Biochemistry, Biophysics, and Structural Biology Commons^™

Altered Myocardial Lipid Regulation In Junctophilin-2-Associated Familial Cardiomyopathies, Satadru K Lahiri, Feng Jin, Yue Zhou, Ann P Quick, Carlos F Kramm, Meng C Wang, Xander Ht Wehrens

Faculty, Staff and Students Publications

Myocardial lipid metabolism is critical to normal heart function, whereas altered lipid regulation has been linked to cardiac diseases including cardiomyopathies. Genetic variants in the JPH2 gene can cause hypertrophic cardiomyopathy (HCM) and, in some cases, dilated cardiomyopathy (DCM). In this study, we tested the hypothesis that JPH2 variants identified in patients with HCM and DCM, respectively, cause distinct alterations in myocardial lipid profiles. Echocardiography revealed clinically significant cardiac dysfunction in both knock-in mouse models of cardiomyopathy. Unbiased myocardial lipidomic analysis demonstrated significantly reduced levels of total unsaturated fatty acids, ceramides, and various phospholipids in both mice with HCM and …

Impact Of Obesity And Age On Mouse Corneal Innervation At The Epithelial-Stromal Interface, Justin A Courson, Rolando E Rumbaut, Alan R Burns

Faculty, Staff and Students Publications

PURPOSE: The corneal epithelium is the most highly innervated structure in the body. Previously, we reported a novel event whereby stromal axons fuse with basal epithelial cells, limiting nerve penetration into the epithelium. Although corneal-epithelial nerves undergo changes in sensitivity and distribution throughout life and in response to an obesogenic diet, it is unknown if neuronal-epithelial cell fusion is altered. Here, we sought to determine if neuronal-epithelial cell fusion frequency correlates with obesogenic diet consumption and age.

METHODS: Corneas were collected from C57BL/6 mice and evaluated for neuronal-epithelial cell fusion frequency using serial block-face scanning electron microscopy. To assess the …

Influence Of Rna Circularity On Target Rna-Directed Microrna Degradation, Federico Fuchs Wightman, Jerónimo Lukin, Sebastián A Giusti, Michael Soutschek, Laureano Bragado, Berta Pozzi, María L Pierelli, Paula González, Juan P Fededa, Gerhard Schratt, Rina Fujiwara, Jeremy E Wilusz, Damián Refojo, Manuel De La Mata

Faculty, Staff and Students Publications

A subset of circular RNAs (circRNAs) and linear RNAs have been proposed to 'sponge' or block microRNA activity. Additionally, certain RNAs induce microRNA destruction through the process of Target RNA-Directed MicroRNA Degradation (TDMD), but whether both linear and circular transcripts are equivalent in driving TDMD is unknown. Here, we studied whether circular/linear topology of endogenous and artificial RNA targets affects TDMD. Consistent with previous knowledge that Cdr1as (ciRS-7) circular RNA protects miR-7 from Cyrano-mediated TDMD, we demonstrate that depletion of Cdr1as reduces miR-7 abundance. In contrast, overexpression of an artificial linear version of Cdr1as drives miR-7 degradation. Using plasmids that …

Akap12 Upregulation Associates With Pde8a To Accelerate Cardiac Dysfunction, Hanan Qasim, Mehrdad Rajaei, Ying Xu, Arfaxad Reyes-Alcaraz, Hala Y Abdelnasser, M David Stewart, Satadru K Lahiri, Xander H T Wehrens, Bradley K Mcconnell

Faculty, Staff and Students Publications

BACKGROUND: In heart failure, signaling downstream the β2-adrenergic receptor is critical. Sympathetic stimulation of β2-adrenergic receptor alters cAMP (cyclic adenosine 3',5'-monophosphate) and triggers PKA (protein kinase A)-dependent phosphorylation of proteins that regulate cardiac function. cAMP levels are regulated in part by PDEs (phosphodiesterases). Several AKAPs (A kinase anchoring proteins) regulate cardiac function and are proposed as targets for precise pharmacology. AKAP12 is expressed in the heart and has been reported to directly bind β2-adrenergic receptor, PKA, and PDE4D. However, its roles in cardiac function are unclear.

