs to multiple cultures simultaneously. Using circadian reporter U2OS cell lines (Bmal1:Luc and Per2:Luc), we demonstrated that ThermoClock-driven temperature cycles (36{degrees}C/38.5{degrees}C, 12h:12h) produced significantly higher amplitude entrainment than a programmable incubator delivering identical temperature trajectories, suggesting that the ramp time to setpoint is a critical determinant of entrainment strength. We further applied ThermoClock to skin explants from keratinocyte-specific Dbp:Luc reporter mice, showing that circadian temperature cycles (T24: 12h:12h and T25: 12.5h:12.5h) extended synchronized circadian rhythms ex vivo, while a shortened T-cycle (T20: 10h:10h) induced rhythm disruptions. We also observed reduced cell migration in T20 temperature-entrained explants wounded ex vivo, closely recapitulating attenuated wound healing observed in T20 light-cycle-disrupted mice in vivo. Finally, we show that wounding can act as a phase-resetting cue but its efficacy depends on pre-injury entrainment state, with circadian entrained tissues (T25) resisting reset, while disrupted (T20) and unentrained tissues showed resetting sensitivity. These findings establish ThermoClock as a versatile platform for incorporating circadian regulation and, for the first time, disruption into 2D and 3D in vitro systems and demonstrate that peripheral clock disruption and its functional consequences can be modeled ex vivo.

bioengineering↗

Multi-omics integration of malignant peripheral nerve sheath tumors identifies potential targets based on chromosome 8q status

BackgroundChromosome 8q (chr8q) copy number gain is associated with high-grade transformation in malignant peripheral nerve sheath tumors (MPNST), an aggressive soft tissue tumor with poor outcomes in the high-risk and metastatic settings. Although chr8q gain is associated with inferior overall survival in patients with MPNST, standard of care therapies do not currently consider stratification by genomic features, including chr8q status. MethodsWe employed a proteogenomic approach to characterize proteomic and transcriptional programs associated with chr8q and nominate drug targets for potential treatment stratification based on chr8q status. We leveraged our growing library of fully characterized MPNST patient-derived xenografts (PDX) and collected LC-MS/MS global and phospho-proteomics measurements for six of these samples. We then integrated these data with transcriptomics and copy number data to identify molecular changes that are correlated with chr8q copy number. We nominated pathways, transcription factors, and kinases that were differentially active in chr8q gain samples and posited that these samples would respond differently to drugs compared to chr8q wildtype samples. We then tested this hypothesis in vitro. ResultsOur results suggest that the chr8q gene MYC may be a key driver of downstream effects that can be targetable with inhibitors of PLK1. Conversely, EGFR inhibition may be more effective in MYC-diploid MPNSTs than those with MYC gain. These results nominate candidate pathways and drug classes to target tumor heterogeneity in MPNST through the proteogenomic integration and drug sensitivity prediction in distinct tumor subpopulations. ConclusionsWe show that integration of multiomics data can identify specific drug therapies to selectively target tumor cells based on chr8q copy number. This not only provides novel avenues for drug nomination going forward but also may be important for stratifying treatment and mitigating resistance in heterogeneous tumors.

cancer biology↗

Adrenergic Hypersensitivity Drives Ventricular Arrhythmias Following Loss of Plexin-Mediated Cardiac Innervation

BackgroundVentricular arrhythmias (VAs) are a leading cause of death and arise from a combination of cardiac muscle injury and dysfunction of the intramyocardial sympathetic nerves that control cardiac electrophysiology. The adrenergic mechanisms by which intramyocardial nerves contribute to arrhythmogenesis are poorly understood. Semaphorin-plexin signaling pathways are responsible for developmental guidance of sympathetic nerves onto the heart and have previously been associated with VAs in humans. ObjectiveTo investigate adrenergic control of arrhythmogenesis, we probed the cardiac electrophysiology of a Plexin-A3/-A4 double knockout mouse with loss of cardiac adrenergic nerves. MethodsWe studied cardiac structure and function using tissue clearing, immunohistochemistry, and echocardiography. We utilized ECG and optical mapping of action potentials to evaluate electrophysiologic responses to pharmacologic beta ({beta})-adrenergic stimulation and blockade. We measured circulating catecholamines and quantified {beta}-adrenergic receptor ({beta}AR) density in cardiac membranes. Finally, we performed a phenome-wide association study utilizing data from the UK Biobank to search for associations between PLXNA4 and human arrhythmias. ResultsMice with loss of plexin-dependent cardiac innervation had structurally normal hearts but displayed spontaneous VAs driven by adrenergic hypersensitivity, as well as increased cardiac {beta}AR density. Several human PLXNA4 variants were associated with arrhythmia phenotypes. ConclusionThese data establish a model of VAs driven by enhanced adrenergic receptor signaling, in the absence of structural heart disease, which can be used to investigate adrenergic mechanisms of arrhythmogenesis and to identify novel antiarrhythmic targets.

