Digital Commons Network^™

Trex2 Deficiency Suppresses Spontaneous And Genotoxin-Associated Mutagenesis, Teresa Marple, Mi Young Son, Xiaodong Cheng, Jun Ho Ko, Patrick Sung, Paul Hasty

Faculty, Staff and Student Publications

TREX2, a 3'-5' exonuclease, is a part of the DNA damage tolerance (DDT) pathway that stabilizes replication forks (RFs) by ubiquitinating PCNA along with the ubiquitin E3 ligase RAD18 and other DDT factors. Mismatch repair (MMR) corrects DNA polymerase errors, including base mismatches and slippage. Here we demonstrate that TREX2 deletion reduces mutations in cells upon exposure to genotoxins, including those that cause base lesions and DNA polymerase slippage. Importantly, we show that TREX2 generates most of the spontaneous mutations in MMR-mutant cells derived from mice and people. TREX2-induced mutagenesis is dependent on the nuclease and DNA-binding attributes of TREX2. …

Non-Canonical Hedgehog Signaling Mediates Profibrotic Hematopoiesis-Stroma Crosstalk In Myeloproliferative Neoplasms, Jessica E Pritchard, Juliette E Pearce, Inge A M Snoeren, Stijn N R Fuchs, Katrin Götz, Fabian Peisker, Silke Wagner, Adam Benabid, Niklas Lutterbach, Vanessa Klöker, James S Nagai, Monica T Hannani, Anna K Galyga, Ellen Sistemich, Bella Banjanin, Niclas Flosdorf, Eric Bindels, Kathrin Olschok, Katharina Biaesch, Nicolas Chatain, Neha Bhagwat, Andrew Dunbar, Rita Sarkis, Olaia Naveiras, Marie-Luise Berres, Steffen Koschmieder, Ross L Levine, Ivan G Costa, Hélène F E Gleitz, Rafael Kramann, Rebekka K Schneider

Faculty, Staff and Student Publications

The role of hematopoietic Hedgehog signaling in myeloproliferative neoplasms (MPNs) remains incompletely understood despite data suggesting that Hedgehog (Hh) pathway inhibitors have therapeutic activity in patients. We aim to systematically interrogate the role of canonical vs. non-canonical Hh signaling in MPNs. We show that Gli1 protein levels in patient peripheral blood mononuclear cells (PBMCs) mark fibrotic progression and that, in murine MPN models, absence of hematopoietic Gli1, but not Gli2 or Smo, significantly reduces MPN phenotype and fibrosis, indicating that GLI1 in the MPN clone can be activated in a non-canonical fashion. Additionally, we establish that hematopoietic Gli1 has a …

Integrative Genomic Analyses Reveal Putative Cell Type-Specific Targets Of The Drosophila Ets Transcription Factor Pointed, Komal Kumar Bollepogu Raja, Kelvin Yeung, Yoon-Kyung Shim, Graeme Mardon

Faculty, Staff and Students Publications

The Ets domain transcription factors direct diverse biological processes throughout all metazoans and are implicated in development as well as in tumor initiation, progression and metastasis. The Drosophila Ets transcription factor Pointed (Pnt) is the downstream effector of the Epidermal growth factor receptor (Egfr) pathway and is required for cell cycle progression, specification, and differentiation of most cell types in the larval eye disc. Despite its critical role in development, very few targets of Pnt have been reported previously. Here, we employed an integrated approach by combining genome-wide single cell and bulk data to identify putative cell type-specific Pnt targets. …

Cpsa Mediates Infection Of Recruited Lung Myeloid Cells By Mycobacterium Tuberculosis, Steven J Grigsby, G V R Krishna Prasad, Joshua B Wallach, Ekansh Mittal, Fong-Fu Hsu, Dirk Schnappinger, Jennifer A Philips

