Neurosciences Commons^™

Selective Loss Of Primary Cilia And Neurotrophic Signaling In G51d Α-Synuclein Mice Highlights A Common Pathway To Parkinson’S Disease, Yu-En Lin, Ebsy Jaimon, Youngdoo Kim, Annabeth Loftman, Aaran Vijayakumaran, Benjamin D W Belfort, Claire Y Chiang, Benjamin R Arenkiel, Huda Y Zoghbi, Suzanne R Pfeffer

Duncan NRI Faculty and Staff Publications

Parkinson's disease is characterized by dopaminergic neuron loss and accumulation of α-synuclein aggregates in the brain. G51D α-synuclein knock-in mice provide a genetically and clinically relevant model of disease, exhibiting early olfactory deficits, age-dependent motor impairment, and progressive phospho-α-synuclein accumulation. In multiple Parkinson's disease models, striatal cholinergic and parvalbumin interneurons, as well as astrocytes, lose primary cilia and the neurotrophic signaling needed to sustain dopaminergic neurons. We show here that G51D α-synuclein mice share these phenotypes. Phospho-Ser129 α-synuclein accumulation correlates with cilia loss in cholinergic interneurons but not in spiny projection neurons that accumulate higher phospho-α-synuclein levels. In the piriform …

Translational Reading Frame Predicts The Pathogenicity Of C-Terminal Frameshift Deletions In Mecp2, Jacky Guy, Elena Hein, Beatrice Alexander-Howden, Timur Von Bock Und Polach, Tricia Mathieson, Benjamin P Kleinstiver, Huda Y Zoghbi, Adrian Bird

Duncan NRI Faculty and Staff Publications

Mutations in the MECP2 gene cause the severe neurological disorder Rett syndrome. A cluster of frameshift-causing C-terminal deletions (CTDs) removes ~100 amino acids and accounts for approximately 10% of RTT-causing mutations. Their pathogenicity is unexpected because this C-terminal domain is dispensable in mice. Analysis of pathogenic and benign human MECP2 variants reveals that some individuals with apparently typical CTDs do not develop Rett syndrome, confirming that C-terminal truncations are not intrinsically pathogenic. Using human sequence data and mouse models we show that pathogenicity results from a marked reduction in MeCP2 levels and depends on the presence of a proline proline …

Statistics Of Natural Scenes Shape Contextual Modulation In The Visual Cortex, Jiakun Fu, Suhas Shrinivasan, Luca Baroni, Zhuokun Ding, Paul G Fahey, Paweł A Pierzchlewicz, Nikos Karantzas, Kayla Ponder, Rachel Froebe, Lydia Ntanavara, Taliah Muhammad, Konstantin F Willeke, Eric Wang, Zhiwei Ding, Dat Tran, Stelios Papadopoulos, Saumil Patel, Jacob Reimer, Alexander S Ecker, Xaq Pitkow, Jan Antolik, Fabian H Sinz, Ralf M Haefner, Andreas S Tolias, Katrin Franke

Faculty, Staff and Students Publications

Vision is context dependent, with neuronal responses shaped not only by local features but also by surrounding visual input. While classical studies, using grating stimuli, show that iso-oriented surrounds suppress responses more than orthogonal surrounds, the role of contextual modulation under natural stimulus conditions remains less clear. Using recordings from mouse primary visual cortex (V1), we trained convolutional neural network models to predict neuronal responses to natural images and synthesized surround stimuli that selectively suppressed or facilitated responses to optimal center inputs. In vivo experiments confirmed these predictions. Facilitatory surrounds resembled naturalistic continuations of the optimal center stimulus, consistent with …

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 …

Activated Dorsomedial Hypothalamic Astrocytes Regulate Feeding Behavior, Bella M. Lisenby

Honors Projects

The dorsomedial hypothalamus (DMH) region of the brain has been shown to be important for anticipatory feeding activity and play a role in restricting excessive food intake. In obese animals that overconsume calories, astrocytes within the DMH exhibit intracellular signaling changes indicative of cellular activation. Because astrocytes are known to influence neuronal function, we hypothesize that activated astrocytes regulate behavior. In the current study, we use chemogenetics combined with stereotaxic surgery to assess the contribution of astrocyte activity in the DMH towards metabolic behaviors.

