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Yang, J. J.

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

At least 19 recordsLinked to original sources

Glucocorticoid receptor activation reorganizes Wnt/LEF1 regulatory circuitry associated with therapeutic response in B-cell acute lymphoblastic leukemia

Glucocorticoids (GCs) are foundational to B-cell acute lymphoblastic leukemia (B-ALL) therapy, yet how glucocorticoid receptor (GR) activation interacts with lineage regulatory circuitry to shape therapeutic response remains incompletely understood. Using LEF1 to interrogate canonical Wnt regulatory circuitry, we show that GR activation reorganizes GR+LEF1 elements into recruitment, retention, and dissociation states. LEF1 dissociates from Wnt-responsive regulatory elements while being recruited to GRE-rich GR-associated elements that progressively acquire chromatin accessibility, H3K27ac, BRD4 and BRG1. RUNX1 and AP-1 show class-dependent redistribution across LEF1-defined states, extending organization beyond LEF1. GR+LEF1 reorganization is observed in patient-derived B-ALL. GR+LEF1 elements lose accessibility in GC-resistant B-ALL and during diagnosis-to-relapse evolution, with recruitment elements enriched for remodeling. Perturbation of resistance-associated GR+LEF1 elements at BIM and BMF alters GC-induced apoptotic signaling. Together, these findings identify Wnt/LEF1 circuitry as an interface through which therapeutic GR activation reorganizes the B-ALL regulatory landscape into states associated with glucocorticoid response and resistance.

cancer biology↗

mRNA-LNP therapy restores systemic nucleoside imbalance in a mitochon-drial DNA depletion syndrome

Mitochondrial DNA depletion syndromes (MDS) are inherited conditions caused by pathogenic variants in mitochondrial DNA maintenance genes. Most MDS are severe, fatal and incurable conditions. Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an MDS resulting from loss-of-function mutations in the TYMP gene, encoding Thymidine Phosphorylase (TP). Systemic nucleoside accumulation caused by TP deficiency disrupts mitochondrial nucleotide homeostasis, which underlies disease progression and mortality. Current treatments, including liver and hematopoietic stem cell transplantation, partially restore TP activity but are invasive, carry substantial risk and are limited by donor availability. Here, we establish TYMP-mRNA in lipid nanoparticles (hTYMP-mRNA-LNPs) as a safe non-viral protein-replacement therapy for MNGIE. Intravenous administration of hTYMP-mRNA-LNPs induced robust hepatic TP expression in a mouse model of MNGIE, was well tolerated and restored circulating nucleosides to wild-type levels within hours, lasting up to three weeks, at a preclinical minimally effective dose of 0.25mg/kg. To facilitate repeat administration and patient access, we demonstrate enhanced efficiency of subcutaneous mRNA-LNP delivery by co-administration of recombinant or mRNA-encoded (SPAM1-mRNA-LNPs) hyaluronidase, achieving effective hepatic TP expression and systemic nucleoside clearance. These findings establish mRNA-LNP-mediated protein replacement as a therapeutic strategy for a primary mitochondrial disease where transient liver-targeted expression is sufficient to correct a systemic metabolic defect. More broadly, our results support the development of mRNA-LNP therapeutics and their subcutaneous delivery as a generalizable platform for treating monogenic diseases, through repeatable, non-viral protein replacement.

pharmacology and toxicology↗

Whole-body Super-resolution Functional and Molecular Imaging with Panoramic Photoacoustic-Ultrasound Tomography

Photoacoustic (PA) and ultrasound (US) imaging provide complementary molecular, functional, and anatomical contrasts. Here, we present a panoramic PA-US imaging platform that integrates multispectral PA computed tomography (PACT) along with reflection-mode and transmission-mode US imaging through a single shared full-ring ultrasound array. We employ an ultrafast planewave transmission scheme in reflection-mode US for power Doppler (PWD) imaging and ultrasound localization microscopy (ULM). Additionally, we use the transmission-mode US to reconstruct a spatially resolved speed of sound (SoS) map that corrects both PA and US reconstruction. Such correction sharpens the resolution of PACT, suppresses the artifacts of PWD, and improves microbubble localization of ULM. Elevational scanning further enables whole-body volumetric imaging with co-registered PA and US contrasts. The integrated system maps photoswitchable DrBphP1-expressing tumors alongside their blood perfusion and oxygenation environment. Applying the platform to monitor unilateral renal ischemia-reperfusion injury, we report that microvascular perfusion and renal oxygenation recover at different rates. Collectively, we demonstrate that the integrated PA-US imaging platform provides a unified framework for multiparametric study of anatomy, perfusion, microvascular flow, oxygenation, and molecular activities.