physiology↗

Molecular mechanisms of uric acid transport by the native human URAT1 and its inhibition by anti-gout drugs

Gout, a common and painful disease, stems from hyperuricemia, where elevated blood uric acid levels lead to urate crystal formation in joints and kidneys. The human urate transporter 1 (hURAT1) plays a critical role in urate homeostasis by facilitating urate reabsorption in the renal proximal tubule, making it a key target for gout therapy. Pharmacological inhibition of hURAT1 with drugs such as dotinurad, benzbromarone, lesinurad, and verinurad promotes uric acid excretion and alleviates gout symptoms. Here we present cryo-electron microscopy structures of native hURAT1 bound with these anti-gout drugs in the inward-open state, and with uric acid in inward-open, outward-open, and occluded states. Complemented by mutagenesis and cell-based assays, these structures reveal the mechanisms of uric acid reabsorption and hURAT1 inhibition. Our findings elucidate the molecular basis of uric acid transport and anti-gout medication action, and provide a structural framework for the rational design of next-generation therapies for hyperuricemia and gout.

biochemistry↗

The gut microbiota is essential for Trichinella spiralis-evoked suppression of colitis

Inflammatory bowel disease (IBD) increases the risk of colorectal cancer, and it has the potential to diminish the quality of life. Clinical and experimental evidence demonstrate protective aspects of parasitic helminth infection against IBD. However, studies on the inhibition of inflammation by helminth infection have overlooked a key determinant of health: the gut microbiota. Infection with helminths induces alterations in the host microbiota composition. However, the potential influence and mechanism of helminth infections induced changes in the gut microbiota on the development of IBD has not yet been elucidated. In this study, we analyzed the intersection of helminth Trichinella spiralis and gut bacteria in the regulation of colitis and related mechanisms. T. spiralis infected mice were treated with antibiotics or cohused with wild type mice, then challenged with DSS-colitis and disease severity, immune responses and goblet cells assessed. Gut bacteria composition was assessed by 16 s rRNA sequencing and SCFAs were measured. Results showed that protection against disease by infection with T. spiralis was abrogated by antibiotic treatment, and cohousing with T. spiralis- infected mice suppressed DSS-colitis in wild type mice. Bacterial community profiling revealed an increase in the abundance of the bacterial genus Muribaculum and unclassified_Muribaculaceae in mice with T. spiralis infection or mice cohoused with T. spiralis- infected mice. Metabolomic analysis demonstrated increased propionic acid in feces from T. spiralis- infected mice. Data also showed that the gut microbiome modulated by T. spiralis exhibited enhanced goblet cell differentiation and elevated IL-10 levels in mice. Taken together, these findings identify the gut microbiome as a critical component of the anti-colitic effect of T. spiralis and gives beneficial insights into the processes by which helminth alleviates colitis. Author SummaryInflammatory bowel disease (IBD) encompasses Crohns Disease and Ulcerative Colitis. It affects both children and adults. Reports have highlighted the potential use of helminths or their byproducts as a possible treatment for IBD. Accumulating evidence also suggests that the gut microbiota is a key factor in modulating IBD. In this study, we revealed the protective effect of a prior infection with T. spiralis on DSS-induced colitis in mice. Specifically, T. spiralis infection reshaped the gut microbiome of mice, resulting in an increased abundance of SCFA-producing bacteria Muribaculum and unclassified_Muribaculaceae and thereby producing a larger amount of propionic acid. Furthermore, the gut microbiome modulated by T. spiralis exhibited enhanced goblet cell differentiation and elevated IL-10 levels, ultimately ameliorating experimental colitis. These findings suggest that the modulation of host microbiota during T. spiralis infection plays a crucial role in the suppression of colitis, and any intention-to-treat with helminth therapy should be based on the patients immunological and microbiological response to the helminth.

microbiology↗

Bioorthogonal labeling and enrichment of histone monoaminylation reveal its accumulation and regulatory function in cancer cell chromatin

Histone monoaminylation (i.e., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/586010v3_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@1bee3f7org.highwire.dtl.DTLVardef@1687013org.highwire.dtl.DTLVardef@1960bd0org.highwire.dtl.DTLVardef@1e19a04_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

Self-reactive B cells traverse a perfect storm of somatic mutagenesis to cause a virus-induced autoimmune disease

