Neurology Commons^™

Tfeb And Tfe3 Control Glucose Homeostasis By Regulating Insulin Gene Expression, Adrien Pasquier, Nunzia Pastore, Luca D'Orsi, Rita Colonna, Alessandra Esposito, Veronica Maffia, Rossella De Cegli, Margherita Mutarelli, Susanna Ambrosio, Gennaro Tufano, Antonio Grimaldi, Marcella Cesana, Davide Cacchiarelli, Nathalie Delalleau, Gennaro Napolitano, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

To fulfill their function, pancreatic beta cells require precise nutrient-sensing mechanisms that control insulin production. Transcription factor EB (TFEB) and its homolog TFE3 have emerged as crucial regulators of the adaptive response of cell metabolism to environmental cues. Here, we show that TFEB and TFE3 regulate beta-cell function and insulin gene expression in response to variations in nutrient availability. We found that nutrient deprivation in beta cells promoted TFEB/TFE3 activation, which resulted in suppression of insulin gene expression. TFEB overexpression was sufficient to inhibit insulin transcription, whereas beta cells depleted of both TFEB and TFE3 failed to suppress insulin gene …

Dicarboxylic Acylcarnitine Biomarkers In Peroxisome Biogenesis Disorders, Michael F Wangler, Barbara Lesko, Rejwi Dahal, Sharayu Jangam, Pradnya Bhadane, Theodore E Wilson, Molly Mcpheron, Marcus J Miller

Duncan NRI Faculty and Staff Publications

The peroxisome is an essential eukaryotic organelle with diverse metabolic functions. Inherited peroxisomal disorders are associated with a wide spectrum of clinical outcomes and are broadly divided into two classes, those impacting peroxisome biogenesis (PBD) and those impacting specific peroxisomal factors. Prior studies have indicated a role for acylcarnitine testing in the diagnosis of some peroxisomal diseases through the detection of long chain dicarboxylic acylcarnitine abnormalities (C16-DC and C18-DC). However, there remains limited independent corroboration of these initial findings and acylcarnitine testing for peroxisomal diseases has not been widely adopted in clinical laboratories. To explore the utility of acylcarnitine testing …

The Atoh1-Cre Knock-In Allele Ectopically Labels A Subpopulation Of Amacrine Cells And Bipolar Cells In Mouse Retina, Sih-Rong Wu, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

The retina has diverse neuronal cell types derived from a common pool of retinal progenitors. Many molecular drivers, mostly transcription factors, have been identified to promote different cell fates. In Drosophila, atonal is required for specifying photoreceptors. In mice, there are two closely related atonal homologs, Atoh1 and Atoh7. While Atoh7 is known to promote the genesis of retinal ganglion cells, there is no study on the function of Atoh1 in retinal development. Here, we crossed Atoh1^Cre/+ mice to mice carrying a Cre-dependent TdTomato reporter to track potential Atoh1-lineage neurons in retinas. We characterized a heterogeneous …

Rna-Based Translation Activators For Targeted Gene Upregulation, Yang Cao, Huachun Liu, Shannon S Lu, Krysten A Jones, Anitha P Govind, Okunola Jeyifous, Christine Q Simmons, Negar Tabatabaei, William N Green, Jimmy L Holder, Soroush Tahmasebi, Alfred L George, Bryan C Dickinson

Duncan NRI Faculty and Staff Publications

Technologies capable of programmable translation activation offer strategies to develop therapeutics for diseases caused by insufficient gene expression. Here, we present "translation-activating RNAs" (taRNAs), a bifunctional RNA-based molecular technology that binds to a specific mRNA of interest and directly upregulates its translation. taRNAs are constructed from a variety of viral or mammalian RNA internal ribosome entry sites (IRESs) and upregulate translation for a suite of target mRNAs. We minimize the taRNA scaffold to 94 nucleotides, identify two translation initiation factor proteins responsible for taRNA activity, and validate the technology by amplifying SYNGAP1 expression, a haploinsufficiency disease target, in patient-derived cells. …

Clinical Genome Sequencing: Three Years’ Experience At A Tertiary Children’S Hospital, Runjun D Kumar, Lisa F Saba, Haley Streff, Chad A Shaw, Elizabeth Mizerik, Matthew T Snyder, Dolores Lopez-Terrada, Jennifer Scull

Duncan NRI Faculty and Staff Publications

Purpose: Genome sequencing (GS) may shorten the diagnostic odyssey for patients, but clinical experience with this assay in nonresearch settings remains limited. Texas Children's Hospital began offering GS as a clinical test to admitted patients in 2020, providing an opportunity to study GS utilization, possibilities for test optimization, and testing outcomes.