2020-Current year OA Pubs

Mycobacterium tuberculosis (Mtb) possesses an arsenal of virulence factors to evade host immunity. Previously, we showed that the Mtb protein CpsA, which protects Mtb against the host NADPH oxidase, is required in mice during the first 3 weeks of infection but is thereafter dispensable for full virulence. Using flow cytometry, we find that ΔcpsA Mtb is retained in alveolar macrophages, impaired in recruiting and disseminating into monocyte-derived cells, and more likely to be localized in airway cells than wild-type Mtb. The lungs of ΔcpsA-infected mice also have markedly fewer antigen-specific T cells, indicating a delay in adaptive immunity. Thus, we …

Neuronal Deletion Of The Circadian Clock Gene Bmal1 Induces Cell-Autonomous Dopaminergic Neurodegeneration, Michael K. Kanan, Patrick W. Sheehan, Jessica N. Haines, Pedro G. Gomez, Adya Dhuler, Collin J. Nadarajah, Zachary M. Wargel, Brittany M. Freeberg, Hemanth R. Nelvagal, Mariko Izumo, Joseph S. Takahashi, Jonathan D. Cooper, Albert A. Davis, Erik S. Musiek

2020-Current year OA Pubs

Circadian rhythm dysfunction is a hallmark of Parkinson disease (PD), and diminished expression of the core clock gene Bmal1 has been described in patients with PD. BMAL1 is required for core circadian clock function but also serves nonrhythmic functions. Germline Bmal1 deletion can cause brain oxidative stress and synapse loss in mice, and it can exacerbate dopaminergic neurodegeneration in response to the toxin MPTP. Here we examined the effect of cell type-specific Bmal1 deletion on dopaminergic neuron viability in vivo. We observed that global, postnatal deletion of Bmal1 caused spontaneous loss of tyrosine hydroxylase+ (TH+) dopaminergic neurons in the substantia …

Acetylcholine Receptor Based Chemogenetics Engineered For Neuronal Inhibition And Seizure Control Assessed In Mice, Quynh-Anh Nguyen, Peter M Klein, Cheng Xie, Katelyn N Benthall, Jillian Iafrati, Jesslyn Homidan, Jacob T Bendor, Barna Dudok, Jordan S Farrell, Tilo Gschwind, Charlotte L Porter, Annahita Keravala, G Steven Dodson, Ivan Soltesz

Faculty, Staff and Students Publications

Epilepsy is a prevalent disorder involving neuronal network hyperexcitability, yet existing therapeutic strategies often fail to provide optimal patient outcomes. Chemogenetic approaches, where exogenous receptors are expressed in defined brain areas and specifically activated by selective agonists, are appealing methods to constrain overactive neuronal activity. We developed BARNI (Bradanicline- and Acetylcholine-activated Receptor for Neuronal Inhibition), an engineered channel comprised of the α7 nicotinic acetylcholine receptor ligand-binding domain coupled to an α1 glycine receptor anion pore domain. Here we demonstrate that BARNI activation by the clinical stage α7 nicotinic acetylcholine receptor-selective agonist bradanicline effectively suppressed targeted neuronal activity, and controlled both …

In-Patient Evolution Of A High-Persister Escherichia Coli Strain With Reduced In Vivo Antibiotic Susceptibility, Joshua B Parsons, Ashelyn E Sidders, Amanda Z Velez, Blake M Hanson, Michelle Angeles-Solano, Felicia Ruffin, Sarah E Rowe, Cesar A Arias, Vance G Fowler, Joshua T Thaden, Brian P Conlon

Faculty, Staff and Student Publications

Gram-negative bacterial bloodstream infections (GNB-BSI) are common and frequently lethal. Despite appropriate antibiotic treatment, relapse of GNB-BSI with the same bacterial strain is common and associated with poor clinical outcomes and high healthcare costs. The role of persister cells, which are sub-populations of bacteria that survive for prolonged periods in the presence of bactericidal antibiotics, in relapse of GNB-BSI is unclear. Using a cohort of patients with relapsed GNB-BSI, we aimed to determine how the pathogen evolves within the patient between the initial and subsequent episodes of GNB-BSI and how these changes impact persistence. Using