The unexplained association between infection and autoimmune disease is strongest for hepatitis C virus-induced cryoglobulinemic vasculitis (HCV-CV). We traced the evolution of the pathogenic rheumatoid factor (RhF) autoantibodies in four HCV-CV patients by deep single cell multi-omic analysis, revealing three sources of B cell somatic mutation converged to drive accumulation of a large disease causing clone. A sensitive method for quantifying low affinity binding revealed three recurring heavy/light chain combinations created by V(D)J recombination bound self IgG but not viral E2 antigen. Whole genome sequencing revealed accumulation of thousands of somatic mutations, at levels comparable to CLL and normal memory B cells, but with 1-2 corresponding to driver mutations found recurrently in B cell leukemia/lymphoma. V(D)J hypermutation created autoantibodies with compromised solubility. In this virus-induced autoimmune disease, infection promotes a perfect storm of somatic mutagenesis in the descendants of a single B cell.

immunology↗

SIX4 Controls STING Expression Enhancing anti-PD-1 Efficacy

The cGAS/STING cytosolic DNA sensing pathway plays a central role in anti-tumor immunity. Expression of STING is tightly regulated and commonly reduced or defective in many types of cancer. We have identified SIX4 as a significant regulator of STING expression in colon cancer cells. We showed that knockout of SIX4 decreased STING expression at the mRNA and protein levels while ectopic expression of SIX4 increased STING expression. Depletion of SIX4 led to attenuated STING activation and downstream signaling. Re-expression of SIX4 or ectopic expression of STING in SIX4 knockout cells reversed the effect. Ectopic expression of SIX4 enhanced DMXAA and cGAMP-induced STING activation and downstream signaling. Importantly, decrease of SIX4 expression substantially decreased tumor infiltration of CD8+ T-cells and reduced the efficacy of PD-1 antibodies to diminish tumor growth in immune competent mice in vivo. Finally, analysis of TCGA colon cancer dataset indicated that tumors with high SIX4 expression were significantly enriched in the Inflammatory Response pathway. SIX4 expression also correlated with expression of multiple IFN-stimulated genes, inflammatory cytokines and CD8A. Taken together, our results implicate that SIX4 is a principal regulator of STING expression in colon cancer cells, providing an additional mechanism and genetic marker to predict effective immune checkpoint blockade therapy responses.

cancer biology↗

The protein folding rate and the geometry and topology of the native state

Proteins fold in 3-dimensional conformations which are important for their function. Characterizing the global conformation of proteins rigorously and separating secondary structure effects from topological effects is a challenge. New developments in Applied Knot Theory allow to characterize the topological characteristics of proteins (knotted or not). By analyzing a small set of two-state and multi-state proteins with no knots or slipknots, our results show that 95.4% of the analyzed proteins have non-trivial topological characteristics, as reflected by the second Vassiliev measure, and that the logarithm of the experimental protein folding rate depends on both the local geometry and the topology of the proteins native state.

bioinformatics↗

CASCADES, a novel SOX2 super-enhancer associated long noncoding RNA, regulates cancer stem cell specification and differentiation in glioblastoma multiforme

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults, with a median survival of just over one year. The failure of available treatments to achieve remission in patients with GBM has been attributed to the presence of cancer stem cells (CSCs), which are thought to play a central role in tumor development and progression and serve as a treatment-resistant cell repository capable of driving tumor recurrence; in fact, the property of "stemness" itself may be responsible for treatment resistance. In this study, we identify a novel lncRNA, Cancer stem cell associated distal enhancer of SOX2 (CASCADES) that functions as an epigenetic regulator in glioma CSCs (GSCs). CASCADES is expressed in IDH-wild type GBM and significantly enriched in GSCs. Knockdown of CASCADES in GSCs results in differentiation towards a neuronal lineage in a cell- and cancer-specific manner. Bioinformatics analysis reveals that CASCADES functions as a super-enhancer associated lncRNA epigenetic regulator of SOX2. Our findings identify CASCADES as a critical regulator of stemness in GSCs and represent a novel epigenetic and therapeutic target for disrupting the cancer stem cell compartment in GBM.

cancer biology↗

Genomic Epidemiology of Escherichia coli Isolates from a Tertiary Referral Center in Lilongwe, Malawi

Antimicrobial resistance (AMR) is a global threat, including in sub-Saharan Africa. However, little is known about the genetics of resistant bacteria in the region. In Malawi, there is growing concern about increasing rates of antimicrobial resistance to most empirically used antimicrobials. The highly drug resistant Escherichia coli sequence type (ST) 131, which is associated with the extended spectrum {beta}-lactamase blaCTX-M-15, has been increasing in prevalence globally. Previous data from isolates collected between 2006-2013 in southern Malawi have shown the presence of ST131 and the blaCTX-M-15 gene in the country. We performed whole genome sequencing (WGS) of 58 clinical E. coli isolates at Kamuzu Central Hospital, a tertiary care center in central Malawi, collected from 2012-2018. We used Oxford Nanopore Technologies (ONT) sequencing, which was performed in Malawi. We show that ST131 has become more prevalent (14.9% increasing to 32.8%) and that the blaCTX-M-15gene is occurring at a higher frequency (21.3% increasing to 44.8%). Phylogenetics show isolates are highly related between the central and southern geographic regions and confirm that ST131 isolates are contained in a single group consistent with recent expansion. All AMR genes, including blaCTX-M-15, were widely distributed across sequence types. We also identified an increased number of ST410 isolates, which in this study tend to carry a plasmid-located copy of blaCTX-M-15 gene at a higher frequency than blaCTX-M-15 occurs in ST131. This study confirms the expanding nature of ST131 and the wide distribution of the blaCTX-M-15 gene in Malawi. We also highlight the feasibility of conducting longitudinal genomic epidemiology studies of important bacteria with the sequencing done on site using a nanopore platform that requires minimal infrastructure. DATA SUMMARYThe sequencing data used for this analysis is available in public data repositories. Information on the sequences used is provided in Supplementary Table 2.

