Digital Commons Network^™

Erk-Mediated Phosphorylation Of Yap Defines A Noncanonical Fgf Signaling Mechanism In Stem Cells, Xiaolei Zhao, Shannon Erhardt, Li Tang, Xiaotong Chen, Stephen M Farmer, Zixiu Cheng, Wen Chen, Ella Ziyuan Lu, Kihan Sung, Chang-Ru Tsai, Mingjie Zheng, Sheng Zhang, Yang Liu, Jianxin Wang, Min Li, James F Martin, Jun Wang

Faculty, Staff and Student Publications

While Fgf and Hippo-Yap signaling are fundamental for proper development, homeostasis, and disease, their crosstalk remains largely unknown. Here, we identified that Yap and Taz, canonical Hippo effectors, function as noncanonical effectors of Fgf signaling to maintain the proper function of neural crest (NC) lineages. NC cells are a multipotent stem cell population during vertebrate embryogenesis that contribute to numerous structures and diverse cell lineages, including craniofacial and cardiac tissues, neurons, and suture mesenchymal cells (SMCs), a specified cell population required for cranial bone growth and repair. We observed that activation of Fgf signaling in NC cells and NC-derived SMCs …

Chemotherapeutic Induction Of Cytosolic Single-Stranded Dna Accumulation Sensitizes Triple-Negative Breast Cancer To Immunotherapy, Yong Du, Li Yang, Hui Dai, Jianli Zhou, Zhicheng Zhou, Ruoxi Yuan, Rui Ye, Anh Thai Quynh Nguyen, Kishor Bhatia, Shiaw-Yih Lin

Faculty, Staff and Students Publications

Background: Despite the widespread adoption of chemoimmunotherapy in triple-negative breast cancer (TNBC), the mechanisms by which cytotoxic chemotherapy engages antitumor immunity remain poorly defined. Identifying tumor-intrinsic immunogenic programs that predict and enhance responsiveness to immune checkpoint blockade (ICB) is therefore of critical clinical importance.

Methods: Transcriptomic signatures of TREX1 deficiency were generated from CRISPR-engineered TNBC models and applied to multiple independent TNBC cohorts treated with chemoimmunotherapy. Cytosolic single-stranded DNA (ssDNA) accumulation was quantified using a flow cytometry-based assay to functionally screen chemotherapeutic agents. Immune activation and therapeutic efficacy were evaluated using in vitro assays, syngeneic mouse tumor models, flow cytometry, …

Folr1-Targeted Actinium-225-Based Alpha-Particle Therapy Eliminates Ovarian Cancer, Neetu Singh, Esther Need, Ayden Berndt, Matthew Goff, Lydia J. Wilson, Firas Mourtada, Feng Guo, Tara Mastren, Taslim Al-Hilal, Anil K. Sood, Amit Maity, Scott C. Miller, Satoshi Minoshima, Shreya Goel, Sixiang Shi

Department of Radiation Oncology Faculty Papers

Despite the advancement in therapies, ovarian cancer treatment is challenging because of poor prognosis and high relapse associated with acquired resistance. Emerging targeted alpha particles, particularly actinium-225 (225Ac), for treating refractory cancers have opened avenues for improved therapeutic options. Here, we describe a successful example of folate receptor 1 (FOLR1)–targeted 225Ac alpha-particle therapy for treatment of ovarian cancer. Longitudinal positron emission tomography imaging demonstrated high tumor-specific uptake of αFOLR1 (anti-FOLR1 antibody) in SKOV3 xenografts. FOLR1-targeted 225Ac demonstrated high therapeutic efficacy, achieving marked tumor regression, 80% survival, and 40% complete tumor elimination. The therapy resulted in tumor-specific double-stranded DNA damage, and …

Microglial Swell1 Deficiency Drives Male-Specific Seizure Vulnerability But Paradoxical Neuroprotection Through Impaired Phagocytosis, Abhijeet S Barath, Aastha Dheer, Laura Montier, Mekenzie M Peshoff, Emily Dale, Flavia Goche, Thanh Thanh Le Nguyen, Mastura Akter, Fangfang Qi, Dimitrios Kleidonas, Lauren Harris, Sarah A Jewanee, Anthony D Umpierre, Dale B Bosco, Koichiro Haruwaka, Rajan Sah, Long-Jun Wu, Rongzhuo Hua, Tejaswani Datla