Novel Pan-Err Agonists Ameliorate Heart Failure Through Enhancing Cardiac Fatty Acid Metabolism And Mitochondrial Function, Weiyi Xu, Cyrielle Billon, Hui Li, Andrea Wilderman, Lei Qi, Andrea Graves, Jernie Rae Dela Cruz Rideb, Yuanbiao Zhao, Matthew Hayes, Keyang Yu, Mckenna Losby, Carissa S Hampton, Christiana M Adeyemi, Seok Jae Hong, Eleni Nasiotis, Chen Fu, Tae Gyu Oh, Weiwei Fan, Michael Downes, Ryan D Welch, Ronald M Evans, Aleksandar Milosavljevic, John K Walker, Brian C Jensen, Liming Pei, Thomas Burris, Lilei Zhang

Faculty, Staff and Students Publications

BACKGROUND: Cardiac metabolic dysfunction is a hallmark of heart failure (HF). Estrogen-related receptors ERRα and ERRγ are essential regulators of cardiac metabolism. Therefore, activation of ERR could be a potential therapeutic intervention for HF. However, in vivo studies demonstrating the potential usefulness of ERR agonist for HF treatment are lacking, because compounds with pharmacokinetics appropriate for in vivo use have not been available.

METHODS: Using a structure-based design approach, we designed and synthesized 2 structurally distinct pan-ERR agonists, SLU-PP-332 and SLU-PP-915. We investigated the effect of ERR agonist on cardiac function in a pressure overload-induced HF model in vivo. We …

Hormonal Basis Of Sex Differences In Anesthetic Sensitivity, Andrzej Z Wasilczuk, Cole Rinehart, Adeeti Aggarwal, Martha E Stone, George A Mashour, Michael S Avidan, Max B Kelz, Alex Proekt, Reccognition Study Group

2020-Current year OA Pubs

General anesthesia-a pharmacologically induced reversible state of unconsciousness-enables millions of life-saving procedures. Anesthetics induce unconsciousness in part by impinging upon sexually dimorphic and hormonally sensitive hypothalamic circuits regulating sleep and wakefulness. Thus, we hypothesized that anesthetic sensitivity should be sex-dependent and modulated by sex hormones. Using distinct behavioral measures, we show that at identical brain anesthetic concentrations, female mice are more resistant to volatile anesthetics than males. Anesthetic sensitivity is bidirectionally modulated by testosterone. Castration increases anesthetic resistance. Conversely, testosterone administration acutely increases anesthetic sensitivity. Conversion of testosterone to estradiol by aromatase is partially responsible for this effect. In contrast, …

Ephrinb2 Knockdown In Cervical Spinal Cord Preserves Diaphragm Innervation In A Mutant Sod1 Mouse Model Of Als, Mark W. Urban, Brittany A. Charsar, Nicolette M. Heinsinger, Shashirekha S. Markandaiah, Lindsay Sprimont, Wei Zhou, Eric V. Brown, Nathan T. Henderson, Samantha J. Thomas, Biswarup Ghosh, Rachel E. Cain, Davide Trotti, Piera Pasinelli, Megan C. Wright, Matthew B. Dalva, Angelo C. Lepore

Farber Institute for Neuroscience Staff Papers and Presentations

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron loss. Importantly, non-neuronal cell types such as astrocytes also play significant roles in disease pathogenesis. However, mechanisms of astrocyte contribution to ALS remain incompletely understood. Astrocyte involvement suggests that transcellular signaling may play a role in disease. We examined contribution of transmembrane signaling molecule ephrinB2 to ALS pathogenesis, in particular its role in driving motor neuron damage by spinal cord astrocytes. In symptomatic SOD1G93A mice (a well-established ALS model), ephrinB2 expression was dramatically increased in ventral horn astrocytes. Reducing ephrinB2 in the cervical spinal cord ventral horn via …

Rreb1 Regulates Neuronal Proteostasis And The Microtubule Network., Emily N Griffin, Thomas Jucius, Su-Eon Sim, Belinda S. Harris, Sven Heinz, Susan L Ackerman