METHODS: cAMP accumulation in real time downstream of the β2-adrenergic receptor was detected for …

Biomarkers For Managing Neurodegenerative Diseases, Lara Cheslow, Adam E. Snook, Scott A. Waldman

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Neurological disorders are the leading cause of cognitive and physical disability worldwide, affecting 15% of the global population. Due to the demographics of aging, the prevalence of neurological disorders, including neurodegenerative diseases, will double over the next two decades. Unfortunately, while available therapies provide symptomatic relief for cognitive and motor impairment, there is an urgent unmet need to develop disease-modifying therapies that slow the rate of pathological progression. In that context, biomarkers could identify at-risk and prodromal patients, monitor disease progression, track responses to therapy, and parse the causality of molecular events to identify novel targets for further clinical investigation. …

Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Prior studies showed that polyglutamine-expanded androgen receptor (AR) is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of nicotinamide adenine dinucleotide-dependent (NAD+-dependent) sirtuin 1 is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating postsymptomatic transgenic SBMA mice with the NAD+ precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of …

Centriole And Transition Zone Structures In Photoreceptor Cilia Revealed By Cryo-Electron Tomography, Zhixian Zhang, Abigail R Moye, Feng He, Muyuan Chen, Melina A Agosto, Theodore G Wensel

Faculty, Staff and Students Publications

Primary cilia mediate sensory signaling in multiple organisms and cell types but have structures adapted for specific roles. Structural defects in them lead to devastating diseases known as ciliopathies in humans. Key to their functions are structures at their base: the basal body, the transition zone, the "Y-shaped links," and the "ciliary necklace." We have used cryo-electron tomography with subtomogram averaging and conventional transmission electron microscopy to elucidate the structures associated with the basal region of the "connecting cilia" of rod outer segments in mouse retina. The longitudinal variations in microtubule (MT) structures and the lumenal scaffold complexes connecting them …

In Vivo Dynamic Volumetric Imaging Of Mouse Testis And Epididymis With Optical Coherence Tomography†, Kohei Umezu, Guzel R Musina, Irina V Larina

Faculty, Staff and Students Publications

The implementation of live imaging in reproductive research is crucial for studying the physiological dynamics. Sperm transport is a highly dynamic process regulated by tubular contractions and luminal flows within the male reproductive tract. However, due to the lack of imaging techniques to capture these dynamics in vivo, there is little information on the physiological and biomechanical regulation of sperm transport through the male reproductive tract. Here, we present a functional in vivo imaging approach using optical coherence tomography, enabling live, label-free, depth-resolved, three-dimensional, high-resolution visualization of the mouse testis and epididymis. With this approach, we spatiotemporally captured tubular contractility …

Endothelial Cells Adopt A Pro-Reparative Immune Responsive Signature During Cardiac Injury, Hali Long, Jeffrey D Steimle, Francisco Jose Grisanti Canozo, Jong Hwan Kim, Xiao Li, Yuka Morikawa, Minjun Park, Diwakar Turaga, Iki Adachi, Joshua D Wythe, Md Abul Hassan Samee, James F Martin

Faculty, Staff and Students Publications

Modulation of the heart’s immune microenvironment is crucial for recovery after ischemic events such as myocardial infarction (MI). Endothelial cells (ECs) can have immune regulatory functions; however, interactions between ECs and the immune environment in the heart after MI remain poorly understood. We identified an EC-specific IFN responsive and immune regulatory gene signature in adult and pediatric heart failure (HF) tissues. Single-cell transcriptomic analysis of murine hearts subjected to MI uncovered an EC population (IFN-ECs) with immunologic gene signatures similar to those in human HF. IFN-ECs were enriched in regenerative-stage mouse hearts and expressed genes encoding immune responsive transcription factors …