The Brown Foundation: Institute of Molecular Medicine

The discovery of genes encoding the volume-regulated anion channel (VRAC) has enabled detailed exploration of its cell type-specific roles in the brain. LRRC8A (SWELL1) is the essential VRAC subunit. We observed seizure-induced, subunit-specific changes in microglial VRAC expression and investigated its function using conditional KO (cKO) of LRRC8A in microglia. SWELL1 cKO mice exhibited a male-specific increase in kainate-induced seizure severity, yet showed paradoxical neuroprotection against seizure-associated neuronal loss. Mechanistically, SWELL1 deletion led to a cell-autonomous reduction in microglial density and decreased release of VRAC-permeable neuroactive metabolites, including taurine, GABA, and glutamate in culture. Additionally, impaired phagocytic kinetics and reduced …

Neddylation Maintains Oocyte Quality By Stabilizing Mitochondrial Transcription, Avery A Ahmed, Tessa E Steenwinkel, Bethany K Patton, Peixin Jiang, Matthew D Meyer, Jaspreet K Rishi, Mei Leng, Alexander B Saltzman, Elizabeth S Anaya, Momal Sharif, Laurie J Mckenzie, Laura Detti, Anna Malovannaya, Sean M Hartig, Stephanie A Pangas

Faculty, Staff and Students Publications

Age-related decline in oocyte quality increases the risk of infertility, miscarriage, and birth defects. Mitochondrial dysfunction is a key contributor to this decline. Here, we report that oocyte-specific deletion of Uba3, which encodes the catalytic subunit of the E1 NEDDylation-activating complex, causes sterility in mice. Fully grown, germinal vesicle–stage Uba3 conditional knockout oocytes exhibit mitochondrial dysfunction, including elevated reactive oxygen species, impaired oxidative phosphorylation, and depletion of mitochondrially encoded RNA transcripts. Proteomic analysis identified alterations in mitochondrial-associated proteins, including enrichment of mitochondrial matrix and respiratory chain components and reduced abundance of electron transport chain complexes. These defects were associated …

D-Methionine Improves Spatial Navigation And Attenuates Oxidative Stress And Amyloid Pathology In A Sex-Specific Manner., Mackenzie R Peck, Jenelle E Chapman, Tiarra Hill, Kathleen Quinn, Erol D Ikiz, Angel Lopez, Erin R Hascup, Chilman Bae, Kevin N Hascup

Articles

Background

Oxidative stress and maladaptive neuroimmune activation contribute to cognitive decline in Alzheimer's disease (AD) and represent therapeutic targets beyond amyloid-centered approaches.

Objective

To determine whether oral D-methionine (D-Met), a redox-active amino acid, reduces amyloid pathology and lipid peroxidation and confers disease-modifying benefits in AD models.

Methods

Male and female APP/PS1 and APP^NL−Fmice with advanced AD pathology received oral D-Met or vehicle. Behavioral assessments included locomotor activity and hippocampal-dependent spatial learning and memory. Amyloid burden, lipid peroxidation, peripheral metabolic, and inflammatory markers, and hippocampal microglial phenotypes were evaluated.

Results

D-Met did not alter locomotor or exploratory behavior but …

Hp1bp3 Loss Links Chromatin Reorganization To Metabolic Vulnerability In Glioma, Brittney Lozzi, Taylor A Gatesman, Pushan Dasgupta, Debosmita Sardar, Yeunjung Ko, Chenyu Mao, Hsiao-Chi Chen, Rachel N Curry, Dongjoo Choi, Carrie A Mohila, Melissa L Bondy, Ganesh Rao, Marco Gallo, Sameer Agnihotri, Benjamin Deneen