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, …

Platelets Cause Microvascular Occlusion And Delayed Neurological Deficits After Subarachnoid Hemorrhage In Mice., Ari Dienel, Sung-Ha Hong, Kiara Torres, Kanako Matsumura, Jose Guzman, Peeyush Thankamani Pandit, Bibek Samal, Harveen Kaur, Samitha Nemirajaiah, Angelica Bernal, H Alex Choi, Louise D Mccullough, Spiros L Blackburn, Jaroslaw Aronowski, Devin W Mcbride

Faculty, Staff and Student Publications

After subarachnoid hemorrhage (SAH), some patients develop delayed neurological deficits (DND). Microthrombi are considered a contributing factor to DND, but clinical trials of antiplatelets had mixed results. Existing research suggests that platelets play a role in the etiology of DND, but no comprehensive study has tested causality between platelets and DND after SAH. Here we hypothesize that after SAH, platelet activation promotes microthrombi formation, occlusion of the brain microvasculature and contributes to DND, and that inhibiting platelet aggregation is a therapeutic strategy. Mice experiencing SAH were administered various interventions. The animals were subjected to stimulation of platelets, platelet depletion, or …

Efficient In Vivo Pharmacological Inhibition Of Δfosb, An Ap-1 Transcription Factor, In The Brain, Sean Mcneme, Anil Kumar, Yun Young Yim, Brandon W Hughes, Corey St Romain, Yi Li, Ashwani Kumar, Qichao Bao, Molly Estill, Shanghua Fan, Nadeen Takatka, Earnest P Chen, Matthew Rivera, Haiying Chen, Alfred J Robison, Mischa Machius, Stephen J Haggarty, Jeannie Chin, Eric J Nestler, Jia Zhou, Gabby Rudenko

Faculty, Staff and Students Publications

ΔFOSB, an unusually stable member of the AP-1 family of transcription factors, mediates long-term maladaptations that play a key role in the pathogenesis of drug addiction, cognitive decline, dyskinesia, and several other chronic neurological and psychiatric conditions. We have recently identified that 2-phenoxybenzenesulfonic acid-containing compounds disrupt the binding of ΔFOSB to DNA in vitro in cell-based assays, and one such compound, JPC0661, disrupts ΔFOSB binding to genomic DNA in vivo in the mouse brain with partial efficiency. JPC0661 binds to a groove outside of the DNA-binding cleft of the ΔFOSB/JUND bZIP heterodimer in a cocrystal structure. Here, we generated a …

Functional Bipartite Invariance In Mouse Primary Visual Cortex Receptive Fields, Zhiwei Ding, Dat Tran, Kayla Ponder, Zhuokun Ding, Rachel Froebe, Lydia Ntanavara, Paul G Fahey, Erick Cobos, Luca Baroni, Maria Diamantaki, Eric Y Wang, Andersen Chang, Stelios Papadopoulos, Jiakun Fu, Taliah Muhammad, Christos Papadopoulos, Santiago A Cadena, Alexandros Evangelou, Konstantin Willeke, Fabio Anselmi, Sophia Sanborn, Jan Antolik, Emmanouil Froudarakis, Saumil Patel, Edgar Y Walker, Jacob Reimer, Fabian H Sinz, Alexander S Ecker, Katrin Franke, Xaq Pitkow, Andreas S Tolias

Faculty, Staff and Students Publications

Sensory systems support generalization by representing features that persist under input variation; however, identifying the neuronal basis of these invariances remains difficult due to high-dimensional and nonlinear neural computations. Here we leverage the inception loop paradigm, iterating between large-scale recordings, predictive models and in silico experiments with in vivo verification, to characterize neuronal invariances in mouse primary visual cortex (V1). We synthesize varied exciting inputs (VEIs), dissimilar images that drive target neurons. These VEIs revealed a new bipartite invariance: one subfield encodes a shift-tolerant high-frequency texture and the other encodes a fixed low-frequency pattern. This division aligns with object boundaries …