Methods: We retrospectively reviewed GS orders for admitted patients for a nearly 3-year period from March 2020 through December 2022. We gathered anonymized clinical data from the electronic health record to answer the study questions.

Results: The diagnostic yield over 97 admitted patients was 35%. The majority of GS …

Hematopoietic Stem And Progenitor Cells Confer Cross-Protective Trained Immunity In Mouse Models, Bailee N Kain, Brandon T Tran, Pamela N Luna, Ruoqiong Cao, Duy T Le, Marcus A Florez, Laure Maneix, Jack D Toups, Daniel E Morales-Mantilla, Scott Koh, Hyojeong Han, Roman Jaksik, Yun Huang, Andre Catic, Chad A Shaw, Katherine Y King

Duncan NRI Faculty and Staff Publications

Recent studies suggest that infection reprograms hematopoietic stem and progenitor cells (HSPCs) to enhance innate immune responses upon secondary infectious challenge, a process called “trained immunity.” However, the specificity and cell types responsible for this response remain poorly defined. We established a model of trained immunity in mice in response to Mycobacterium avium infection. scRNA-seq analysis revealed that HSPCs activate interferon gamma-response genes heterogeneously upon primary challenge, while rare cell populations expand. Macrophages derived from trained HSPCs demonstrated enhanced bacterial killing and metabolism, and a single dose of recombinant interferon gamma exposure was sufficient to induce similar training. Mice transplanted …

Labeling Piezo2 Activity In The Peripheral Nervous System, Nicholas W Villarino, Yasmeen M F Hamed, Britya Ghosh, Adrienne E Dubin, Amanda H Lewis, Max A Odem, Meaghan C Loud, Yu Wang, M Rocio Servin-Vences, Ardem Patapoutian, Kara L Marshall

Duncan NRI Faculty and Staff Publications

Sensory neurons detect mechanical forces from both the environment and internal organs to regulate physiology. PIEZO2 is a mechanosensory ion channel critical for touch, proprioception, and bladder stretch sensation, yet its broad expression in sensory neurons suggests it has undiscovered physiological roles. To fully understand mechanosensory physiology, we must know where and when PIEZO2-expressing neurons detect force. The fluorescent styryl dye FM 1-43 was previously shown to label sensory neurons. Surprisingly, we find that the vast majority of FM 1-43 somatosensory neuron labeling in mice in vivo is dependent on PIEZO2 activity within the peripheral nerve endings. We illustrate the …

Piezo2 In Somatosensory Neurons Controls Gastrointestinal Transit, M Rocio Servin-Vences, Ruby M Lam, Alize Koolen, Yu Wang, Dimah N Saade, Meaghan Loud, Halil Kacmaz, Suzanne Frausto, Yunxiao Zhang, Arthur Beyder, Kara L Marshall, Carsten G Bönnemann, Alexander T Chesler, Ardem Patapoutian

Duncan NRI Faculty and Staff Publications

The gastrointestinal tract is in a state of constant motion. These movements are tightly regulated by the presence of food and help digestion by mechanically breaking down and propelling gut content. Mechanical sensing in the gut is thought to be essential for regulating motility; however, the identity of the neuronal populations, the molecules involved, and the functional consequences of this sensation are unknown. Here, we show that humans lacking PIEZO2 exhibit impaired bowel sensation and motility. Piezo2 in mouse dorsal root, but not nodose ganglia is required to sense gut content, and this activity slows down food transit rates in …

Cerebellar Dysfunction As A Source Of Dystonic Phenotypes In Mice, Amanda M Brown, Meike E Van Der Heijden, H A Jinnah, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

There is now a substantial amount of compelling evidence demonstrating that the cerebellum may be a central locus in dystonia pathogenesis. Studies using spontaneous genetic mutations in rats and mice, engineered genetic alleles in mice, shRNA knockdown in mice, and conditional genetic silencing of fast neurotransmission in mice have all uncovered a common set of behavioral and electrophysiological defects that point to cerebellar cortical and cerebellar nuclei dysfunction as a source of dystonic phenotypes. Here, we revisit the Ptf1aCre/+;Vglut2flox/flox mutant mouse to define fundamental phenotypes and measures that are valuable for testing the cellular, circuit, and …

The Cerebellum Contributes To Generalized Seizures By Altering Activity In The Ventral Posteromedial Nucleus, Jaclyn Beckinghausen, Joshua Ortiz-Guzman, Tao Lin, Benjamin Bachman, Luis E Salazar Leon, Yu Liu, Detlef H Heck, Benjamin R Arenkiel, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Thalamo-cortical networks are central to seizures, yet it is unclear how these circuits initiate seizures. We test whether a facial region of the thalamus, the ventral posteromedial nucleus (VPM), is a source of generalized, convulsive motor seizures and if convergent VPM input drives the behavior. To address this question, we devise an in vivo optogenetic mouse model to elicit convulsive motor seizures by driving these inputs and perform single-unit recordings during awake, convulsive seizures to define the local activity of thalamic neurons before, during, and after seizure onset. We find dynamic activity with biphasic properties, raising the possibility that heterogenous …