bioengineering↗

Unmasking Early Renal Fibrosis in Polycystic Kidney Disease Using Noninvasive Precision Molecular MRI of Collagen

Fibrotic remodeling of extracellular matrix is a central driver of autosomal dominant polycystic kidney disease (ADPKD) progression since early stages of the disease. Unfortunately, it cannot be assessed with currently available methodologies before irreversible structural and functional decline, creating a diagnostic blind spot that hinders accurate early risk stratification and management. Here, we report the development of Gd-hProCA32.Collagen, a collagen -targeted protein MRI contrast agent that enables precision molecular MRI (pMRI) of early fibrosis by directly imaging collagen type I deposition in vivo before conventional laboratory and imaging methods detect changes in kidneys and liver of Pkhd1PCK/PCK (PCK) rats and Pkd2 mutant mice. Gd-hProCA32.Collagen, used at 10-fold lower dose, outperformed the widely clinically used agent gadobutrol (Gadovist), detecting approximately 2.8-fold greater total renal cyst volume ([~]8,500 vs [~]3,000 mm3, p<0.0001) and 1.5-fold higher total cyst count ([~]245 vs [~]160, p<0.0001), with superior T1W and T2W kidney AUC (p<0.01 and p<0.001) and preferential sensitivity to small and medium cysts. Signal enhancement in kidneys and liver correlated strongly with histological collagen burden quantified by Sirius red staining, whereas Gadovist showed no meaningful correlation. Gd-hProCA32.Collagen also enabled in vivo visualization of previously undetectable changes resembling radial striations at sites of microcyst cluster-adjacent microfibrosis and sustained delayed MRI enhancement due to specific collagen binding. These results reveal a previously inaccessible subclinical fibrotic phase of cystic kidney and liver disease and establish collagen-targeted pMRI as a strategy for early noninvasive detection and spatial mapping of multi-organ extracellular matrix remodeling when conventional biomarkers remain non-discriminating. One-sentence summaryWe report a first-in-class collagen-targeted MRI contrast agent with Precision molecular MRI that noninvasively reveals a previously inaccessible subclinical fibrotic phase of polycystic kidney disease across kidney and liver, overcoming limitations of current diagnostic methodology.

molecular biology↗

BiomarkerKB: FAIR and Integrated Biomarker Knowledge Connecting Biomolecular and Clinical Data Types

Biomarkers are essential tools for disease detection, risk assessment, therapeutic monitoring, and precision medicine. However, biomarker data are dispersed across heterogeneous resources, inconsistently reported in the literature, and rarely standardized for computational use. This fragmentation limits reproducibility, cross-study integration, and the discovery of novel biomarker and disease relationships. We developed BiomarkerKB, a knowledgebase designed to harmonize and integrate biomarker information under a standardized data model. The model follows the FDA-NIH BEST biomarker definition and captures both core fields (biomarker entity, disease/condition, exposure agent) and contextual metadata (specimen, biomarker role, evidence, provenance). Biomarker data and related annotations were either curated from publications or collected from public resources (e.g., OpenTargets, GWAS Catalog, ClinVar, CIViC, OncoMX) and were also contributed by the Common Fund Data Coordinating Centers and the Early Detection Research Network (EDRN). Standardization was achieved using ontologies and reference resources such as Disease Ontology, UBERON, UniProtKB, and HUGO Gene Nomenclature Committee (HGNC) gene symbols. BiomarkerKB data were ingested into a Neo4j-based knowledge graph and integrated with the Common Fund Data Ecosystem (CFDE) Knowledge Graph. The initial release of BiomarkerKB contains over 200,000 biomarker-disease associations spanning genes, proteins, metabolites, glycans, and chemical elements. The knowledge graph comprises more than 300,000 nodes and 1.2 million edges, enabling structured exploration of biomarker relationships within CFDE data as demonstrated through the knowledge graph query-based use cases presented in this study. A publicly accessible web portal (https://biomarkerkb.org) provides keyword search, filtering, data downloads, and access to graph visualization to support both researchers and computational analyses. BiomarkerKB addresses a critical gap in biomarker informatics by providing an integrated, FAIR (Findable, Accessible, Interoperable, and Reusable), and unified framework for biomarker knowledge exploration and discovery.