High-Power Dual-Channel Chamber For High-Frequency Magnetic Neuromodulation, Xiaoyang Tian, Hui Wang, Boshuo Wang, Jinshui Zhang, Dong Yan, Jeannette Ingabire, Samantha Coffler, Guillaume Duret, Quoc-Khanh Pham, Gang Bao, Junzhe Wang, Ashok Veeraraghavan, Jacob T Robinson, Stefan M Goetz, Angel V Peterchev

Faculty, Staff and Students Publications

Objective. Several novel methods, including magnetogenetics and magnetoelectric stimulation, use high frequency alternating magnetic fields to precisely manipulate neural activity. To quantify the behavioral effects of such interventions in a freely moving mouse, we developed a dual-channel magnetic chamber, specifically designed for rate-sensitive magnetothermal-genetic stimulation, and adaptable for other uses of alternating magnetic fields.

Approach. Through an optimized coil design, the system allows independent control of two spatially orthogonal uniform magnetic fields delivered at different frequencies within a 10 × 10 × 6 cm3 chamber suitable for mouse studies. The two channels have nominal frequencies of 50 and 550 kHz …

Non-Synaptic Function And Localization Of Syntaxin-Binding Protein 1 In A Mouse Model Of Stxbp1-Related Epileptic Encephalopathy, Tao Yang, Rajat Banerjee, Yamei Deng, Sheetal Jahagirdar, Joo Hyun Kim, Wu Chen, Mingshan Xue, Alexey I Nesvizhskii, Michael D Uhler, Jack M Parent, Yu Wang

Duncan NRI Faculty and Staff Publications

Objective: De novo mutations in the syntaxin-binding protein 1 (STXBP1), encoded by STXBP1, are among the most prevalent causes of variable neurodevelopmental disorders, including epileptic encephalopathy, developmental delay, and movement disorders. Although STXBP1 has been proposed as a critical presynaptic protein controlling synaptic vesicle exocytosis, clinical phenotypes also suggest that its biological function could be more diverse.

Methods: The expression pattern of STXBP1 was studied using immunostaining in vitro and in vivo. Synaptosome isolation was performed to investigate the synaptic and non-synaptic localization of STXBP1 in the brain. STXBP1 immunoprecipitation followed by mass spectrometry (MS) was conducted to identify protein …

Tead-Independent Mechanisms Of Yap Function In Cardiomyocyte Cell Cycle Reentry, Bing Xie, Jeffrey Steimle, Vaibhav Deshmukh, Lin Liu, Chang-Ru Tsai, Todd R Heallen, Wyatt Paltzer, Yuka Morikawa, Fansen Meng, Jun Wang, James F Martin

Faculty, Staff and Students Publications

Adult mammalian hearts exhibit limited regenerative capacity because of the restricted renewal of cardiomyocytes. Recent studies reveal that mammalian hearts exhibit transient regenerative potential within a short time frame after birth, suggesting a regulatory mechanism that prevents adult hearts from initiating a regenerative response to cardiac injury. Here, we discovered that an active form of YAP, named YAP6SA, which is not inhibited by the Hippo signaling pathway and does not interact with TEADs, induces cardiomyocyte cell cycle reentry. In addition, YAP6SA interacts with scaffold protein MPDZ to regulate Rho GTPases and promote cell cycle progression in cardiomyocytes (CMs). Importantly, YAP6SA …

Noradrenergic Innervation Across Brain Regions Is Altered By Aging And By Disease Progression In A Mouse Model Of Alzheimer’S Disease Neuropathology, Nicole M Hernandez, Manuel Silva-Pérez, Jeannie Chin

Faculty, Staff and Students Publications

Norepinephrine plays critical roles in modulating arousal and attention, is highly dynamic in awake, behaving individuals, and has anti-inflammatory and neuroprotective actions. Notably, the locus coeruleus (LC), the primary source of norepinephrine in the central nervous system, is among the first brain regions to show pathological alterations in early stages of Alzheimer's disease (AD). LC neuronal loss and associated reductions in norepinephrine in the brain have therefore been postulated to play a key role in AD pathophysiology. LC neurons and their axons have been studied in several mouse models of AD-related neuropathology to investigate their contribution to brain dysfunction in …