Duncan NRI Faculty and Staff Publications

High-grade gliomas (HGGs) are aggressive brain tumors with poor prognosis, driven in part by metabolic and epigenetic adaptations. Methionine metabolism supports HGG growth by supplying S-adenosylmethionine for methylation reactions, yet how nutrient availability influences chromatin organization in HGG remains incompletely understood. Using an immunocompetent mouse model of HGG, we found that dietary methionine restriction reduced tumor proliferation, extended survival, and induced partial nuclear inversion. We identified Hp1bp3 as a key regulator of tumor growth that functions by interacting with nuclear tethering proteins to mediate chromatin reorganization. Loss of Hp1bp3 results in the upregulation of histone demethylases leading to selective depletion …

Macropinocytosis Inhibition Attenuates Profibrotic Responses In Lung Fibroblasts And Pulmonary Fibrosis Models, Ivan O Rosas, Aaron K Mcdowell-Sanchez, Santiago Sanchez, Juan D Cala-Garcia, Alan R Waich Cohen, Elisa Ruiz-Echartea, Scott A Ochsner, Daniel C Kraushaar, Lindsay J Celada, Dandan Sun, Francesca Polverino, Cristian Coarfa, Neil J Mckenna, Konstantin Tsoyi

Faculty, Staff and Students Publications

Idiopathic pulmonary fibrosis (IPF) is a devastating chronic lung disorder with limited treatment options. Macropinocytosis is one of the key cellular processes involved in nutrient consumption from the extracellular environment under stress conditions. Here, we studied the role of macropinocytosis in experimental pulmonary fibrosis models. We found that macropinocytosis is increased in human lung fibroblasts (HLFs) derived from patients with IPF. The inhibition of macropinocytosis with 5-(n-ethyl-n-isopropyl)-amiloride (EIPA) inhibited profibrotic responses in IPF-derived and TGF-β1-stimulated HLFs and reduced pulmonary fibrosis in bleomycin-injured (Bleo-injured) mice. EIPA exerted its antifibrotic effects by regulating amino acid uptake, mammalian target of rapamycin complex 1 …

Trans-Regulation Of Heterochromatin Underlies Genetic Variation In 3d Genome Contacts In Mouse Embryonic Stem Cells., Haley J Fortin, Anna Z Struba, Arad Bustan, Christopher L. Baker

Faculty Research 2026

BACKGROUND: Genetic variation drives phenotypic diversity and disease susceptibility. Trans-acting genetic variation coordinates genome-wide chromatin changes, yet the molecular mechanisms underlying this distal regulation remain unclear. Here, we use the power of mouse genetics to investigate how genetic variation at trans-acting loci regulates three-dimensional (3D) chromatin interactions.

RESULTS: Using HiChIP to map chromatin contacts among regulatory elements in C57BL/6J and DBA/2J embryonic stem cells (ESCs), we identify 4,962 strain-differential interactions. Of these, 71% overlap chromatin accessibility quantitative trait loci (QTL), establishing that interaction variation is predominantly heritable. These differential interactions show coordinated changes in chromatin state and gene expression, with …

Single-Nucleus Profiling Reveals A Core Disease Signature And Cell Type-Specific Vulnerabilities In Early Rett Syndrome, Yan Li, Ashley G Anderson, Guantong Qi, Sih-Rong Wu, Jean-Pierre Revelli, Hu Chen, Zhandong Liu, Huda Y Zoghbi

Faculty, Staff and Students Publications

Rett syndrome (RTT) is an X-linked neurological disorder caused by MECP2 mutations, creating distinct cellular environments in females (mosaic) versus males (nonmosaic). Despite female patients representing most cases, how mosaicism contributes molecularly to RTT pathogenesis, particularly in presymptomatic stages, remains poorly understood. To address this question, we profiled hippocampal transcriptomes of young female and male RTT mice using bulk and single-nucleus RNA sequencing. We identified a core disease signature of consistently dysregulated genes only in MeCP2− cells across RTT models. Moreover, we uncovered non–cell autonomous effects exclusively in female MeCP2+ excitatory neurons, suggesting that these circuits are more vulnerable early …

In Vivo Orf Overexpression Screening Identifies Ccn4 As A Regulator Of Glioblastoma Growth Validated Across Multiple Models, Pushan Dasgupta