Comparative Animal Mucomics, Antonio R. Cerullo

Dissertations, Theses, and Capstone Projects

Mucus is one of Nature’s most abundant and versatile biomaterials. These secretions are present in all animals, from the lowly garden snail to the great blue whale, and fulfill a multitude of functions, acting as antimicrobial barriers, moisturizers, adhesive glues, surface lubricants, and mineralizing agents. Despite their importance, very little is known about mucus compositions or properties. The largest challenge precluding the greater understanding of mucus function is its complexity; a single mucus contains complex mixtures of proteins, glycans, and ions that all have important roles in function. Therefore, understanding mucus function necessitates analysis that compares different mucus from one …

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−, …

Fused In Sarcoma Regulates Glutamate Signaling And Oxidative Stress Response, Chiong-Hee Wong, Abu Rahat, Howard C Chang

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Mutations in fused in sarcoma (fust-1) are linked to ALS. However, how these ALS causative mutations alter physiological processes and lead to the onset of ALS remains largely unknown. By obtaining humanized fust-1 ALS mutations via CRISPR-CAS9, we generated a C. elegans ALS model. Homozygous fust-1 ALS mutant and fust-1 deletion animals are viable in C. elegans. This allows us to better characterize the molecular mechanisms of fust-1-dependent responses. We found FUST-1 plays a role in regulating superoxide dismutase, glutamate signaling, and oxidative stress. FUST-1 suppresses SOD-1 and VGLUT/EAT-4 in the nervous system. FUST-1 also regulates synaptic AMPA-type glutamate receptor …

Β2-Glycoprotein I Promotes The Clearance Of Circulating Mitochondria, Swapan Kumar Dasgupta, Jahnavi Gollamudi, Stefanie Rivera, Ross A Poche, Rolando E Rumbaut, Perumal Thiagarajan

Faculty, Staff and Students Publications

β2-glycoprotein I (β2-Gp1) is a cardiolipin-binding plasma glycoprotein. It is evolutionarily conserved from invertebrates, and cardiolipin-bound β2-Gp1 is a major target of antiphospholipid antibodies seen in autoimmune disorders. Cardiolipin is almost exclusively present in mitochondria, and mitochondria are present in circulating blood. We show that β2-Gp1 binds to cell-free mitochondria (CFM) in the circulation and promotes its phagocytosis by macrophages at physiological plasma concentrations. Exogenous CFM had a short circulation time of less than 10 minutes in mice. Following infusion of CFM, β2-Gp1-deficient mice had significantly higher levels of transfused mitochondria at 5 minutes (9.9 ± 6.4 pg/ml versus 4.0 …

Inhibition Of Src-3 As A Potential Therapeutic Strategy For Aggressive Mantle Cell Lymphoma, Imani Bijou, Yang Liu, Dong Lu, Jianwei Chen, Shelby Sloan, Lapo Alinari, David M Lonard, Bert W O'Malley, Michael Wang, Jin Wang

Faculty, Staff and Students Publications

Mantle cell lymphoma (MCL) has a poor prognosis and high relapse rates despite current therapies, necessitating novel treatment regimens. Inhibition of SRC-3 show effectiveness in vivo and in vitro in other B cell lymphomas. Additionally, previous studies have shown that SRC-3 is highly expressed in the lymph nodes of B cell non-Hodgkin's lymphoma patients, suggesting SRC-3 may play a role in the progression of B cell lymphoma. This study aimed to investigate novel SRC-3 inhibitors, SI-10 and SI-12, in mantle cell lymphoma. The cytotoxic effects of SI-10 and SI-12 were evaluated in vitro and demonstrated dose-dependent cytotoxicity in a panel …