bioinformatics↗

The Genomic Architecture of Human DNA Replication Origins

The exact sites of DNA replication origins in human and other metazoans remain elusive. Examining human whole-genome sequencing data of 2,616 specimens, we observed conjoining reads at 2,025,756 non-random genomic positions, likely arising from nascent DNA and thus defining replication origins. These origins exhibited a 16 bp motif and periodic occurrence at the intervals of 10.5 bp and 200 bp. Genome-wide replication activity is related to the expression of DNA replication-related genes. Across the genome, DNA replication initiation is more active in early replicating regions, correlated with transcription activity in cis, enriched for de novo mutations and trait-associated polymorphisms. Our high-resolution mapping of human DNA replication origins points to molecular features that govern where and when replication begins in the genome.

cell biology↗

The Data Distillery: A Graph Framework for Semantic Integration and Querying of Biomedical Data

The Data Distillery Knowledge Graph (DDKG) is a framework for semantic integration and querying of biomedical data across domains. Built for the NIH Common Fund Data Ecosystem, it supports translational research by linking clinical and experimental datasets in a unified graph model. Clinical standards such as ICD-10, SNOMED, and DrugBank are integrated through UMLS, while genomics and basic science data are structured using ontologies and standards such as HPO, GENCODE, Ensembl, STRING, and ClinVar. The DDKG uses a property graph architecture based on the UBKG infrastructure and supports ontology-based ingestion, identifier normalization, and graph-native querying. The system is modular and can be extended with new datasets or schema modules. We demonstrate its utility for informatics queries across eight use cases, including regulatory variant analysis, tissue-specific expression, biomarker discovery, and cross-species variant prioritization. The DDKG is accessible via a public interface, a programmatic API, and downloadable builds for local use.

bioinformatics↗

LCK-targeting molecular glues overcome resistance to inhibitor-based therapy in T-cell acute lymphoblastic leukemia

Drug resistance is a major challenge in cancer therapy, especially in the context of kinase inhibitors. While targeted protein degradation (TPD) was a distinct mode of action compared to inhibition-based therapeutic targeting, the potential value of TPD in drug-resistant cancer remains unclear. Here, we report the discovery of cereblon-recruiting molecular glue degraders (MGDs) targeting LCK, an oncogenic kinase in T-cell acute lymphoblastic leukemia (T-ALL). By high-throughput screening and medicinal chemistry optimization, we developed a series of MGDs that induced CRBN-dependent degradation of LCK as well as potent cytotoxicity in T-ALL in vitro. Structure-activity relationship analysis and ternary complex modeling revealed a non-canonical degron at the LCK-CRBN interface involving the G-loop, whose mutation disrupts this interaction. Unlike inhibitors and inhibitor-based PROTACs, these MGDs engage LCK in regions distal to the ATP binding site and thus their activities in T-ALL are not affected by gate-keeper LCK mutations that drive resistance to inhibitor-based therapeutics. Taken together, our data underscore the potential of LCK-targeting MGDs as a strategy to overcome kinase inhibitor resistance in T-ALL, highlighting a potentially generalizable strategy in cancer therapy.

cancer biology↗

Uridine Metabolism as a Targetable Metabolic Achilles' Heel for chemo-resistant B-ALL