Faculty, Staff and Students Publications

Despite current multimodal therapies for glioblastoma (GBM), its prognosis remains grim. Thus, a tremendous need exists to identify new genetic drivers that may serve as potential therapeutic targets in glioblastoma (GBM). We describe an in vivo overexpression screening strategy to identify drivers of glioblastoma where we have leveraged TCGA datasets to conduct a functional genomics screen of prioritized open reading frames (ORFs) that are overexpressed and/or amplified in GBM. To interrogate these potential drivers within a more relevant physiological context, the screening was accomplished in vivo in an orthotopic patient-derived glioma stem-like cell (GSC) model. Among 5 positive "hits" from …

Notch1 Acts As A Tumor Suppressor That Induces Early Differentiation In Head And Neck Cancer, Chenfei Huang, Shhyam Moorthy, Qiuli Li, Kazi M Ahmed, Kalil Saab, Defeng Deng, Jiping Wang, Xiayu Rao, Jiexin Zhang, Yuanxin Xi, Jing Wang, Zhiyi Liu, Noriaki Tanaka, David A Wheeler, Eve Shinbrot, Rami Saade, Curtis R Pickering, Tong-Xin Xie, Adel K El-Naggar, Abdullah A Osman, Kunal Rai, Patrick A Zweidler-Mckay, John V Heymach, Lauren A Byers, Faye M Johnson, Vlad C Sandulache, Jeffrey N Myers, Pedram Yadollahi, Mitchell J Frederick

Faculty, Staff and Students Publications

Inactivating NOTCH1 mutations in head and neck squamous cell carcinoma (HNSCC) were described over a decade ago, suggesting a tumor suppressor function - unlike its oncogenic role in other tumors. Today, much debate persists regarding a putative oncogenic role in HNSCC as well, with reports that NOTCH1 signaling drives tumor growth and a cancer stem cell (CSC) phenotype. In this work, comprehensive experiments unequivocally demonstrate that NOTCH1 is a tumor suppressor in HNSCC regardless of mutation or activation status and that it reduces CSC frequency. We developed a signature of NOTCH1 activation showing the pathway is associated with very early …

Monoclonal Antibodies Targeting Pcdh7 Inhibit Tumor Growth And Enhance Immune Responses In Kras-Mutant Non-Small Cell Lung Cancer, Nicole Novaresi, Poorva Ghosh, Shayna Thomas-Jardin, Hui Deng, Xuejun Fan, Zhiqiang Ku, Wei Xiong, Xiaorong Zhou, Jingfei Zhu, Huiyu Li, Mahesh S Padanad, Bethany Smith, Chul Ahn, John D Minna, Zhiqiang An, Ningyan Zhang, Kathryn A O'Donnell

The Brown Foundation: Institute of Molecular Medicine

We identified an important oncogenic role for protocadherin 7 (PCDH7), a cell surface protein frequently overexpressed in lung adenocarcinoma and associated with poor clinical outcome. Pcdh7 depletion reduces tumor burden and prolongs survival in KrasLSL-G12D; Tp53fl/fl mice. These findings nominate this cell surface protein as an actionable therapeutic target and highlight the therapeutic potential of PCDH7 inhibition for non–small cell lung cancer. We report the development and characterization of high-affinity anti-PCDH7 monoclonal antibodies (mAbs) that inhibit downstream mitogen-activated protein kinase (MAPK) pathway activation and suppress tumor growth in multiple mutant KRAS–driven models. A lead mAb (mAb7) sensitized tumors …

Amc-F1 Regulates Mitochondria-Autophagy Crosstalk Independent Of Nutrient Stress, Yuqin Wang, Raksha K Rao, Trung Vu, Ayano Sekine, Zhengmei Mao, Nami Mccarty

The Brown Foundation: Institute of Molecular Medicine

Mitochondria and autophagy are fundamental yet distinct regulators of cellular homeostasis. Here, we identify AMC-F1 (Autophagy-Mitochondria Coupling Factor 1; formerly TRIM44) as a central integrator of mitochondrial bioenergetics and autophagy. Using Amcf1 knockout and knock-in mouse models, we demonstrate that AMC-F1 bidirectionally regulates these pathways: its loss reduces mitochondrial respiration and autophagic flux, whereas its overexpression promotes mitochondrial elongation and increases autophagy independently of nutrient stress. Transcriptomic analyses reveal AMC-F1-dependent regulation of mitochondrial biogenesis programs that engage autophagy, involving mitochondrial respiratory chain complex genes under basal conditions and mitochondrial organization factors under starvation-induced autophagy. Although dispensable under homeostasis, this coupling …