genetics↗

Unigene-based RNA-seq provides insights on drought stress responses in Marsdenia tenacissima

Marsdenia tenacissima is a well-known anti-cancer medicinal plant used in traditional Chinese medicine. Drought severely affects production and no information on its transcriptional responses to drought stress is available. In this study, cDNA libraries on control (CK), drought stress (T1), and re-watering (T2) treatments were constructed and HiSeq 2000 sequencing was performed using the Illumina platform. There were 43,129,228, 47,116,844, and 42,815,454 clean reads with Q20 values of 98.06, 98.04, and 97.88, respectively. A total of 8672, 6043, and 6537 differentially expressed genes (DEGs) were identified when CK vs. T1, CK vs. T2, and T1 vs. T2, respectively, were analyzed. In addition, 1039, 1016, and 980 transcription factors (TFs) were identified in CK, T1, and T2, respectively. Among them, 363, 267, and 299 TFs were identified as DEGs in CK vs. T1, CK vs. T2, and T1 vs. T2, respectively. These differentially expressed TFs mainly belonged to the bHLH, bZIP, C2H2, ERF, MYB, MYB-related, and NAC families. A comparative analysis of CK vs. T1 and T1 vs. T2 found that 1174 genes were up-regulated and 2344 were down-regulated under drought stress and this pattern was the opposite to that found after re-watering. Among the 1174 genes up-regulated by drought stress, 64 were homologous to known functional genes that directly protect plants against drought stress. Furthermore, 44 protein kinases and 38 TFs with opposite expression patterns under drought stress and re-watering were identified, which are possibly candidate regulators for drought stress resistance in M. tenacissima. Our study is the first to characterize the M. tenacissima transcriptome in response to drought stress, and will serve as a useful resource for future studies on the functions of candidate protein kinases and TFs involved in M. tenacissima drought stress resistance.

molecular biology↗

A personalized, multi-omics approach identifies genes involved in cardiac hypertrophy and heart failure

Identifying genes underlying complex diseases remains a major challenge. Biomarkers are typically identified by comparing average levels of gene expression in populations of healthy and diseased individuals. However, genetic diversities may undermine the effort to uncover genes with significant but individual contribution to the spectrum of disease phenotypes within a population. Here we leverage the Hybrid Mouse Diversity Panel (HMDP), a model system of 100+ genetically diverse strains of mice exhibiting different complex disease traits, to develop a personalized differential gene expression analysis that is able to identify disease-associated genes missed by traditional population-wide methods. The population-level and personalized approaches are compared for isoproterenol(ISO)-induced cardiac hypertrophy and heart failure using pre- and post-ISO gene expression and phenotypic data. The personalized approach identifies 36 Fold-Change (FC) genes predictive of the severity of cardiac hypertrophy, and enriched in genes previously associated with cardiac diseases in human. Strikingly, these genes are either up- or down-regulated at the individual strain level, and are therefore missed when averaging at the population level. Using insights from the gene regulatory network and protein-protein interactome, we identify Hes1 as a strong candidate FC gene. We validate its role by showing that even a mild knockdown of 20-40% of Hes1 can induce a dramatic reduction of hypertrophy by 80-90% in rat neonatal cardiac cells. These findings emphasize the importance of a personalized approach to identify causal genes underlying complex diseases as well as to develop personalized therapies.\n\nSignificanceA traditional approach to investigate the genetic basis of complex diseases is to look for genes with a global change in expression between diseased and healthy individuals. Here, we investigate individual changes of gene expression by inducing heart failure in 100 strains of genetically distinct mice. We find that genes associated to the severity of the disease are either up- or down-regulated across individuals and are therefore missed by a traditional population level approach. However, they are enriched in human cardiac disease genes and form a coregulated module strongly interacting with a cardiac hypertrophic signaling network in the human interactome. Our analysis demonstrates that individualized approaches are crucial to reveal all genes involved in the development of complex diseases.

systems biology↗