Relapse continues to limit survival for patients with B-cell acute lymphoblastic leukemia (B-ALL). Previous studies have independently implicated activation of B-cell developmental signaling pathways and increased glucose consumption with chemo-resistance and relapse risk. Here, we connect these observations, demonstrating that B-ALL cells with active signaling, defined by high expression of phosphorylated ribosomal protein S6 ("pS6+ cells"), are metabolically unique and glucose dependent. Isotope tracing and metabolic flux analysis confirm that pS6+ cells are highly glycolytic and notably sensitive to glucose deprivation, relying on glucose for de novo nucleotide synthesis. Uridine, but not purine or pyrimidine, rescues pS6+ cells from glucose deprivation, highlighting uridine is essential for their survival. Active signaling in pS6+ cells drives uridine production through activating phosphorylation of carbamoyl phosphate synthetase (CAD), the enzyme catalyzing the initial steps of uridine synthesis. Inhibition of signaling abolishes glucose dependency and CAD phosphorylation in pS6+ cells. Primary pS6+ cells demonstrate high expression of uridine synthesis proteins, including dihydroorotate dehydrogenase (DHODH), the rate-limiting catalyst of de novo uridine synthesis. Gene expression demonstrates that increased expression of DHODH is associated with relapse and inferior event-free survival after chemotherapy. Further, the majority of B-ALL genomic subtypes demonstrate activity of DHODH. Inhibiting DHODH using BAY2402232 effectively kills pS6+ cells in vitro, with its IC50 correlated with the strength of pS6 signaling across 14 B-ALL cell lines and patient-derived xenografts (PDX). In vivo DHODH inhibition prolongs survival and decreases leukemia burden in pS6+ B-ALL cell line and PDX models. These findings link active signaling to uridine dependency in B-ALL cells and an associated risk of relapse. Targeting uridine synthesis through DHODH inhibition offers a promising therapeutic strategy for chemo-resistant B-ALL as a novel therapeutic approach for resistant disease.

cancer biology↗

Molecular and Pathological Characterization of Cervicovaginal Specimens Evince Significant Protection Against HPV Infections, Bacterial Vaginosis, and Epithelial Cell Abnormalities by Lactobacillus species

BackgroundBacterial vaginosis (BV) results in dysbiosis in the vaginal microbiome and facilitates secondary human papilloma virus (HPV) infections, which can cause cervical abnormalities. The effects of Lactobacilli on BV-HPV infections and cervicovaginal pathology were investigated. MethodElectronic molecular and cytology laboratory results, and demographic records of 19,105 females screened for BV, HPV, and cervical cancer between August 2021 and April 2023 were collected. After data cleaning and reorganization, 15, 607 sample results were used. The data was subjected to epidemiological, statistical, and machine learning analyses to identify patterns, correlations, associations, and interactive effects of age, State, Lactobacilli, BV-associated pathogens, high-risk HPV (hrHPV) genotypes, BV, and cervical cytology. ResultsThe final dataset comprised of data from anonymized females (n = 15541, 99.57%), males (n = 13, 0.08%) and unknown gender (n = 53, 0.34%) between 14 and 95 years from 32 States and Washington D.C. Most samples were BV positive (n = 8282, 53.07%) and/or NILM (n = 11749) followed by 14.29% ASCUS (n = 2231), 7.14% LSIL (n = 1115), 1.04% RCC (n = 163), 0.53% HSIL (n = 82), 0.39% ASC-H (n = 61), and 0.16% AGC (n = 25). HPV-positive samples had higher BV pathogens and BV-positive diagnosis (between 51.90% and 68.60%) than BV-negative diagnosis. Lactobacillus gasseri (79.75%), Lactobacillus jensenii (82.68%), Lactobacillus crispatus (90.91%) were mostly found in BV-negative and NILM specimens. BV and ECA outcomes were significantly associated with age and State. Statistical, correlation, and machine learning models predictively confirmed these findings. ConclusionL. crispatus, followed by L. gasseri and L. jensenii, significantly maintains a healthy cervicovaginal microbiome by inhibiting harmful bacterial pathogens and high-risk HPV subtypes; L. iners have an opposing or neutral effect. Lay summary/importance/highlightsBacterial vaginosis (BV) and human papillomavirus (HPV) infections mostly occur in sexually active and reproductive-age women, adversely affecting their quality of life and predisposing them to sequelae of reproductive disorders. In this study, the protective effects of Lactobacilli against BV and HPV infections to maintain a healthy cervicovaginal microbiome were investigated. Lactobacillus crispatus, L. gasseri, and L. jensenii were common in clinical specimens that had no or relatively lower concentrations of hrHPV, BV, and cervico-vaginal cell abnormalities and vice versa. This shows how important these Lactobacilli are in maintaining a healthy cervix and vagina. Age and BV were found to be strongly associated with the incidence of HPV infections and epithelial cell abnormalities (ECAs). Some States had higher prevalence of BV and ECAs than others. Co-infection with multiple hrHPV and/or hrHPV-BV pathogens segued into negative health effects; some interactions were beneficial for the microbiome, albeit those were few. This makes multiple HPV genotype infections dangerous.