Faculty Research 2024

Transcription factors play vital roles in neuron development; however, little is known about the role of these proteins in maintaining neuronal homeostasis. Here, we show that the transcription factor RREB1 (Ras-responsive element-binding protein 1) is essential for neuron survival in the mammalian brain. A spontaneous mouse mutation causing loss of a nervous system–enriched Rreb1 transcript is associated with progressive loss of cerebellar Purkinje cells and ataxia. Analysis of chromatin immunoprecipitation and sequencing, along with RNA sequencing data revealed dysregulation of RREB1 targets associated with the microtubule cytoskeleton. In agreement with the known role of microtubules in dendritic development, dendritic complexity …

A Flexible, Quantitative Plasmonic-Fluor Lateral Flow Assay For The Rapid Detection Of Orthoebolavirus Zairense And Orthoebolavirus Sudanense, Abraham J Qavi, Qisheng Jiang, M Javad Aman, Hong Vu, Larry Zetlin, John M Dye, Jeffrey W Froude, Daisy W Leung, Frederick Holtsberg, Scott L Crick, Gaya K Amarasinghe

2020-Current year OA Pubs

Filoviruses comprise a family of single-stranded, negative-sense RNA viruses with a significant impact on human health. Given the risk for disease outbreaks, as highlighted by the recent outbreaks across Africa, there is an unmet need for flexible diagnostic technologies that can be deployed in resource-limited settings. Herein, we highlight the use of plasmonic-fluor lateral flow assays (PF-LFA) for the rapid, quantitative detection of an Ebolavirus-secreted glycoprotein, a marker for infection. Plasmonic fluors are a class of ultrabright reporter molecules that combine engineered nanorods with conventional fluorophores, resulting in improved analytical sensitivity. We have developed a PF-LFA for

Tfeb Drives Mtorc1 Hyperactivation And Kidney Disease In Tuberous Sclerosis Complex, Nicola Alesi, Damir Khabibullin, Dean M Rosenthal, Elie W Akl, Pieter M Cory, Michel Alchoueiry, Samer Salem, Melissa Daou, William F Gibbons, Jennifer A Chen, Long Zhang, Harilaos Filippakis, Laura Graciotti, Caterina Miceli, Jlenia Monfregola, Claudia Vilardo, Manrico Morroni, Chiara Di Malta, Gennaro Napolitano, Andrea Ballabio, Elizabeth P Henske

Duncan NRI Faculty and Staff Publications

Tuberous Sclerosis Complex (TSC) is caused by TSC1 or TSC2 mutations, leading to hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) and lesions in multiple organs including lung (lymphangioleiomyomatosis) and kidney (angiomyolipoma and renal cell carcinoma). Previously, we found that TFEB is constitutively active in TSC. Here, we generated two mouse models of TSC in which kidney pathology is the primary phenotype. Knockout of TFEB rescues kidney pathology and overall survival, indicating that TFEB is the primary driver of renal disease in TSC. Importantly, increased mTORC1 activity in the TSC2 knockout kidneys is normalized by TFEB knockout. In TSC2-deficient …

Effects Of Kras Genetic Interactions On Outcomes In Cancers Of The Lung, Pancreas, And Colorectum, Isabella N Grabski, John V Heymach, Kenneth L Kehl, Scott Kopetz, Ken S Lau, Gregory J Riely, Deborah Schrag, Rona Yaeger, Rafael A Irizarry, Kevin M Haigis

Faculty, Staff and Student Publications

Background: KRAS is among the most commonly mutated oncogenes in cancer, and previous studies have shown associations with survival in many cancer contexts. Evidence from both clinical observations and mouse experiments further suggests that these associations are allele- and tissue-specific. These findings motivate using clinical data to understand gene interactions and clinical covariates within different alleles and tissues.