Cytosine Base Editing Of Lpa In Transgenic Mice Averts Large Deletions, Marcel A Chuecos, So Hyun Park, Madhvi M Bhakta, Usosa Too-Chiobi, Daniel Betancourth, Mingming Cao, Marco De Giorgi, Christopher J Walkey, Anjana Tiwari, Biana Godin, Julia M Assini, Donna J Palmer, Philip Ng, Michael B Boffa, Marlys L Koschinsky, Gang Bao, William R Lagor

Faculty, Staff and Students Publications

Lipoprotein(a) (Lp(a)) is a genetically determined causal risk factor for cardiovascular disease, with approximately 20% of the population exhibiting elevated levels. While there are promising drugs in development, there are currently no approved therapies specifically designed to lower Lp(a) levels. For high-risk individuals with extreme levels of Lp(a), liver-directed genome editing could be an effective one-time solution. Genome editing approaches such as CRISPR and TALENs can reduce Lp(a) in LPA-transgenic mouse models, but they frequently induce large and potentially harmful genomic deletions. Here, we report the first application of TadA-derived cytosine base editing (CBE), delivered via helper-dependent adenovirus (HDAdV) and …

Loss Of Mct1 Mediated Lactate Uptake Causes Delayed Endplate Maturation And Intervertebral Disc Degeneration, Maria Tsingas, Konstantinos Tsingas, Mei Smyers, Wujuan Zhang, Aaron R. Goldman, Eulisa Lawrence, John A. Collins, Makarand V. Risbud

Department of Orthopaedic Surgery Faculty Papers

During skeletal growth, it is thought that the lactate secreted by the glycolytic nucleus pulposus (NP) cells exits the intervertebral disc into circulation via endplates. Our current studies challenge this long-held notion. Mice with early postnatal, endplate, and annulus fibrosus-specific deletion of lactate importer, MCT1, exhibited disc degeneration characterized by NP cell loss and pronounced endplate structural changes. Using metabolic and transcriptomic approaches, we demonstrate that MCT1 loss inhibits endplate chondrocyte differentiation and that lactate serves both as a crucial TCA metabolite and promotes protein and histone lactylation and gene expression. These findings suggest that during skeletal growth, NP-derived lactate …

An Obligatory Role For Agrp Neurons In Maintaining Body Temperature During Time-Restricted Feeding, Cunjin Su, Jing Cai, Yuanzhong Xu, Benjamin R Arenkiel, Qingchun Tong

The Brown Foundation: Institute of Molecular Medicine

Homeotherms maintain a steady body temperature through thermoregulation, a process critical for survival during fasting, in which the brain has to defend energy-costly body temperature while reducing energy expenditure to conserve energy reserve; however, the neural basis for defending body temperature remains unclear. Here, we demonstrated that AgRP neuron lesion led to lethality during time-restricted feeding on chow but not on HFD, and caused no obvious impact on HFD-induced obesity or obesity-reducing responses to glucagon-like peptide-1 receptor agonism. The lesion disrupted adaptive feeding behaviors during time-restricted feeding and reduced motivational feeding on chow. Notably, the lethality was caused by hypothermia …

Generation And Characterization Of Twist1 Acetyl-Mimic And Acetyl-Deficient Mouse Models, Mary Elmeniawi, Xiaobin Yu, Samuel Wen, Gunjan A Bhatia, Lan Liao, Jianming Xu, Walid D Fakhouri

Faculty, Staff and Students Publications

TWIST1 encodes a highly conserved basic helix–loop–helix transcription factor essential for embryonic development from Drosophila to humans. TWIST1 activity is regulated by post‐translational modifications, including phosphorylation during development and cancer metastasis. Recent cancer studies identified acetylation of lysines K73 and K76 as a novel regulatory modification that shifts TWIST1 from a repressive to an activating state during epithelial‐to‐mesenchymal transition (EMT). However, the developmental and in vivo functions of TWIST1 acetylation remain unknown. To investigate the physiological role, we generated the first acetyl‐deficient Twist1 K73,76R K73,76R and acetyl‐mimic Twist1 K73,76Q K73,76Q mouse models using CRISPR/Cas9‐mediated genome editing. Targeted sequencing confirmed substitutions, …