pathology↗

Metabolic vulnerabilities in Down syndrome B-cell acute lymphoblastic leukemia can be targeted using Venetoclax

Children with Down syndrome (DS) and B-cell acute lymphoblastic leukemia (B-ALL) are at increased risk for treatment-related mortality and relapse, highlighting the need for new therapies. Leukemia cell lines (CLs) have been fundamental to understanding therapeutic responses to pharmacological agents. We generated three DS B-ALL CLs characterized with diverse genomic alterations, including IGH::CRLF2 rearrangement (BCR::ABL1 like), mutations in FLT3 and TP53, and a novel ERG::CEBPD rearrangement. DS CLs had diminished proliferation, metabolism, and mitochondrial function when compared to non-DS (NDS) CLs and interestingly, these findings were similar to NDS Philadelphia chromosome-like (Ph-like) B-ALL CLs. Based on similar mitochondrial defects and prior preclinical data using Venetoclax for Ph-like B-ALL, we hypothesized that Venetoclax would be effective in DS. Intriguingly, Venetoclax was more effective in DS when compared to both NDS and Ph-like CLs. Efficacy was observed in DS patient derived xenografts (PDXs) and diagnostic/relapsed patient samples treated with Venetoclax, which synergized with Trametinib and Vincristine. Mass spectrometry-based multiomics analyses in DS and NDS B-ALL patient samples revealed an enriched metabolite profile in DS, particularly in the hubs of glucose metabolism and polyunsaturated phosphatidylcholines and phosphatidylinositols. Transcriptome analyses in DS B-ALL patients (n=249) supported enhanced glucose and fatty acid metabolism. Glucose regulated B-ALL viability through de novo serine biosynthesis. Targeting serine synergized with Venetoclax in DS B-ALL CLs. In summary, we have generated novel tools for studying DS B-ALL and identify altered metabolism in DS that responds to Venetoclax.

cancer biology↗

Organellular imaging in vivo reveals a depletion of endoplasmic reticular calcium during post-ictal cortical spreading depolarization

AO_SCPLOWBSTRACTC_SCPLOWDuring cortical spreading depolarization (CSD), neurons exhibit a dramatic increase in cytosolic calcium, which may be integral to CSD-mediated seizure termination. This calcium increase greatly exceeds that during seizures, suggesting the calcium source may not be solely extracellular. Thus, we sought to determine if the endoplasmic reticulum (ER), the largest intracellular calcium store, is involved. We developed a two-photon calcium imaging paradigm to simultaneously record the cytosol and ER during seizures in awake mice. Paired with direct current recording, we reveal that CSD can manifest as a slow post-ictal cytosolic calcium wave with a concomitant depletion of ER calcium that is spatiotemporally consistent with a calcium-induced calcium release. Importantly, we observed both naturally occurring and electrically induced CSD suppressed post-ictal epileptiform activity. Collectively, this work links ER dynamics to CSD, which serves as an innate process for seizure suppression and a potential mechanism underlying therapeutic electrical stimulation for epilepsy.

neuroscience↗

Bootstrap Evaluation of Association Matrices (BEAM) for Integrating Multiple Omics Profiles with Multiple Outcomes