Metabolomic Profiling Reveals Brain Lipid Alterations In Pex7-Deficient Models Of Rhizomelic Chondrodysplasia Punctata, Riya Sankhe, Meredith I Williams, Wedad Fallatah, Laura Mackay, Mary Layne Brown, Pranjali Bhagwat, Sarah H Elsea, Nancy Braverman, Michael F Wangler

Duncan NRI Faculty and Staff Publications

Rhizomelic chondrodysplasia punctata type 1 (RCDP1) is a peroxisomal disorder characterized by skeletal shortening, intellectual disability, seizures, cataracts, and reduced lifespans. RCDP1 is caused by biallelic loss-of-function variants in PEX7, which encodes a protein required for importing select enzymes into the peroxisome matrix, including those essential for ether lipid synthesis (e.g., plasmalogens) and the branched-chain fatty acid catabolism. Plasmalogen deficiency is a hallmark of RCDP1 and other peroxisomal disorders, including RCDP types 2-5 (RCDP2-5) and Zellweger spectrum disorders (ZSD). Here, we performed comprehensive metabolomic profiling of clinical samples from RCDP patients and Pex7-deficient mouse models. We identified profound …

Protein-Protein Interaction–Interfering Peptide Rescues Dysregulated Nmda Receptor Signaling, Robert E. Featherstone, Hongbin Li, Ameet S. Sengar, Karin E. Borgmann-Winter, Olya Melnychenko, Lindsey M. Crown, Ray L. Gifford, Felix Amirfathi, Anamika Banerjee, Aivi Tran, Krishna Parekh, Margaret Heller, Wenyu Zhang, Robert J. Gallop, Adam D. Marc, Pragya Komal, Michael W. Salter, Steven J. Siegel, Chang-Gyu Hahn

Farber Institute for Neuroscience Faculty Papers

The complex and heterogeneous genetic architecture of neuropsychiatric illnesses compels us to look beyond individual risk genes for therapeutic strategies and target the interactive dynamics and convergence of their protein products. A mechanistic substrate for convergence of synaptic neuropsychiatric risk genes are protein-protein interactions (PPIs) in the N-methyl-D-aspartate receptor (NMDAR) complex. NMDAR hypofunction in schizophrenia is associated with hypoactivity of Src kinase, resulting from convergent alterations in PPIs of Src with its partners. Of these, the association of Src with PSD-95, which inhibits the activity of this kinase in the NMDAR complex, is known to be increased in schizophrenia. Here, …

Restoration Of Sfrp3 Preserves The Neural Stem Cell Pool And Spatial Discrimination Ability In A Mouse Model Of Alzheimer's Disease, Chia-Hsuan Fu, Jin Park, Umberto Tosi, Francisco A Blanco, Manuel Silva-Pérez, Kavitha Muralidharan, Jason C You, Minjung Lee, Gabriel S Stephens, Xiaohong Zhang, Yi Zheng, Helen Scharfman, Kimberley F Tolias, Jeannie Chin

Faculty, Staff and Students Publications

Individuals with Alzheimer's disease (AD) have an increased incidence of seizures, which worsen cognitive decline. Using a transgenic mouse model of AD neuropathology that exhibits spontaneous seizures, we previously found that seizure activity stimulates and accelerates depletion of the hippocampal neural stem cell (NSC) pool, which was associated with deficits in neurogenesis-dependent spatial discrimination. However, the precise molecular mechanisms that drive seizure-induced activation and depletion of NSCs are unclear. Here, using mice of both sexes, we performed RNA-sequencing on the hippocampal dentate gyrus and identified differentially expressed regulators of neurogenesis in the Wnt signaling pathway that regulates many aspects of …

A Distinct Pp2a Subunit Regulates Local Protein Phosphorylation At The Axon Initial Segment, Andrew P Anderson, Sanghyun Kim, Allison J Melton, Xiaoyun Ding, Wei Zhang, Alexander B Saltzman, Anna Malovannaya, Matthew N Rasband, Yudong Gao