Loss Of The Batten Disease Protein Cln3 Leads To Mis-Trafficking Of M6pr And Defective Autophagic-Lysosomal Reformation, Alessia Calcagni', Leopoldo Staiano, Nicolina Zampelli, Nadia Minopoli, Niculin J Herz, Giuseppe Di Tullio, Tuong Huynh, Jlenia Monfregola, Alessandra Esposito, Carmine Cirillo, Aleksandar Bajic, Mahla Zahabiyon, Rachel Curnock, Elena Polishchuk, Luke Parkitny, Diego Luis Medina, Nunzia Pastore, Peter J Cullen, Giancarlo Parenti, Maria Antonietta De Matteis, Paolo Grumati, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

Batten disease, one of the most devastating types of neurodegenerative lysosomal storage disorders, is caused by mutations in CLN3. Here, we show that CLN3 is a vesicular trafficking hub connecting the Golgi and lysosome compartments. Proteomic analysis reveals that CLN3 interacts with several endo-lysosomal trafficking proteins, including the cation-independent mannose 6 phosphate receptor (CI-M6PR), which coordinates the targeting of lysosomal enzymes to lysosomes. CLN3 depletion results in mis-trafficking of CI-M6PR, mis-sorting of lysosomal enzymes, and defective autophagic lysosomal reformation. Conversely, CLN3 overexpression promotes the formation of multiple lysosomal tubules, which are autophagy and CI-M6PR-dependent, generating newly formed proto-lysosomes. Together, our …

Reprogramming Tumour-Associated Macrophages To Outcompete Cancer Cells, Xian Zhang, Shun Li, Isha Malik, Mytrang H Do, Liangliang Ji, Chun Chou, Wei Shi, Kristelle J Capistrano, Jing Zhang, Ting-Wei Hsu, Briana G Nixon, Ke Xu, Xinxin Wang, Andrea Ballabio, Laura S Schmidt, W Marston Linehan, Ming O Li

Duncan NRI Faculty and Staff Publications

In metazoan organisms, cell competition acts as a quality control mechanism to eliminate unfit cells in favour of their more robust neighbours1,2. This mechanism has the potential to be maladapted, promoting the selection of aggressive cancer cells3-6. Tumours are metabolically active and are populated by stroma cells7,8, but how environmental factors affect cancer cell competition remains largely unknown. Here we show that tumour-associated macrophages (TAMs) can be dietarily or genetically reprogrammed to outcompete MYC-overexpressing cancer cells. In a mouse model of breast cancer, MYC overexpression resulted in an mTORC1-dependent 'winner' cancer cell state. A low-protein diet inhibited mTORC1 signalling in …

Aging Fly Cell Atlas Identifies Exhaustive Aging Features At Cellular Resolution, Tzu-Chiao Lu, Maria Brbić, Ye-Jin Park, Tyler Jackson, Jiaye Chen, Sai Saroja Kolluru, Yanyan Qi, Nadja Sandra Katheder, Xiaoyu Tracy Cai, Seungjae Lee, Yen-Chung Chen, Niccole Auld, Chung-Yi Liang, Sophia H Ding, Doug Welsch, Samuel D'Souza, Angela Oliveira Pisco, Robert C Jones, Jure Leskovec, Eric C Lai, Hugo J Bellen, Liqun Luo, Heinrich Jasper, Stephen R Quake, Hongjie Li

Duncan NRI Faculty and Staff Publications

Aging is characterized by a decline in tissue function, but the underlying changes at cellular resolution across the organism remain unclear. Here, we present the Aging Fly Cell Atlas, a single-nucleus transcriptomic map of the whole aging Drosophila. We characterize 163 distinct cell types and perform an in-depth analysis of changes in tissue cell composition, gene expression, and cell identities. We further develop aging clock models to predict the fly age and show that ribosomal gene expression is a conserved predictive factor for age. Combining all aging features, we find unique cell type-specific aging patterns. This atlas provides a …

Poly(A)-Binding Protein Is An Ataxin-2 Chaperone That Regulates Biomolecular Condensates, Steven Boeynaems, Yanniv Dorone, Yanrong Zhuang, Victoria Shabardina, Guozhong Huang, Anca Marian, Garam Kim, Anushka Sanyal, Nesli-Ece Şen, Daniel Griffith, Roberto Docampo, Keren Lasker, Iñaki Ruiz-Trillo, Georg Auburger, Alex S Holehouse, Edor Kabashi, Yi Lin, Aaron D Gitler