MotivationLarge datasets containing multiple clinical and omics measurements for each subject motivate the development of new statistical methods to integrate these data to advance scientific discovery. ModelWe propose bootstrap evaluation of association matrices (BEAM), which integrates multiple omics profiles with multiple clinical endpoints. BEAM associates a set omic features with clinical endpoints via regression models and then uses bootstrap resampling to determine statistical significance of the set. Unlike existing methods, BEAM uniquely accommodates an arbitrary number of omic profiles and endpoints. ResultsIn simulations, BEAM performed similarly to the theoretically best simple test and outperformed other integrated analysis methods. In an example pediatric leukemia application, BEAM identified several genes with biological relevance established by a CRISPR assay that had been missed by univariate screens and other integrated analysis methods. Thus, BEAM is a powerful, flexible, and robust tool to identify genes for further laboratory and/or clinical research evaluation. AvailabilitySource code, documentation, and a vignette for BEAM are available on GitHub at: https://github.com/annaSeffernick/BEAMR. The R package is available from CRAN at: https://cran.r-project.org/package=BEAMR. ContactStanley.Pounds@stjude.org Supplementary InformationSupplementary data are available at the journals website.

bioinformatics↗

Epigenomic mapping in B-cell acute lymphoblastic leukemia identifies transcriptional regulators and noncoding variants promoting distinct chromatin architectures

B-cell lineage acute lymphoblastic leukemia (B-ALL) is comprised of diverse molecular subtypes and while transcriptional and DNA methylation profiling of B-ALL subtypes has been extensively examined, the accompanying chromatin landscape is not well characterized for many subtypes. We therefore mapped chromatin accessibility using ATAC-seq for 10 B-ALL molecular subtypes in primary ALL cells from 154 patients. Comparisons with B-cell progenitors identified candidate B-ALL cell-of-origin and AP-1-associated cis-regulatory rewiring in B-ALL. Cis-regulatory rewiring promoted B-ALL-specific gene regulatory networks impacting oncogenic signaling pathways that perturb normal B-cell development. We also identified that over 20% of B-ALL accessible chromatin sites exhibit strong subtype enrichment, with transcription factor (TF) footprint profiling identifying candidate TFs that maintain subtype-specific chromatin architectures. Over 9000 inherited genetic variants were further uncovered that contribute to variability in chromatin accessibility among individual patient samples. Overall, our data suggest that distinct chromatin architectures are driven by diverse TFs and inherited genetic variants which promote unique gene regulatory networks that contribute to transcriptional differences among B-ALL subtypes. HIGHLIGHTSO_LIPro-B progenitor cells as the most common cell-of-origin for B-ALL C_LIO_LIAP-1 TF-associated cis-regulatory rewiring in B-ALL C_LIO_LISubtype-specific accessible chromatin signatures representing 20% of all B-ALL sites C_LIO_LIRole for distinct TFs in promoting subtype-specific chromatin architectures C_LIO_LIThousands of inherited genetic variants identified impacting chromatin state C_LI

cancer biology↗

Spatiotemporal Dynamics of Vcam1 Regulates Cholangiocarcinoma Mass Expansion and Tumor Dissemination under Growth-suppressive Peritumoral Myofibroblasts

Intrahepatic cholangiocarcinoma (iCCA) is characterized by its highly desmoplastic stroma. Myofibroblasts (MFs) are present both within the tumor mass (intratumoral MFs, iMFs) and at the tumor border (peritumoral MFs, pMFs). Using a spheroid-based coculture system, we show that the initial iCCA-pMF contact is growth suppressive to the tumor cells. However, prolonged iCCA-pMF interaction elicits significant tumor cell invasion and dissemination. We find that vascular cell adhesion molecule-1 (Vcam1) level is elevated in tumor cells in contact with pMFs but low in disseminated tumor cells both in vitro and in vivo. A gene regulatory network analysis of mouse and patient iCCA tumors and Vcam1 knockout (Vcam1KO) demonstrate a heavy involvement of Vcam1 in epithelial-to-mesenchymal transition. While Vcam1KO has only a limited impact on tumor cell growth in their monoculture, Vcam1KO spheroids exhibit instant dissemination and a severe growth defect when cocultured with pMFs. When transplanted into the liver, Vcam1KO iCCA cells show a similar increase in dissemination but a significant defect in establishing primary and metastatic tumors. Incomplete blocking of Vcam1 in vivo reduces the size but increase the number of metastatic lesions. Overall, our study shows a spatiotemporal regulation of iCCA growth and dissemination by pMFs in a Vcam1-dependent manner.