Faculty, Staff and Students Publications

Protein phosphorylation plays a crucial role in regulating the cytoskeletal and membrane proteins at the axon initial segment (AIS). However, our knowledge of AIS-specific kinases and phosphatases is very limited. Here, we report the identification of a protein phosphatase 2A (PP2A) B55 regulatory subunit enriched at the AIS in mice: Ppp2r2c. Our results demonstrate that PP2A-B55 subunits exhibit substantial heterogeneity in their subcellular localization and function. Notably, the Ppp2r2c subunit is selectively concentrated at the AIS, and this enrichment is driven by its unique structure. Utilizing a microelectrode array system (MEA), we show that Ppp2r2c modulates neuronal activity during in …

Loss Of The Lysosomal Protein Cln3 Triggers C-Abl-Dependent Yap1 Pro-Apoptotic Signaling, Neuza Domingues, Alessia Calcagni', Sofia Freire, Joana Pires, Ricardo Casqueiro, Ivan L Salazar, Niculin Joachim Herz, Tuong Huynh, Katarzyna Wieciorek, Tiago Fleming Outeiro, Henrique Girão, Ira Milosevic, Andrea Ballabio, Nuno Raimundo

Duncan NRI Faculty and Staff Publications

Batten disease is characterized by early-onset blindness, juvenile dementia and death within the second decade of life. The most common genetic cause are mutations in CLN3, encoding a lysosomal protein. Currently, no therapies targeting disease progression are available, largely because its molecular mechanisms remain poorly understood. To understand how CLN3 loss affects cellular signaling, we generated human CLN3 knock-out cells (CLN3-KO) and performed RNA-seq analysis. Our multi-dimensional analysis reveals the transcriptional regulator YAP1 as a key factor in remodeling the transcriptome in CLN3-KO cells. YAP1-mediated pro-apoptotic signaling is also increased as a consequence of CLN3 functional loss in retinal pigment …

Multisite Assembly Of Gateway Induced Clones (Magic): A Flexible Cloning Toolbox For Use In Vertebrate Model Systems, William B Gillespie, Yuwen Zhang, Oscar E Ruiz, Juan Cerda, Joshua Ortiz-Guzman, Michelle Sherman, Williamson D Turner, Gabrielle Largoza, Lili E Mosser, Esther Fujimoto, Chi-Bin Chien, Kristen M Kwan, Benjamin R Arenkiel, W Patrick Devine, Joshua D Wythe

Duncan NRI Faculty and Staff Publications

Here, we present MultiSite Assembly of Gateway Induced Clones (MAGIC), which leverages Gateway-based recombinatorial cloning technology for rapid, modular assembly of plasmids to facilitate transgenesis in cells and vertebrate animal models. The MAGIC collection of plasmids spans a range of in vitro and in vivo uses, from tools for optically and chemically tunable gene expression, to simultaneous expression of microRNAs and fluorescent reporters, to a suite of distinct subcellular compartmental fluorescent reporters, to Cre and Dre recombinase-dependent gene expression. MAGIC system components are compatible with existing MultiSite Gateway Tol2 systems currently used in zebrafish and mammalian lentiviral and adenoviral Destination …

Pkr-Driven Isr Signaling Controls Synaptic Translation And Structural Plasticity In An Age-Dependent Manner, Nicolás W Martínez, Felipe Gómez, Ariel Tapia-Godoy, Juan Francisco Roa, Fernanda Moreso-Contreras, Yuwei Liu, Claudia Jara, Cheril Tapia-Rojas, Iván Alfaro, Mauro Costa-Mattioli, Soledad Matus

Faculty, Staff and Students Publications

The integrated stress response (ISR) modulates protein homeostasis in response to both intracellular and extracellular signals. The four kinases involved in the ISR all phosphorylate the same target, the alpha subunit of eukaryotic initiation factor 2 (eIF2α), to integrate various stress signals, thereby regulating cell fate. The activation of the ISR reprograms the proteome by inhibiting general protein synthesis while increasing the translation of specific mRNAs. In the brain, the ISR regulates the type of synaptic plasticity necessary for forming long-term memory. More importantly, the activation of the ISR has emerged as a causal mechanism underlying cognitive decline associated with …