Methods: We analyze genomic and clinical data from the AACR Project GENIE Biopharma Collaborative for samples from lung, colorectal, and pancreatic cancers. For each of these cancer types, we report epidemiological associations for different KRAS alleles, apply principal component analysis (PCA) to …

Investigating Clot-Flow Interactions By Integrating Intravital Imaging With In Silico Modeling For Analysis Of Flow, Transport, And Hemodynamic Forces, Chayut Teeraratkul, Maurizio Tomaiuolo, Timothy Stalker, Debanjan Mukherjee

Cardeza Foundation for Hematologic Research

As a blood clot forms, grows, deforms, and embolizes following a vascular injury, local clot-flow interactions lead to a highly dynamic flow environment. The local flow influences transport of biochemical species relevant for clotting, and determines the forces on the clot that in turn lead to clot deformation and embolization. Despite this central role, quantitative characterization of this dynamic clot-flow interaction and flow environment in the clot neighborhood remains a major challenge. Here, we propose an approach that integrates dynamic intravital imaging with computer geometric modeling and computational flow and transport modeling to develop a unified in silico framework to …

Mechanism Of Anion Exchange And Small-Molecule Inhibition Of Pendrin, Lie Wang, Anthony Hoang, Eva Gil-Iturbe, Arthur Laganowsky, Matthias Quick, Ming Zhou

Faculty, Staff and Students Publications

Pendrin (SLC26A4) is an anion exchanger that mediates bicarbonate (HCO3−) exchange for chloride (Cl−) and is crucial for maintaining pH and salt homeostasis in the kidney, lung, and cochlea. Pendrin also exports iodide (I−) in the thyroid gland. Pendrin mutations in humans lead to Pendred syndrome, causing hearing loss and goiter. Inhibition of pendrin is a validated approach for attenuating airway hyperresponsiveness in asthma and for treating hypertension. However, the mechanism of anion exchange and its inhibition by drugs remains poorly understood. We applied cryo-electron microscopy to determine structures of pendrin from Sus scrofa in the presence of either Cl−, …

Secreted Igm Modulates Il-10 Expression In B Cells, Shannon Mcgettigan, Lazaro Aira, Gaurav Kumar, Romain Ballet, Eugene Butcher, Nicole Baumgarth, Gudrun Debes

Department of Microbiology and Immunology Faculty Papers

IL-10⁺ B cells are critical for immune homeostasis and restraining immune responses in infection, cancer, and inflammation; however, the signals that govern IL-10⁺ B cell differentiation are ill-defined. Here we find that IL-10⁺ B cells expand in mice lacking secreted IgM ((s)IgM^–/–) up to 10-fold relative to wildtype (WT) among all major B cell and regulatory B cell subsets. The IL-10⁺ B cell increase is polyclonal and presents within 24 hours of birth. In WT mice, sIgM is produced prenatally and limits the expansion of IL-10⁺ B cells. Lack of the high affinity …

Inhibiting Metabotropic Glutamate Receptor 5 After Stroke Restores Brain Function And Connectivity, Jakob Hakon, Miriana J Quattromani, Carin Sjölund, Daniela Talhada, Byungchan Kim, Slavianka Moyanova, Federica Mastroiacovo, Luisa Di Menna, Roger Olsson, Elisabet Englund, Ferdinando Nicoletti, Karsten Ruscher, Adam Q Bauer, Tadeusz Wieloch

2020-Current year OA Pubs

Stroke results in local neural disconnection and brain-wide neuronal network dysfunction leading to neurological deficits. Beyond the hyper-acute phase of ischaemic stroke, there is no clinically-approved pharmacological treatment that alleviates sensorimotor impairments. Functional recovery after stroke involves the formation of new or alternative neuronal circuits including existing neural connections. The type-5 metabotropic glutamate receptor (mGluR5) has been shown to modulate brain plasticity and function and is a therapeutic target in neurological diseases outside of stroke. We investigated whether mGluR5 influences functional recovery and network reorganization rodent models of focal ischaemia. Using multiple behavioural tests, we observed that treatment with negative …