Development Of A Second-Generation Rarα Selective Antagonist As An Orally Bioavailable, Effective, Safe, And Reversible Male Contraceptive, Rui Shi, Kristen John, Xuan Qin, Ehfazul Haque, Taimeng Liang, Narsihmulu Cheryala, Feng Li, Henry L Wong, Gunda I Georg

Faculty, Staff and Students Publications

We report the design and SAR studies of benzopyran-, benzofuran-, and benzothiophene-derived inhibitors of the retinoic acid receptor alpha (RARα) for male contraception. SAR studies identified critical features influencing activity, such as the optimal positioning of antagonism moieties and substituents, leading to the discovery of (S)-4-(5-(2,8-dimethyl-5-(p-tolyl)-2H-chromen-3-yl)-1H-pyrrol-2-yl)­benzoic acid (compound 23). Compound 23 is a highly potent RARα inhibitor (IC50 = 0.051 nM) with excellent selectivity (>1650-fold over RARβ and >1960-fold over RARγ) and ADMET properties. Compound 23 is orally bioavailable and reduces sperm counts in mice for a full male contraceptive effect …

Unbiased Niche Labeling Maps Immune-Excluded Niche In Bone Metastasis, Zhan Xu, Fengshuo Liu, Yunfeng Ding, Tianhong Pan, Yi-Hsuan Wu, Yujiao Han, Jun Liu, Igor L Bado, Weijie Zhang, Ling Wu, Yang Gao, Xiaoxin Hao, Liqun Yu, Xuan Li, David G Edwards, Hilda L Chan, Sergio Aguirre, Michael Warren Dieffenbach, Elina Chen, Siyue Wang, Yichao Shen, Dane Hoffman, Luis Becerra Dominguez, Charlotte Helena Rivas, Xiang Chen, Hai Wang, Yibin Kang, Zbigniew Gugala, Robert L Satcher, Xiang H-F Zhang

Faculty, Staff and Students Publications

Metastatic cancer cell fate is shaped by the local microenvironment niches. To unbiasedly define the cellular and molecular features of metastatic niches, we developed sortase A-based microenvironment niche tagging (SAMENT), which selectively labels cells encountered by cancer cells during metastasis. Applying SAMENT across multiple cancer models and target organs revealed shared niche features, including macrophage enrichment and T cell depletion, alongside marked organ-specific phenotype heterogeneity in niche macrophages. In bone, metastatic niches are enriched for macrophages expressing estrogen receptor alpha (ERα) with active ERα signaling. Conditional deletion of Esr1 in macrophages significantly impaired bone colonization by enabling T cell infiltration. …

Acidic Extracellular Ph-Induced Pth Secretion In Male Mouse Parathyroids Is Ogr1-Dependent, Yanmei Yang, Mengcun Chen, Mingshu Cui, Elisabeth Lashbrooks, Bin Wang

Center for Translational Medicine Faculty Papers

The role of extracellular acidity in regulating PTH secretion in cultured mouse parathyroid glands (PTGs) has not been studied to date, largely because of the technical difficulty of isolating mouse PTGs. We hypothesized that acidic extracellular pH directly stimulates PTH secretion through activation of a proton-sensing receptor, specifically ovarian cancer G protein-coupled receptor 1 (OGR1, also known as GPR68). To test this, we developed a method to reliably identify and isolate PTGs from male mice by administering 5-aminolevulinic acid, which induced selective fluorescence in these glands. Using this model, we demonstrate that acidic extracellular pH significantly stimulates PTH secretion in …

Acidic Extracellular Ph-Induced Pth Secretion In Male Mouse Parathyroids Is Ogr1-Dependent, Yanmei Yang, Mengcun Chen, Mingshu Cui, Elisabeth Lashbrooks, Bin Wang