Sensory-Selective Peripheral And Neuraxial Nerve Blockade With 2',6'-Pipecoloxylidide, Claire A Ostertag-Hill, Shuanglong Chen, Tianrui Xue, Rachelle Shao, Matthew Torre, Bin Feng, Zahra Vahedi, Longtu Chen, Steven J Staffa, Yueqin Zheng, Daniel S Kohane

Duncan NRI Faculty and Staff Publications

Background: Safe sensory-selective local anesthetics would be a major advance in the management of acute and chronic pain. This articles describes the sensory-selective local anesthetic properties and the toxicity profile of a known metabolite of amino-amide local anesthetics, 2',6'-pipecoloxylidide (PPX).

Methods: PPX was synthesized and made into its hydrochloride salt. PPX or ropivacaine (ROP) were injected at the sciatic nerve or intrathecally in rats, who then underwent modified hotplate (sensory) testing and weight-bearing (motor) testing. Rats injected with PPX or ROP were assessed for clinical toxicity endpoints. Conduction blockade was studied with single-unit recordings in mice. Biocompatibility was assessed histologically. …

Injectable Microparticle-Nanoliposome Hydrogel For Extended Release Of Small Hydrophilic Molecules, Gil Aizik, Wonmin Choi, Claire A Ostertag-Hill, Matthew Torre, Daniel S Kohane

Duncan NRI Faculty and Staff Publications

Achieving sustained local release of small hydrophilic drugs is challenging and is particularly important when the drugs are toxic. To address these challenges, we developed a hybrid system comprising drug-containing microparticles embedded within a nanoliposomal hydrogel matrix. This system forms through salt-induced gelation using physiologically relevant sodium chloride concentrations (0.9%), allowing for microparticle encapsulation without harsh chemical processes. In vitro, the hybrid system exhibited a slower release of encapsulated cargo compared to microparticles or hydrogel alone. In vivo proof of principle was provided with tetrodotoxin (TTX), a small hydrophilic and ultrapotent local anesthetic, which can cause systemic toxicity if the …

Biliverdin Reductase A Is A Major Determinant Of Protective Nrf2 Signaling, Chirag Vasavda, Ruchita Kothari, Navneet Ammal Kaidery, Suwarna Chakraborty, Sunil Jamuna Tripathi, Ryan S Dhindsa, Cristina Ricco, Shruthi Shanmukha, Samaneh Saberi, Julia E Lefler, Priyanka Kothari, Kalyani Chaubey, Adele M Snowman, Michael C Ostrowski, Eugenio Barone, Lakshminarayan M Iyer, L Aravind, Sudarshana M Sharma, Andrew A Pieper, Bobby Thomas, Solomon H Snyder, Bindu D Paul

Duncan NRI Faculty and Staff Publications

Biliverdin reductase A (BVRA), the terminal enzyme in heme catabolism, generates the neuroprotective and lipophilic antioxidant bilirubin. Here, we identify a nonenzymatic role for BVRA in redox regulation. Through phylogenetic, genetic, biochemical, and enzymatic assays, we found that BVRA exerts critical nonenzymatic antioxidant activity. Transcriptomic analyses further revealed that BVRA physically and genetically interacts with nuclear factor erythroid-derived factor-like 2 (NRF2), a major transcriptional regulator of cellular redox signaling. ChIP-seq and RNA-seq analyses reveal that BVRA and NRF2 coordinate the expression of antioxidant genes, many of which are typically dysregulated in neurodegenerative conditions such as Alzheimer's disease. Thus, this noncanonical …

Atg Conjugation-Dependent/Independent Mechanisms Underlie Lysosomal Stress-Induced Tfeb Regulation, Shiori Akayama, Takayuki Shima, Tatsuya Kaminishi, Mengying Cui, Jlenia Monfregola, Kohei Nishino, Andrea Ballabio, Hidetaka Kosako, Tamotsu Yoshimori, Shuhei Nakamura