Targeting Dna Repair And Survival Signaling In Diffuse Intrinsic Pontine Gliomas To Prevent Tumor Recurrence, Monika Sharma, Ivana Barravecchia, Robert Teis, Jeanette Cruz, Rachel Mumby, Elizabeth K Ziemke, Carlos E Espinoza, Varunkumar Krishnamoorthy, Brian Magnuson, Mats Ljungman, Carl Koschmann, Joya Chandra, Christopher E Whitehead, Judith S Sebolt-Leopold, Stefanie Galban

Faculty, Staff and Student Publications

Therapeutic resistance remains a major obstacle to successful clinical management of diffuse intrinsic pontine glioma (DIPG), a high-grade pediatric tumor of the brain stem. In nearly all patients, available therapies fail to prevent progression. Innovative combinatorial therapies that penetrate the blood-brain barrier and lead to long-term control of tumor growth are desperately needed. We identified mechanisms of resistance to radiotherapy, the standard of care for DIPG. On the basis of these findings, we rationally designed a brain-penetrant small molecule, MTX-241F, that is a highly selective inhibitor of EGFR and PI3 kinase family members, including the DNA repair protein DNA-PK. Preliminary …

Biallelic Variants In Rbm42 Cause A Multisystem Disorder With Neurological, Facial, Cardiac, And Musculoskeletal Involvement, Yiyao Chen, Bingxin Yang, Xiaoyu Merlin Zhang, Songchang Chen, Minhui Wang, Liya Hu, Nina Pan, Shuyuan Li, Weihui Shi, Zhenhua Yang, Li Wang, Yajing Tan, Jian Wang, Yanlin Wang, Qinghe Xing, Zhonghua Ma, Jinsong Li, He-Feng Huang, Jinglan Zhang, Chenming Xu

Faculty, Staff and Students Publications

Here, we report a previously unrecognized syndromic neurodevelopmental disorder associated with biallelic loss-of-function variants in the RBM42 gene. The patient is a 2-year-old female with severe central nervous system (CNS) abnormalities, hypotonia, hearing loss, congenital heart defects, and dysmorphic facial features. Familial whole-exome sequencing (WES) reveals that the patient has two compound heterozygous variants, c.304C>T (p.R102*) and c.1312G>A (p.A438T), in the RBM42 gene which encodes an integral component of splicing complex in the RNA-binding motif protein family. The p.A438T variant is in the RRM domain which impairs RBM42 protein stability in vivo. Additionally, p.A438T disrupts the interaction of …

Heat Shock Factor 1 Directly Regulates Transsulfuration Pathway To Promote Prostate Cancer Proliferation And Survival, J Spencer Hauck, David Moon, Xue Jiang, Mu-En Wang, Yue Zhao, Lingfan Xu, Holly Quang, William Butler, Ming Chen, Everardo Macias, Xia Gao, Yiping He, Jiaoti Huang

Faculty, Staff and Students Publications

There are limited therapeutic options for patients with advanced prostate cancer (PCa). We previously found that heat shock factor 1 (HSF1) expression is increased in PCa and is an actionable target. In this manuscript, we identify that HSF1 regulates the conversion of homocysteine to cystathionine in the transsulfuration pathway by altering levels of cystathionine-β-synthase (CBS). We find that HSF1 directly binds the CBS gene and upregulates CBS mRNA levels. Targeting CBS decreases PCa growth and induces tumor cell death while benign prostate cells are largely unaffected. Combined inhibition of HSF1 and CBS results in more pronounced inhibition of PCa cell …

Crispr-Cas9 Base Editing Of Pathogenic Camkiiδ Improves Cardiac Function In A Humanized Mouse Model, Simon Lebek, Xurde M Caravia, Leon G Straub, Damir Alzhanov, Wei Tan, Hui Li, John R Mcanally, Kenian Chen, Lin Xu, Philipp E Scherer, Ning Liu, Rhonda Bassel-Duby, Eric N Olson

