Digital Commons Network^™

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 …

Chromatin Insulators Homie And Nhomie Can Interact With Distant Copies Either Together Or Separately, With Distinct Outcomes For Enhancer-Promoter Interactions, Miki Fujioka, Wenfan Ke, Paul Schedl, James B. Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

Chromatin insulators, a.k.a. boundary elements, separate regions of the chromosome with distinct chromatin characteristics, including distinct histone modifications. This activity affects gene expression by allowing chromatin domains to be stably regulated and maintained. Insulators also block enhancer-promoter interactions and, somewhat paradoxically, facilitate other interactions, particularly when they stitch together distant regions of the chromosome by pairing with specific partners. Here we explore how long-range interactions facilitated by insulator pairing are affected by the presence of two potentially competing partners. Our results show that when two partners are present, they can reduce each other's effects on distant gene expression, suggesting that …

Transgenic Hookworm Secretes Anti-Tetrodotoxin Human Single Chain Antibody, Kumar Sachin Singh, Suman Bharti, Bruce A Rosa, Mahdiyeh Bigham, Samuel C Uzoechi, Young-Jun Choi, John C Martin, Danielle Kemper, Slavica Pavlovic Djuranovic, Darren A Pickering, Rachael Ryan, Bethany K Bracken, Maria Elena Bottazzi, Eric C Carnes, Wannaporn Ittiprasert, Matthew Moyle, Paul J Brindley, Alex Loukas, Sergej Djuranovic, Makedonka Mitreva

Faculty, Staff and Students Publications

Biologics, protein- and peptide-based drugs derived from living organisms or cell lines have emerged as effective therapies across a broad range of indications. However, parenteral administration and the need for frequent dosing increase costs and limit compliance, creating an urgent need for innovative platforms capable of continuously, safely, and efficiently delivering sustained biologics in situ within the host. Here, we describe a bioengineered hookworm platform to manufacture and deliver biologic therapeutics in vivo. As proof of concept, we engineer the Ancylostoma ceylanicum secretome by inserting a human single-chain variable fragment antibody (s16-HuScFv) into its genome. Transgene expression does not perturb …

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 …

Systems Genetic Dissection Of Brain Gene Expression Reveals Excitotoxic Mechanisms Of Alzheimer’S Disease, Pinghan Zhao, Omar El Fadel, Anh Le, Carl Grant Mangleburg, Justin Dhindsa, Timothy Wu, Jinghan Zhao, Meichen Huang, Bismark Amoh, Aditi Sai Marella, Yarong Li, Nicholas T Seyfried, Allan I Levey, Zhandong Liu, Ismael Al-Ramahi, Juan Botas, Joshua M Shulman

Faculty, Staff and Students Publications

Gene expression changes likely mediate the impact of Alzheimer's disease (AD) neuropathology on cognition, but there are challenges to resolve the proximal causal pathways from postmortem brain transcriptome profiles which lack temporal resolution and are further confounded by mixed pathologies. Here, we functionally dissect 30 AD-associated human brain gene co-expression modules using fruit fly (Drosophila melanogaster) models. Integrating longitudinal RNA-sequencing and behavioral phenotyping, we interrogated the consequences of amyloid beta (Aβ) plaques, tau neurofibrillary tangles, and aging, highlighting hundreds of conserved, differentially expressed genes. To pinpoint causal modules and drivers, we manipulated 344 prioritized targets in vivo, identifying 141 modifiers …

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 …

Steroid Receptor Coactivators In Immunity – From Function To Emerging Translational Opportunities, Yosef Gilad, David M Lonard

Faculty, Staff and Students Publications

Steroid Receptor Coactivators (SRCs) comprise a family of three paralogous proteins. As transcriptional coactivators SRCs are essential for enabling the full transcriptional output of nuclear receptors (NRs). They regulate the transcriptional activity of nearly all NRs as well as a wide range of non-NR transcription factors. The central role of SRCs in gene regulation is reflected in their broad impact on major physiological and pathological processes, such as development, reproduction, metabolism, immunity and cancer. Although the major impact of SRCs on human health and disease established them as attractive therapeutic targets, their effective pharmacological targeting remained a challenge for nearly …

Structural Determinants Of Ligand Response Specificity In The Mast Cell Activating Gpcr, Mrgprx2, Abiodun Adefola R Adeosun, Melina A Agosto, Olivier Lichtarge, Theodore G Wensel