Duncan NRI Faculty and Staff Publications

TFEB, a master regulator of autophagy and lysosomal biogenesis, is activated by several cellular stresses including lysosomal damage, but its underlying mechanism is unclear. TFEB activation during lysosomal damage depends on the ATG conjugation system, which mediates lipidation of ATG8 proteins. Here, we newly identify ATG conjugation-independent TFEB regulation that precedes ATG conjugation-dependent regulation, designated Modes I and II, respectively. We reveal unique regulators of TFEB in each mode: APEX1 in Mode I and CCT7 and/or TRIP6 in Mode II. APEX1 interacts with TFEB independently of the ATG conjugation system, and is required for TFEB stability, while both CCT7 and …

Hydrogen Sulfide Inhibits Recruitment Of Monocyte-Derived Tumor Associated Macrophages In Glioblastoma By Downregulating Cxcl12, Joseph Camarano, Morgan Roque, Gabrielle Gahn, Stephen Garrett Whipple, Danielle Terrell, Charles Ronkon, Jamie Toms, Anthony Sin, Bharat Guthikonda, Khatri Latha, Yuhui Yang, Xinggui Shen, Christopher G Kevil, Ganesh Rao, Sungho Lee

Faculty, Staff and Students Publications

Tumor associated macrophages (TAMs) directly contribute to the dismal prognosis of glioblastoma by preventing anti-tumor immunity and promoting tumor invasion and angiogenesis. Inhibiting TAM infiltration is a potential therapeutic strategy in glioblastoma, with several chemokine antagonists in early clinical development. Hydrogen sulfide, a gasotransmitter that regulates microglial accumulation in a wide range of CNS diseases, may be a novel therapeutic target to prevent TAM recruitment in glioblastoma. In this study, hydrogen sulfide concentrations were directly measured from 14 isocitrate dehydrogenase (IDH)-wildtype glioblastoma surgical samples and compared against overall survival as well as expression of TAM markers and chemokines. Effects of …

Carbonic Anhydrase Inhibition Sensitizes Group 3 Medulloblastoma To Radiotherapy, Cory M Richman, Alexandra Rasnitsyn, Borja L Holgado, Maria Vladoiu, Namal Abeysundara, Sandra Majo, Sara Chabi, Lucie J Taunay, Hiromichi Suzuki, Ichiyo Shibahara, Joonas Haapasalo, Jonelle G Pallotta, Tajana Douglas, Kaitlin Kharas, Kyle Juraschka, Oliver Ocsenas, Sachin A Kumar, Kristiina Nordfors, Ana Guerreiro Stücklin, Raul A Suarez, Jiao Zhang, Xiaochong Wu, Craig Daniels, Livia Garzia, Jüri Reimand, Olivier Saulnier, Thomas E Merchant, Celio Pouponnot, David R Raleigh, Michael D Taylor, Pasqualino De Antonellis

Faculty, Staff and Students Publications

Group 3 (G3) medulloblastoma constitutes the most aggressive molecular subgroup, and nearly all patients present with metastases upon recurrence. Treatment for newly diagnosed medulloblastoma relies on a combination of maximal safe surgical resection, followed by chemotherapy and ionizing radiation, and no therapies have been shown to confer a survival benefit at the time of recurrence. Given the limited therapeutic options available for patients with medulloblastoma, especially at recurrence, and the incomplete understanding of the molecular mechanisms underlying resistance to treatment, we sought to uncover actionable targets and biomarkers that could help refine patient selection and treatment of newly diagnosed medulloblastoma …

Kmt2d Temporally Activates Neuronal Transcriptional Factor Genes To Mediate Cerebellar Granule Cell Differentiation, Shilpa S Dhar, Kyung-Pil Ko, Jinho Jang, Calena Brown-Abel, Tao Lin, Sharad Awasthi, Kaifu Chen, Roy V Sillitoe, Jae-Il Park, Min Gyu Lee