cancer biology↗

ReproTox-KG: Toxicology Knowledge Graph for Structural Birth Defects

Birth defects are functional and structural abnormalities that impact 1 in 33 births in the United States. Birth defects have been attributed to genetic as well as other factors, but for most birth defects there are no known causes. Small molecule drugs, cosmetics, foods, and environmental pollutants may cause birth defects when the mother is exposed to them during pregnancy. These molecules may interfere with the process of normal fetal development. To characterize associations between small molecule compounds and their potential to induce specific birth abnormalities, we gathered knowledge from multiple sources to construct a reproductive toxicity Knowledge Graph (ReproTox-KG) with an initial focus on associations between birth defects, drugs, and genes. Specifically, to construct ReproTox-KG we gathered data from drug/birth-defect associations from co-mentions in published abstracts, gene/birth-defect associations from genetic studies, drug- and preclinical-compound-induced gene expression data, known drug targets, genetic burden scores for all human genes, and placental crossing scores for all small molecules in ReproTox-KG. Using the data stored within ReproTox-KG, we scored 30,000 preclinical small molecules for their potential to induce birth defects. Querying the ReproTox-KG, we identified over 500 birth-defect/gene/drug cliques that can be used to explain molecular mechanisms for drug-induced birth defects. The ReproTox-KG is provided as curated tables and via a web-based user interface that can enable users to explore the associations between birth defects, approved and preclinical drugs, and human genes.

bioinformatics↗

Arc ubiquitination regulates endoplasmic reticulum-mediated Ca2+ release and CaMKII signaling

Synaptic plasticity relies on rapid, yet spatially precise signaling to alter synaptic strength. Arc is a brain enriched protein that is rapidly expressed during learning-related behaviors and is essential for regulating metabotropic glutamate receptor-mediated long-term depression (mGluR-LTD). We previously showed that disrupting the ubiquitination capacity of Arc enhances mGluR-LTD; however, the mechanism by which this occurs and its consequences on other mGluR-mediated signaling events is unknown. Here we show that disrupting Arc ubiquitination on key amino acid residues leads to derangements in Ca2+ release from the endoplasmic reticulum (ER) during pharmacological activation of Group I mGluRs. These alterations were observed in all neuronal subregions except secondary branchpoints. Deficits in Arc ubiquitination increased Arc self-association and enhanced its interaction with calcium/calmodulin-dependent protein kinase IIb (CaMKIIb) and constitutively active forms of CaMKII. Notably, these interactions were also excluded at secondary branchpoints. Finally, disruptions in Arc ubiquitination were found to increase Arc interaction with the integral ER protein Calnexin. These results suggest a previously unknown role for Arc ubiquitination in the fine tuning of ER-mediated Ca2+ signaling that is needed for mGluR-LTD, which in turn, may regulate CaMKII and its interactions with Arc.

neuroscience↗

Exercise Training Remodels Adipocyte-Specific Extracellular Matrix Proteins and Alters Innervation and Vascularization in Inguinal White Adipose Tissue (iWAT)

Inguinal white adipose tissue (iWAT) is essential for the beneficial effects of exercise training on metabolic health. Extracellular matrix (ECM) composition, innervation, and vascularization are all important regulators of iWAT function, yet whether exercise training improves these structural components of iWAT is unknown. Using biochemical, imaging, and multi-omics analyses we find that 11-days of wheel running in male mice causes profound iWAT remodeling including decreased ECM deposition and increased vascularization and innervation. We identify adipose stem cells as the main contributors to training-induced ECM remodeling, determine that training causes a shift from hypertrophic to insulin-sensitive adipocyte subpopulations, show that the PRDM16 transcriptional complex is necessary for iWAT remodeling and beiging, and discover neuronal growth regulator 1 (NEGR1) as a link between PRDM16 and neuritogenesis. Exercise training leads to remarkable adaptations to iWAT structure and cell-type composition that can confer beneficial changes in tissue metabolism. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=139 SRC="FIGDIR/small/503375v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@fd590eorg.highwire.dtl.DTLVardef@e1dd02org.highwire.dtl.DTLVardef@74be24org.highwire.dtl.DTLVardef@6f6e58_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