Center for Translational Medicine Faculty Papers

The role of extracellular acidity in regulating PTH secretion in cultured mouse parathyroid glands (PTGs) has not been studied to date, largely because of the technical difficulty of isolating mouse PTGs. We hypothesized that acidic extracellular pH directly stimulates PTH secretion through activation of a proton-sensing receptor, specifically ovarian cancer G protein-coupled receptor 1 (OGR1, also known as GPR68). To test this, we developed a method to reliably identify and isolate PTGs from male mice by administering 5-aminolevulinic acid, which induced selective fluorescence in these glands. Using this model, we demonstrate that acidic extracellular pH significantly stimulates PTH secretion in …

Movement-Stabilized Three-Dimensional Optical Recordings Of Membrane Potential Changes And Calcium Dynamics In Hippocampal Ca1 Dendrites, Kevin C Gonzalez, Satoshi Terada, Asako Noguchi, George N Zakka, Cliodhna O'Toole, Giuliana Bilbao, Luke Reynolds, Anna Jász, Borbála Kertész, Zoltán Szadai, Alissa Shen, François St-Pierre, Franck Polleux, Attila Losonczy, Balázs Rózsa

Faculty, Staff and Students Publications

Local dendritic computations are thought to critically influence neuronal signaling and plasticity yet remain largely unexplored in vivo due to challenges in stably imaging small structures at ultrafast timescales. We developed a 3D real-time motion correction platform for movement-stabilized, ultrafast two-photon voltage imaging. By co-labeling CA1 pyramidal neurons with voltage and calcium indicators, we simultaneously measured somato-dendritic and electro-calcium coupling at multiple dendritic sites. We characterized isolated dendritic spikes and distance-dependent backpropagation of naturally occurring and photostimulation-evoked bursts and single spikes. We found that bursts backpropagated more reliably than single spikes, validated that somato-dendritic coupling decreases with distance from soma, …

Crystal Structure Of Mouse Dxo In Complex With The Udp-N-Acetylglucosamine Cap And Molecular Mechanism For The Decapping Reactions, Najeeb Ullah, Selom K. Doamekpor, Liang Tong

Department of Biochemistry and Molecular Biology Faculty Papers

Noncanonical metabolite 5' caps have recently been identified on RNAs, and the DXO/Rai1 family of enzymes can remove these caps in eukaryotes. While the binding modes of NAD, FAD and dephospho-CoA (dpCoA) caps in the active site of mouse DXO have been determined, how DXO recognizes the UDP-glucose (UDP-Glc) and UDP-N-acetylglucosamine (UDP-GlcNAc) caps is not known. In addition, the molecular mechanism by which DXO catalyzes the decapping reactions is still poorly understood, especially the location of the water/hydroxide that attacks the scissile phosphate to initiate the decapping. Here we report the crystal structure of mouse DXO in complex with UDP-GlcNAc …

P300/Cbp Inhibition With Inobrodib In Combination With Gilteritinib And Venetoclax Targets Leukemia Stem Cells In Epigenetic Mutant Aml, Melanie L. Goetz, Jennifer S. Romer-Seibert, Amanda M. Versace, Scott Kogan, Chetan Jeurkar, Robert L. Bowman, Nigel Brooks, Kris Frese, Sara E. Meyer

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Acute myeloid leukemia (AML) is a fatal blood cancer with cytotoxic chemotherapy offering at best 25% 5-year survival. While targeted BCL2 and FLT3 inhibitors venetoclax and gilteritinib are used upfront in the treatment of a subset of adult patients with AML and help to extend the survival of some patients, a curative treatment combination with minimal side effects has yet to be discovered. We find that use of the dual histone acetyltransferase p300/CBP bromodomain inhibitor CCS1477 (inobrodib), together with venetoclax and gilteritinib, virtually eliminates leukemia stem cells in an aggressive preclinical model of DNMT3A/FLT3-mutant AML by impairing pro-oncogenic survival and …

Cardiac Hdac3 Disruption Contributes To Hdac Inhibitor-Induced Qt Prolongation, Jiao Lu, Christopher Ward, Sichong Qian, Lilei Zhang, Jiang Chang, Zheng Sun