Faculty, Staff and Students Publications

The mast cell-specific G-protein-coupled receptor (GPCR) MRGPRX2 (Mas-Related G Protein-coupled Receptor X2) has roles in itch and pain, and it mediates clinically relevant allergy-like responses to a diverse assortment of drugs. The varied responses of individuals to MRGPRX2 agonists, leading to drug hypersensitivity reactions in some cases, suggests the presence of consequential variants in the population. However, genetic associations with drug responses are poorly understood. We used heterologously-expressed MRGPRX2 to investigate the effect of 18 naturally occurring non-synonymous single nucleotide polymorphisms on activation by representative compounds from several classes, including neuropeptides, opioid agonists, antibiotics, neuromuscular blocking agents, and polycationic aromatic …

Corneal Innervation Research At A Crossroads: A Tool-Driven Roadmap For The Future, Anna Matynia, Ian D Meng, Brian M Davis, Stephen C Pflugfelder, Anat Galor, Victor L Perez, Elizabeth R Felix, Pedram Hamrah, Pantelimon Rompolas, Raul E Ruiz-Lozano, Shamsuddin A Bhuiyan, Kaveh Moghbeli, Evangelia Semizoglou, William Renthal, Harinder Singh, Jishnu Das, Marcin Golczak, Mary Ann Stepp, Catherine W Morgans, Cintia S De Paiva, Carl Y Saab, Igor Spigelman, Rony R Sayegh, Tally M Largent-Milnes, Hao Wu, Wenqin Luo, Sreya Mitra, Heesuk Yoo, Sina Farsiu, Sejiro Littleton, Eden Jacob, Matthew T Mcpheeters, Maryse Lapierre-Landry, Jordan J Smith, Xi Wang, Roxana Florea, Made Airanthi K Widjaja-Adhi, Scott Holmes, Zane Zemborain, Kate E T Laise, Nicholas J Pondelis, Ki-Soo Jeong, Rui Chen, Michael W Jenkins, Vivian Lee, Eric A Moulton, Deborah S Jacobs, Sue A Aicher, Anthony J St Leger, Daniel R Saban

Faculty, Staff and Students Publications

Corneal innervation research has faced long-standing clinical challenges that only recent technological breakthroughs now make tractable. Advances in single-cell analysis, viral vectors, clinical imaging, and artificial intelligence provide integrated approaches for uncovering molecular mechanisms underlying functional outcomes and facilitating clinical applications. The National Eye Institute's U01-funded consortium on ocular surface innervation addresses major knowledge gaps in characterizing corneal-projecting neurons, understanding neuroimmune and epithelial interactions in the cornea, and translating animal model findings to human pathology. The unique properties of the cornea (transparent, avascular, and densely innervated) make it ideal for neurobiology research on peripheral and central sensory processing. Through a …

Cytosignal Detects Locations And Dynamics Of Ligand-Receptor Signaling At Cellular Resolution From Spatial Transcriptomic Data, Jialin Liu, Hiroaki Manabe, Weizhou Qian, Shion Orikasa, Javid Ghaemmaghami, Yichen Wang, Yichen Gu, Angel Ka Yan Chu, Gaurav Gadhvi, Yuxuan Song, Patrick Mcclinden, Vibha N Lama, Noriaki Ono, Joshua D Welch

Faculty, Staff and Student Publications

Cells communicate through ligand-receptor (LR) signaling interactions, but identifying when and where these interactions are active remains challenging. We developed CytoSignal to infer the locations and dynamics of cell-cell communication at cellular resolution from spatial transcriptomic data. Here we show that our cellular resolution, spatially resolved signaling scores enable several important analyses-identifying spatial gradients in signaling strength, quantifying the locations of contact-dependent and diffusible interactions, detecting signaling-associated genes and identifying differential signaling across multisample data. Additionally, we can predict the temporal dynamics of a signaling interaction at each spatial location. We experimentally validate our results in situ by proximity ligation …

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, …

Wayfindr: Investigating Feedback In Biological Pathways, Polina Bombina, Reginald L Mcgee Ii, Jake Reed, Zachary B Abrams, Lynne V Abruzzo, Kevin R Coombes

2020-Current year OA Pubs

Understanding biological pathways requires more than static diagrams. We present WayFindR, an R package that converts pathway data from WikiPathways and KEGG into graph structures using igraph, enabling computational analysis of regulatory features such as negative feedback loops. Rooted in control theory, negative feedback is essential for system stability, yet it is often underrepresented in curated pathway data. In this study, we systematically analyzed pathway information from both databases across multiple species and found that feedback loops-particularly negative ones-are rarely captured. This gap likely reflects both biological and technical challenges. Biologically, feedback mechanisms are inherently complex and often remain uncharted …