Targeting Eif4a Triggers An Interferon Response To Synergize With Chemotherapy And Suppress Triple-Negative Breast Cancer, Na Zhao, Elena B Kabotyanski, Alexander B Saltzman, Anna Malovannaya, Xueying Yuan, Lucas C Reineke, Nadia Lieu, Yang Gao, Diego A Pedroza, Sebastian J Calderon, Alex J Smith, Clark Hamor, Kazem Safari, Sara Savage, Bing Zhang, Jianling Zhou, Luisa M Solis, Susan G Hilsenbeck, Cheng Fan, Charles M Perou, Jeffrey M Rosen

Faculty, Staff and Students Publications

Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A with zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages toward an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 …

An Automated Respiratory Data Pipeline For Waveform Characteristic Analysis, Savannah Lusk, Christopher S Ward, Andersen Chang, Avery Twitchell-Heyne, Shaun Fattig, Genevera Allen, Joanna L Jankowsky, Russell S Ray

Faculty, Staff and Students Publications

Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by …

Increasing Glutathione Levels By A Novel Posttranslational Mechanism Inhibits Neuronal Hyperexcitability, Ashwini Sri Hari, Rajeswari Banerji, Li-Ping Liang, Ruth E Fulton, Christopher Quoc Huynh, Timothy Fabisiak, Pallavi Bhuyan Mcelroy, James R Roede, Manisha Patel

Faculty, Staff and Students Publications

Glutathione (GSH) depletion, and impaired redox homeostasis have been observed in experimental animal models and patients with epilepsy. Pleiotropic strategies that elevate GSH levels via transcriptional regulation have been shown to significantly decrease oxidative stress and seizure frequency, increase seizure threshold, and rescue certain cognitive deficits. Whether elevation of GSH per se alters neuronal hyperexcitability remains unanswered. We previously showed that thiols such as dimercaprol (DMP) elevate GSH via post-translational activation of glutamate cysteine ligase (GCL), the rate limiting GSH biosynthetic enzyme. Here, we asked if elevation of cellular GSH by DMP altered neuronal hyperexcitability in-vitro and in-vivo. Treatment of …

A Small-Molecule Inhibitor Of Topbp1 Exerts Anti-Myc Activity And Synergy With Parp Inhibitors, Fang-Tsyr Lin, Kang Liu, Lidija A Wilhelms Garan, Helena Folly-Kossi, Yongcheng Song, Shwu-Jiuan Lin, Weei-Chin Lin

Faculty, Staff and Students Publications

We have previously identified TopBP1 (topoisomerase IIβ-binding protein 1) as a promising target for cancer therapy, given its role in the convergence of Rb, PI(3)K/Akt, and p53 pathways. Based on this, we conducted a large-scale molecular docking screening to identify a small-molecule inhibitor that specifically targets the BRCT7/8 domains of TopBP1, which we have named 5D4. Our studies show that 5D4 inhibits TopBP1 interactions with E2F1, mutant p53, and Cancerous Inhibitor of Protein Phosphatase 2A. This leads to the activation of E2F1-mediated apoptosis and the inhibition of mutant p53 gain of function. In addition, 5D4 disrupts the interaction of TopBP1 …

Widefield Imaging Of Rapid Pan-Cortical Voltage Dynamics With An Indicator Evolved For One-Photon Microscopy, Xiaoyu Lu, Yunmiao Wang, Zhuohe Liu, Yueyang Gou, Dieter Jaeger, François St-Pierre

Faculty, Staff and Students Publications

Widefield imaging with genetically encoded voltage indicators (GEVIs) is a promising approach for understanding the role of large cortical networks in the neural coding of behavior. However, the limited performance of current GEVIs restricts their deployment for single-trial imaging of rapid neuronal voltage dynamics. Here, we developed a high-throughput platform to screen for GEVIs that combine fast kinetics with high brightness, sensitivity, and photostability under widefield one-photon illumination. Rounds of directed evolution produced JEDI-1P, a green-emitting fluorescent indicator with enhanced performance across all metrics. Next, we optimized a neonatal intracerebroventricular delivery method to achieve cost-effective and wide-spread JEDI-1P expression in …