Faculty, Staff and Students Publications

Histone deacetylase (HDAC) inhibitors are approved for cancer treatment and are being investigated for a wide range of other diseases. Despite their therapeutic promise, clinical studies have reported cardiac side effects, particularly electrocardiogram (EKG) abnormalities, with QT interval prolongation being one of the most consistently reported findings. The mechanisms underlying these cardiac effects remain unclear. In this study, we investigated the role of HDAC3 in cardiac electrophysiology. We found that postnatal depletion of cardiac HDAC3 in mice caused QT interval prolongation, recapitulating the EKG abnormalities reported with HDAC inhibitor use. Adult-onset inducible depletion of cardiac HDAC3 induced additional EKG abnormalities, …

Selective And Differential Roles Of Pvhcrh Neurotransmitters In Diet-Induced Obesity In Mice, Zhiying Jiang, Yuhan Cao, Michelle He, Cunjin Su, Runzhou Yang, Maojie Yang, Jing Cai, Hongli Li, Yuanzhong Xu, Shi-Bin Li, Hiroshi Yamaguchi, Luis De Lecea, Benjamin R Arenkiel, Qingchun Tong

The Brown Foundation: Institute of Molecular Medicine

Stress and diet are known to synergistically promote risks of obesity but the underlying neural basis remains elusive. Corticotropin-releasing hormone neurons in the paraventricular hypothalamus (PVHCRH) are stress responsive and release both CRH and glutamate. Here we generated a mouse model with gain or loss of release in CRH or glutamate from PVHCRH neurons. While these models showed no changes in body weight when fed chow, they exhibited contrasting effects when fed high-fat high-caloric diets (HFD). Whereas disrupting glutamate release from PVHCRH neurons led to diet-induced obesity (DIO), that of CRH caused no impact. Conversely, augmented CRH release led to …

Volume Electron Microscopy Reveals Heterogeneity Of The Hemostatic Response In Veins And Arteries, Maurizio Tomaiuolo, Meghan E. Roberts, Jenna R. Severa, Christopher D. Mansi, Brenna B. Y. Mathers, Anna Mannix, Trace A Christensen, Lawrence F Brass, Talid Sinno, Timothy J. Stalker

Cardeza Foundation for Hematologic Research

Intravital imaging studies have provided insights into the spatial and temporal variations of platelet activation and thrombin generation that occur during hemostasis; however, these studies are generally limited to small vessels due to the practical limitations of imaging in thicker tissues. Recent advances in cleared tissue fluorescence imaging as well as volume electron microscopy (vEM) coupled with machine learning-based image segmentation provide an opportunity for analysis of the 3-dimensional structure of complex tissues. We utilized these technologies to examine hemostatic plugs from murine jugular veins and carotid arteries to investigate the spatial distribution of platelet activation and biochemical responses in …

Progressive Cardiac Phenotypes And Reduced Reversibility From Long-Term Cugexp Rna Expression In A Dm1 Mouse Model, Rong-Chi Hu, Mohammadreza Tabary, Xander Ht Wehrens, Thomas A Cooper

Faculty, Staff and Students Publications

Myotonic dystrophy type 1 (DM1) is caused by an expanded CTG repeat in the DMPK gene, resulting in mutant transcripts that form expanded CUG (CUGexp) RNA foci and sequester muscleblind-like (MBNL) RNA-binding proteins. DM1 is multisystemic, with progressive worsening of disease manifestations in affected tissues. Disease progression is attributed to somatic expansion of the CTG repeats with age, resulting in production of CUGexp RNA with enhanced intrinsic toxicity due to increased MBNL sequestration. To determine the degree to which cardiac disease progression can occur independently of repeat expansion, we used a transgenic DM1 mouse model with inducible heart-specific expression of …

Tunable Tripcides Suppress Virulence Factor Secretion During Staphylococcus Aureus Infection And Kill Dormant Cells, Hasan Tükenmez, Taylor M Nye, Suzanne Hickerson, Chloe L P Obernuefemann, Jerome S Pinkner, Karen W Dodson, Michael G Caparon, Scott J Hultgren, Et Al.

2020-Current year OA Pubs

Antimicrobial resistance (AMR) in common bacterial pathogens, including methicillin-resistant