Faculty, Staff and Student Publications

Cardiovascular diseases are the most common cause of worldwide morbidity and mortality, highlighting the necessity for advanced therapeutic strategies. Ca2+/calmodulin-dependent protein kinase IIδ (CaMKIIδ) is a prominent inducer of various cardiac disorders, which is mediated by 2 oxidation-sensitive methionine residues within the regulatory domain. We have previously shown that ablation of CaMKIIδ oxidation by CRISPR-Cas9 base editing enables the heart to recover function from otherwise severe damage following ischemia/reperfusion (IR) injury. Here, we extended this therapeutic concept toward potential clinical translation. We generated a humanized CAMK2D knockin mouse model in which the genomic sequence encoding the entire regulatory domain was …

Serine Synthesis Via Reversed Shmt2 Activity Drives Glycine Depletion And Acetaminophen Hepatotoxicity In Masld, Alia Ghrayeb, Alexandra C Finney, Bella Agranovich, Daniel Peled, Sumit Kumar Anand, M Peyton Mckinney, Mahasen Sarji, Dongshan Yang, Natan Weissman, Shani Drucker, Sara Isabel Fernandes, Jonatan Fernández-García, Kyle Mahan, Zaid Abassi, Lin Tan, Philip L Lorenzi, James Traylor, Jifeng Zhang, Ifat Abramovich, Y Eugene Chen, Oren Rom, Inbal Mor, Eyal Gottlieb

Faculty, Staff and Student Publications

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects one-third of the global population. Understanding the metabolic pathways involved can provide insights into disease progression and treatment. Untargeted metabolomics of livers from mice with early-stage steatosis uncovered decreased methylated metabolites, suggesting altered one-carbon metabolism. The levels of glycine, a central component of one-carbon metabolism, were lower in mice with hepatic steatosis, consistent with clinical evidence. Stable-isotope tracing demonstrated that increased serine synthesis from glycine via reverse serine hydroxymethyltransferase (SHMT) is the underlying cause for decreased glycine in steatotic livers. Consequently, limited glycine availability in steatotic livers impaired glutathione synthesis under acetaminophen-induced oxidative …

Gene Regulation And Speciation In A Migratory Divide Between Songbirds, Matthew I M Louder, Hannah Justen, Abigail A Kimmitt, Koedi S Lawley, Leslie M Turner, J David Dickman, Kira E Delmore

Faculty, Staff and Students Publications

Behavioral variation abounds in nature. This variation is important for adaptation and speciation, but its molecular basis remains elusive. Here, we use a hybrid zone between two subspecies of songbirds that differ in migration - an ecologically important and taxonomically widespread behavior---to gain insight into this topic. We measure gene expression in five brain regions. Differential expression between migratory states was dominated by circadian genes in all brain regions. The remaining patterns were largely brain-region specific. For example, expression differences between the subspecies that interact with migratory state likely help maintain reproductive isolation in this system and were documented in …

Injectable Hydrogel Electrodes As Conduction Highways To Restore Native Pacing, Gabriel J Rodriguez-Rivera, Allison Post, Mathews John, Skylar Buchan, Drew Bernard, Mehdi Razavi, Elizabeth Cosgriff-Hernandez

Faculty, Staff and Students Publications

There is an urgent clinical need for a treatment regimen that addresses the underlying pathophysiology of ventricular arrhythmias, the leading cause of sudden cardiac death. The current report describes the design of an injectable hydrogel electrode and successful deployment in a pig model with access far more refined than any current pacing modalities allow. In addition to successful cardiac capture and pacing, analysis of surface ECG tracings and three-dimensional electroanatomic mapping revealed a QRS morphology comparable to native sinus rhythm, strongly suggesting the hydrogel electrode captures the deep septal bundle branches and Purkinje fibers. In an ablation model, electroanatomic mapping …

C1q Is Elevated During Chronic Staphylococcus Epidermidis Central Nervous System Catheter Infection, Matthew K. Beaver, Lara Bergdolt, Anna Dunaevsky, Tammy Kielian, Gwenn Skar

Journal Articles: Pathology and Microbiology

INTRODUCTION: Significant neurologic morbidity is caused by pediatric cerebrospinal fluid (CSF) shunt infections. The underlying mechanisms leading to impaired school performance and increased risk of seizures are unknown, however, a better understanding of these mechanisms may allow us to temper their consequences. Recent evidence has demonstrated important roles for complement proteins in neurodevelopment and neuroinflammation.