Opposing Roles For The Α Isoform Of The Catalytic Subunit Of Protein Phosphatase 1 In Inside-Out And Outside-In Integrin Signaling In Murine Platelets, Tanvir Khatlani, Subhashree Pradhan, Kimberly Langlois, Deepika Subramanyam, Rolando E Rumbaut, K Vinod Vijayan

Faculty, Staff and Students Publications

Platelet activation during hemostasis and thrombosis is facilitated by agonist-induced inside–out and integrin αIIbβ3-initiated outside–in signaling via protein kinases and phosphatases. Pharmacological inhibitor studies suggest that the serine/threonine protein phosphatase 1 (PP1) promotes platelet activation. However, since phosphatase inhibitors block all the isoforms of the catalytic subunit of PP1 (PP1c), the role of specific PP1c isoform in platelet signaling remains unclear. Here, we employed a platelet-specific PP1cα−/− mice to explore the contribution of a major PP1 isoform in platelet functions. Loss of PP1cα moderately decreased activation of integrin αIIbβ3, binding of soluble fibrinogen, and aggregation to low-dose thrombin, ADP, and …

Novel Treatments For Pxe: Targeting The Systemic And Local Drivers Of Ectopic Calcification, Ida Joely Jacobs, Qiaoli Li

Department of Biochemistry and Molecular Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable multisystem ectopic calcification disorder. The gene responsible for PXE, ABCC6, encodes ABCC6, a hepatic efflux transporter regulating extracellular inorganic pyrophosphate (PPi), a potent endogenous calcification inhibitor. Recent studies demonstrated that in addition to the deficiency of plasma PPi, the activated DDR/PARP signaling in calcified tissues provides an additional possible mechanism of ectopic calcification in PXE. This study examined the effects of etidronate (ETD), a stable PPi analog, and its combination with minocycline (Mino), a potent inhibitor of DDR/PARP, on ectopic calcification in an Abcc6-/- mouse model of PXE. Abcc6-/- mice, at 4 weeks of …

Spa-Stocsy: An Automated Tool For Identifying Annotated And Non-Annotated Metabolites In High-Throughput Nmr Spectra, Xu Han, Wanli Wang, Li-Hua Ma, Ismael Ai-Ramahi, Juan Botas, Kevin Mackenzie, Genevera I Allen, Damian W Young, Zhandong Liu, Mirjana Maletic-Savatic

Faculty, Staff and Students Publications

MOTIVATION: Nuclear magnetic resonance spectroscopy (NMR) is widely used to analyze metabolites in biological samples, but the analysis requires specific expertise, it is time-consuming, and can be inaccurate. Here, we present a powerful automate tool, SPatial clustering Algorithm-Statistical TOtal Correlation SpectroscopY (SPA-STOCSY), which overcomes challenges faced when analyzing NMR data and identifies metabolites in a sample with high accuracy.

RESULTS: As a data-driven method, SPA-STOCSY estimates all parameters from the input dataset. It first investigates the covariance pattern among datapoints and then calculates the optimal threshold with which to cluster datapoints belonging to the same structural unit, i.e. the metabolite. …

Chronic Kidney Disease Promotes Atrial Fibrillation Via Inflammasome Pathway Activation, Jia Song, Jose Alberto Navarro-Garcia, Jiao Wu, Arnela Saljic, Issam Abu-Taha, Luge Li, Satadru K Lahiri, Joshua A Keefe, Yuriana Aguilar-Sanchez, Oliver M Moore, Yue Yuan, Xiaolei Wang, Markus Kamler, William E Mitch, Gema Ruiz-Hurtado, Zhaoyong Hu, Sandhya S Thomas, Dobromir Dobrev, Xander Ht Wehrens, Na Li