Role Of Households With Children In Community Spread Of Multidrug-Resistant Enterobacterales, St. Louis, Missouri, Usa, Barrett Breeze, Ahmed Babiker, Sreenivas Konda, Alaina L Robinson, Stefan J Green, Catherine C Babbs, Federico Cunha, Katherine Y Shen, India Shepherd Hammond, Stephanie A Fritz, Latania K Logan

2020-Current year OA Pubs

Community-acquired multidrug-resistant (MDR) Enterobacterales bacteria are an increasing public health concern, yet whether households play a role in community spread remains unclear. We investigated 150 households with children in St. Louis, Missouri, USA, for MDR Enterobacterales. We cultured swab specimens from household members and environmental surfaces for identification and antimicrobial susceptibility testing. We also performed whole-genome sequencing in the 53 (35%) households where >1 MDR Enterobacterales species were recovered. Enterobacter hormaechei predominated, followed by Klebsiella pneumoniae and Pantoea species. Whole-genome sequencing revealed closely related strains shared between persons and environmental surfaces, suggesting potential intra-household transmission. We identified >1 horizontal gene …

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. …

Mitochondria-Er Contact Sites (Mercs) In The Cell Cycle: Molecular Architecture And Functional Remodeling Across Cellular States, Eduardo Silva-Pavez, Bruno Torres-Gonzalez, Michelle Sotomayor, Benjamín Cartes-Saavedra, Dorian V. Ziegler, Yessia Hidalgo-Fadic, Ulises Ahumada-Castro

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondria–endoplasmic reticulum (ER) contact sites (MERCS) are nanoscopic, dynamic platforms integrating metabolism, signaling, and stress responses to regulate cell fate. These nanoscopic interfaces remodel continuously to meet the demands of proliferating, quiescent, and senescent cells. We synthesize evidence that MERCS actively coordinate local Ca2+ signaling, non-vesicular lipid transfer, and proteostasis to shape mitochondrial function and cellular homeostasis. We discuss how MERCS architecture changes across the cell cycle and during arrest, distinguishing adaptive from maladaptive remodeling, and consider therapeutic potential in aging and age-related disease.

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 …

The Feather Of The Quill: How Folklore Shapes Human Relationships With Wildlife, Taylor Breeanne Nelson

Master's Theses

This thesis examines how folklore and cultural phenomena shape human relationships with wildlife, arguing that the stories a society tells about animals are not merely reflective of its values but are constitutive of them. Drawing on narrative research methods sourced from literature and academic journals and interviews with academics, conservationists, and community members, this project examines the role of animal folklore.

I discuss how narratives around wildlife evolved alongside the development of the United States, arguing that the beginnings of mainstream American conservation not only displaced existing communities but also erased the sophisticated human-animal relationships their traditions had long sustained. …

O-Glcnacylation As A Metabolic Integrator In Cardiovascular Physiology And Disease, Saima Shakil Malik, Xinchun Pi, Liang Xie

Faculty, Staff and Students Publications

No abstract provided.

Mitochondrial Ca2+ Uniporter (Mcu) Variants Form Plasma-Membrane Channels, Iuliia Polina, Jyotsna Mishra, Michael Cypress, Maria Landherr, Nedyalka Valkov, Isabel Chaput, Bridget Nieto, Brian Rhee, Ameneh Ahrari, Nathan Demichaelis, Kye-Im Jeon, Ulrike Mende, Peng Zhang, Bong Sook Jhun, Jin O-Uchi

Center for Translational Medicine Faculty Papers

MCU, originally known as CCDC109A, is widely recognized as the gene responsible for encoding a pore-forming subunit of a Ca2+-selective channel, mitochondrial Ca2+ uniporter complex (mtCUC). While MCU expression is typically highly mitochondrial-specific, we report here a protein variant derived from the MCU gene, termed MCU-S, which lacks the mitochondria-targeting sequence (MTS) and forms a Ca2+-permeable channel outside of mitochondria. The mRNA of MCU-S was ubiquitously expressed in all cell types/tissues tested, with particularly high expression in human platelets. MCU-S protein formed Ca2+ channels at the plasma membrane, which exhibited similar channel properties to those observed in mtCUC. MCU-S channels …

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, …

Barking Up The Right Tree: A Proposal For Uniform Canine Evidence Standards, Karly Koenig

St. Mary's Law Journal

No abstract provided.