METHODS: We examined complement activation throughout

RESULTS: We found that MASP2 predominated early in catheter infection, but that Factor B was elevated at intermediate time points. Unexpectedly C1q was elevated at late timepoints when bacterial burdens were low or undetectable. Based on these findings and …

Bacterial Single-Cell Rna Sequencing Captures Biofilm Transcriptional Heterogeneity And Differential Responses To Immune Pressure, Lee E. Korshoj, Tammy Kielian

Journal Articles: Pathology and Microbiology

Biofilm formation is an important mechanism of survival and persistence for many bacterial pathogens. These multicellular communities contain subpopulations of cells that display metabolic and transcriptional diversity along with recalcitrance to antibiotics and host immune defenses. Here, we present an optimized bacterial single-cell RNA sequencing method, BaSSSh-seq, to study Staphylococcus aureus diversity during biofilm growth and transcriptional adaptations following immune cell exposure. BaSSSh-seq captures extensive transcriptional heterogeneity during biofilm compared to planktonic growth. We quantify and visualize transcriptional regulatory networks across heterogeneous biofilm subpopulations and identify gene sets that are associated with a trajectory from planktonic to biofilm growth. BaSSSh-seq …

Revisiting The Motivated Denial Of Mind To Animals Used For Food: Replication Registered Report Of Bastian Et Al. (2012), Tyler P. Jacobs, M. Wang, S. Leach, H. L. Siu, M. Khanna, K. W. Chan, H. T. Chau, K. Y. Y. Tam, G. Feldman

Psychology Faculty Works

Bastian et al. (2012) argued that the meat paradox—caring for animals yet eating them—creates a tension between people’s moral standards (caring for animals) and their behavior (eating them) that can be resolved via mechanisms of motivated moral disengagement. One disengagement mechanism that is thought to play a central role is the denial of food-animal minds and therefore their status as moral patients. This idea has garnered substantial interest and has framed much of the psychological approach to meat consumption. We subjected Studies 1 and 2 of Bastian et al. (2012) to high-powered direct replications and found support for the target …

Phosphorus-Independent Role Of Fgf23 In Erythropoiesis And Iron Homeostasis., Min Young Park, Rafiou Agoro, Stanislovas S Jankauskas, Carole Le Henaff, Despina Sitara

Faculty Research 2024

A number of studies have reported an association between phosphorus, red blood cell (RBC) production, and iron metabolism. However, it is difficult to distinguish whether the effect of phosphorus is direct or through the actions of FGF23, and it is not clear whether phosphorus is positively or negatively associated with RBC production. In the present study, we investigated the effects of a) increased phosphorus load and b) phosphorus deficiency on erythropoiesis and iron metabolism in association with FGF23. Mice were fed either a 1.2% or 1.65% phosphorus diet and compared to mice fed a control diet containing 0.6% of phosphorus. …

Control Of Hippocampal Synaptic Plasticity By Microglia-Dendrite Interactions Depends On Genetic Context In Mouse Models Of Alzheimer's Disease., Sarah E Heuer, Kelly J Keezer, Amanda A Hewes, Kristen D. Onos, Kourtney Graham, Gareth R Howell, Erik B Bloss

Faculty Research 2024

INTRODUCTION: Human data suggest susceptibility and resilience to features of Alzheimer's disease (AD) such as microglia activation and synaptic dysfunction are under genetic control. However, causal relationships between these processes, and how genomic diversity modulates them remain systemically underexplored in mouse models.

METHODS: AD-vulnerable hippocampal neurons were virally labeled in inbred (C57BL/6J) and wild-derived (PWK/PhJ) APP/PS1 and wild-type mice, and brain microglia depleted from 4 to 8 months of age. Dendrites were assessed for synapse plasticity changes by evaluating spine densities and morphologies.

RESULTS: In C57BL/6J, microglia depletion blocked amyloid-induced synaptic density and morphology changes. At a finer scale, synaptic …