Faculty, Staff and Students Publications

Chronic kidney disease (CKD) is associated with a higher risk of atrial fibrillation (AF). The mechanistic link between CKD and AF remains elusive. IL-1β, a main effector of NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation, is a key modulator of conditions associated with inflammation, such as AF and CKD. Circulating IL-1β levels were elevated in patients with CKD who had AF (versus patients with CKD in sinus rhythm). Moreover, NLRP3 activity was enhanced in atria of patients with CKD. To elucidate the role of NLRP3/IL-1β signaling in the pathogenesis of CKD-induced AF, Nlrp3-/- and WT mice were subjected to …

Kinome Reprogramming Is A Targetable Vulnerability In Esr1 Fusion-Driven Breast Cancer, Xuxu Gou, Beom-Jun Kim, Meenakshi Anurag, Jonathan T Lei, Meggie N Young, Matthew V Holt, Diana Fandino, Craig T Vollert, Purba Singh, Mohammad A Alzubi, Anna Malovannaya, Lacey E Dobrolecki, Michael T Lewis, Shunqiang Li, Charles E Foulds, Matthew J Ellis

Faculty, Staff and Students Publications

Transcriptionally active ESR1 fusions (ESR1-TAF) are a potent cause of breast cancer endocrine therapy (ET) resistance. ESR1-TAFs are not directly druggable because the C-terminal estrogen/anti-estrogen-binding domain is replaced with translocated in-frame partner gene sequences that confer constitutive transactivation. To discover alternative treatments, a mass spectrometry (MS)-based kinase inhibitor pulldown assay (KIPA) was deployed to identify druggable kinases that are upregulated by diverse ESR1-TAFs. Subsequent explorations of drug sensitivity validated RET kinase as a common therapeutic vulnerability despite remarkable ESR1-TAF C-terminal sequence and structural diversity. Organoids and xenografts from a pan-ET-resistant patient-derived xenograft model that harbors the ESR1-e6>YAP1 TAF were …

The Transcription Factor Chrebp Links Mitochondrial Lipidomes To Mitochondrial Morphology And Progression Of Diabetic Kidney Disease, Li Li, Jianyin Long, Koki Mise, Naravat Poungavrin, Philip L Lorenzi, Iqbal Mahmud, Lin Tan, Pradip K Saha, Yashpal S Kanwar, Benny H Chang, Farhad R Danesh

Faculty, Staff and Students Publications

A substantial body of evidence has established the contributions of both mitochondrial dynamics and lipid metabolism to the pathogenesis of diabetic kidney disease (DKD). However, the precise interplay between these two key metabolic regulators of DKD is not fully understood. Here, we uncover a link between mitochondrial dynamics and lipid metabolism by investigating the role of carbohydrate-response element-binding protein (ChREBP), a glucose-responsive transcription factor and a master regulator of lipogenesis, in kidney podocytes. We find that inducible podocyte-specific knockdown of ChREBP in diabetic db/db mice improves key biochemical and histological features of DKD in addition to significantly reducing mitochondrial fragmentation. …

Oleoylethanolamide Facilitates Pparα And Tfeb Signaling And Attenuates Aβ Pathology In A Mouse Model Of Alzheimer’S Disease, Michele M Comerota, Manasee Gedam, Wen Xiong, Feng Jin, Lisheng Deng, Meng C Wang, Jin Wang, Hui Zheng

Faculty, Staff and Students Publications

BACKGROUND: Age is the strongest risk factor for the development of Alzheimer's disease (AD). Besides the pathological hallmarks of β-amyloid (Aβ) plaques and neurofibrillary tangles, emerging evidence demonstrates a critical role of microglia and neuroinflammation in AD pathogenesis. Oleoylethanolamide (OEA) is an endogenous lipid amide that has been shown to promote lifespan and healthspan in C. elegans through regulation of lysosome-to-nucleus signaling and cellular metabolism. The goal of our study was to determine the role of OEA in the mediation of microglial activity and AD pathology using its stable analog, KDS-5104.