Duncan NRI Faculty and Staff Publications

Spatiotemporal gene expression is the fundamental feature of cellular differentiation, including neuron differentiation. The epigenetic mechanism underlying spatiotemporal gene regulation during in vivo neuron differentiation remains largely unknown. Granule cells (GCs) constitute the vast majority of neurons in the cerebellum, which contains most of neurons in the brain. Here, we show that

Adsl Deficiency Is A Secondary Mitochondrial Disease Affecting Organelle Homeostasis And Erk2/Akt Signaling In A Linear Genotype-Phenotype Relation, Matteo Bordi, Beatrice Testa, Claudia Compagnucci, Fiorella Colasuonno, Francesca Cipressa, Elisabetta Betterini, Andrea Mancini, Claudia Carsetti, Illari Salvatori, Caterina Ferraina, Ming Yang, Rossella De Cegli, Eugenio Del Prete, Chiara Veroni, Salvatore Rizza, Sofia Mauri, Elena Ziviani, Marina Macchiaiolo, Davide Vecchio, Filippo Maria Panfili, Teresa Rizza, Gerrit Weber, Rosalba Carrozzo, Alberto Ferri, Silvia Campello, Andrea Ballabio, Christian Frezza, Gianluca Cestra, Marco Tartaglia, Andrea Bartuli, Francesco Cecconi

Duncan NRI Faculty and Staff Publications

Adenylosuccinate lyase deficiency (ADSLd) is a rare autosomal recessive purine metabolism disorder with several clinical manifestations. While toxic substrate accumulation is a known hallmark, no additional molecular mechanisms have been established. Here, we show that ADSLd is associated with mitochondrial dysfunction, including increased fragmentation, impaired respiration, and reduced ATP production. The severity of mitochondrial impairment correlates with ADSLd pathology, especially in mitochondria-dependent tissues. We also identify defects in mitochondrial dynamics and transport linked to ERK2 and AKT suppression. Notably, overexpressing constitutively active ERK2 or supplementing purine intermediates partially rescues the mitochondrial phenotype. These findings suggest an alternative disease mechanism and …

Blue-Shifted Ancyromonad Channelrhodopsins For Multiplex Optogenetics, Elena G Govorunova, Oleg A Sineshchekov, Hai Li, Yueyang Gou, Hongmei Chen, Shuyuan Yang, Yumei Wang, Stephen Mitchell, Alyssa Palmateer, Leonid S Brown, François St-Pierre, Mingshan Xue, John L Spudich

Duncan NRI Faculty and Staff Publications

Light-gated ion channels from protists (channelrhodopsins or ChRs) are optogenetic tools widely used for controlling neurons and cardiomyocytes. Multiplex optogenetic applications require spectrally separated molecules, which are difficult to engineer without disrupting channel function. Scanning numerous sequence databases, we identified three naturally blue-shifted ChRs from ancyromonads. They form a separate branch on the phylogenetic tree and contain residue motifs characteristic of anion ChRs (ACRs). However, only two conduct chloride, whereas the closely related Nutomonas longa homolog generates inward cation currents in mammalian cells under physiological conditions, significantly exceeding those by previously known tools with similar spectral maxima (peak absorption at …

Developmental Transformations Of Purkinje Cells Tracked By Dna Electrokinetic Mobility, Cheryl Brandenburg, Garrett W Crutcher, Andrea J Romanowski, Sarah G Donofrio, Lita R Duraine, Richard N A Owusu-Mensah, Benjamin H Cooper, Izumi Sugihara, Gene J Blatt, Roy V Sillitoe, Alexandros Poulopoulos

Duncan NRI Faculty and Staff Publications

Brain development begins with neurogenesis in progenitor zones and ends with expansive, intricately-patterned cellular diversity in the adult brain. We took advantage of bioelectric interactions between DNA and embryonic tissue to perform "stereo-tracking," a developmental targeting strategy that differentially labels cells at different depths within progenitor zones. This 3D labeling was achieved by delivery of plasmids with distinct electrokinetic mobilities in utero. We applied stereo-tracking with light sheet imaging in the cerebellum and identified that Purkinje cells follow embryonically committed developmental trajectories, linking distinct progenitor zone subfields to the mature topography of the cerebellar cortex. We additionally identified an unexpected …