METHODS: We used primary microglial cultures and genetic and …

Spatial Organization Of The Mouse Retina At Single Cell Resolution By Merfish, Jongsu Choi, Jin Li, Salma Ferdous, Qingnan Liang, Jeffrey R Moffitt, Rui Chen

Faculty, Staff and Students Publications

The visual signal processing in the retina requires the precise organization of diverse neuronal types working in concert. While single-cell omics studies have identified more than 120 different neuronal subtypes in the mouse retina, little is known about their spatial organization. Here, we generated the single-cell spatial atlas of the mouse retina using multiplexed error-robust fluorescence in situ hybridization (MERFISH). We profiled over 390,000 cells and identified all major cell types and nearly all subtypes through the integration with reference single-cell RNA sequencing (scRNA-seq) data. Our spatial atlas allowed simultaneous examination of nearly all cell subtypes in the retina, revealing …

Study Of Polytopic Membrane Protein Topological Organization As A Function Of Membrane Lipid Composition, Takefumi Morizumi, Kyumhyuk Kim, Hai Li, Elena G Govorunova, Oleg A Sineshchekov, Yumei Wang, Lei Zheng, Éva Bertalan, Ana-Nicoleta Bondar, Azam Askari, Leonid S Brown, John L Spudich, Oliver P Ernst

Faculty, Staff and Student Publications

Kalium channelrhodopsin 1 from Hyphochytrium catenoides (HcKCR1) is a light-gated channel used for optogenetic silencing of mammalian neurons. It selects K+ over Na+ in the absence of the canonical tetrameric K+ selectivity filter found universally in voltage- and ligand-gated channels. The genome of H. catenoides also encodes a highly homologous cation channelrhodopsin (HcCCR), a Na+ channel with >100-fold larger Na+ to K+ permeability ratio. Here, we use cryo-electron microscopy to determine atomic structures of these two channels embedded in peptidiscs to elucidate structural foundations of their dramatically different cation selectivity. Together with structure-guided mutagenesis, we show that K+ versus Na+ …

Molecular Dissection And Testing Of Prss37 Function Through Lc-Ms/Ms And The Generation Of A Prss37 Humanized Mouse Model, Courtney Sutton, Kaori Nozawa, Katarzyna Kent, Alexander Saltzman, Mei Leng, Sureshbabu Nagarajan, Anna Malovannaya, Masahito Ikawa, Thomas X Garcia, Martin M Matzuk

Faculty, Staff and Students Publications

The quest for a non-hormonal male contraceptive pill for men still exists. Serine protease 37 (PRSS37) is a sperm-specific protein that when ablated in mice renders them sterile. In this study we sought to examine the molecular sequelae of PRSS37 loss to better understand its molecular function, and to determine whether human PRSS37 could rescue the sterility phenotype of knockout (KO) mice, allowing for a more appropriate model for drug molecule testing. To this end, we used CRISPR-EZ to create mice lacking the entire coding region of Prss37, used pronuclear injection to create transgenic mice expressing human PRSS37, intercrossed these …

Tiam1 Coordinates Synaptic Structural And Functional Plasticity Underpinning The Pathophysiology Of Neuropathic Pain, Lingyong Li, Qin Ru, Yungang Lu, Xing Fang, Guanxing Chen, Ali Bin Saifullah, Changqun Yao, Kimberley F Tolias

Faculty, Staff and Students Publications

Neuropathic pain is a common, debilitating chronic pain condition caused by damage or a disease affecting the somatosensory nervous system. Understanding the pathophysiological mechanisms underlying neuropathic pain is critical for developing new therapeutic strategies to treat chronic pain effectively. Tiam1 is a Rac1 guanine nucleotide exchange factor (GEF) that promotes dendritic and synaptic growth during hippocampal development by inducing actin cytoskeletal remodeling. Here, using multiple neuropathic pain animal models, we show that Tiam1 coordinates synaptic structural and functional plasticity in the spinal dorsal horn via actin cytoskeleton reorganization and synaptic NMDAR stabilization and that these actions are essential for the …