Duncan NRI Faculty and Staff Publications

Biomolecular condensation underlies the biogenesis of an expanding array of membraneless assemblies, including stress granules (SGs) which form under a variety of cellular stresses. Advances have been made in understanding the molecular grammar of a few scaffold proteins that make up these phases, but how the partitioning of hundreds of SG proteins is regulated remains largely unresolved. While investigating the rules that govern the condensation of ataxin-2, a SG protein implicated in neurodegenerative disease, we unexpectedly identified a short 14aa sequence that acts as a condensation switch and is conserved across the eukaryote lineage. We identify poly(A)-binding proteins as unconventional …

Implication Of Chromosomal Microarray Analysis Prior To In-Utero Repair Of Fetal Open Neural Tube Defect, R Zemet, E Krispin, R M Johnson, N R Kumar, L E Westerfield, S Stover, D G Mann, J Castillo, H A Castillo, A A Nassr, M Sanz Cortes, R Donepudi, J Espinoza, W E Whitehead, M A Belfort, A A Shamshirsaz, I B Van Den Veyver

Duncan NRI Faculty and Staff Publications

Objective: In-utero repair of open neural tube defects (ONTD) is an accepted treatment option with demonstrated superior outcome for eligible patients. While current guidelines recommend genetic testing by chromosomal microarray analysis (CMA) when a major congenital anomaly is detected prenatally, the requirement for an in-utero repair, based on the Management of Myelomeningocele Study (MOMS) criteria, is a normal karyotype. In this study, we aimed to evaluate if CMA should be recommended as a prerequisite for in-utero ONTD repair.

Methods: This was a retrospective cohort study of pregnancies complicated by ONTD that underwent laparotomy-assisted fetoscopic repair or open-hysterotomy fetal surgery at …

De Novo Variants In Mrtfb Have Gain-Of-Function Activity In Drosophila And Are Associated With A Novel Neurodevelopmental Phenotype With Dysmorphic Features, Jonathan C Andrews, Jung-Wan Mok, Oguz Kanca, Sharayu Jangam, Cynthia Tifft, Ellen F Macnamara, Bianca E Russell, Lee-Kai Wang, Undiagnosed Diseases Network, Stanley F Nelson, Hugo J Bellen, Shinya Yamamoto, May Christine V Malicdan, Michael F Wangler

Duncan NRI Faculty and Staff Publications

Purpose: Myocardin-related transcription factor B (MRTFB) is an important transcriptional regulator, which promotes the activity of an estimated 300 genes but is not known to underlie a Mendelian disorder.

Methods: Probands were identified through the efforts of the Undiagnosed Disease Network. Because the MRTFB protein is highly conserved between vertebrate and invertebrate model organisms, we generated a humanized Drosophila model expressing the human MRTFB protein in the same spatial and temporal pattern as the fly gene. Actin binding assays were used to validate the effect of the variants on MRTFB.

Results: Here, we report 2 pediatric probands with de novo …

Glutamatergic Cerebellar Neurons Differentially Contribute To The Acquisition Of Motor And Social Behaviors, Meike E Van Der Heijden, Alejandro G Rey Hipolito, Linda H Kim, Dominic J Kizek, Ross M Perez, Tao Lin, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Insults to the developing cerebellum can cause motor, language, and social deficits. Here, we investigate whether developmental insults to different cerebellar neurons constrain the ability to acquire cerebellar-dependent behaviors. We perturb cerebellar cortical or nuclei neuron function by eliminating glutamatergic neurotransmission during development, and then we measure motor and social behaviors in early postnatal and adult mice. Altering cortical and nuclei neurons impacts postnatal motor control and social vocalizations. Normalizing neurotransmission in cortical neurons but not nuclei neurons restores social behaviors while the motor deficits remain impaired in adults. In contrast, manipulating only a subset of nuclei neurons leaves social …

Ragd Auto-Activating Mutations Impair Mit/Tfe Activity In Kidney Tubulopathy And Cardiomyopathy Syndrome, Irene Sambri, Marco Ferniani, Giulia Campostrini, Marialuisa Testa, Viviana Meraviglia, Mariana E G De Araujo, Ladislav Dokládal, Claudia Vilardo, Jlenia Monfregola, Nicolina Zampelli, Francesca Del Vecchio Blanco, Annalaura Torella, Carolina Ruosi, Simona Fecarotta, Giancarlo Parenti, Leopoldo Staiano, Milena Bellin, Lukas A Huber, Claudio De Virgilio, Francesco Trepiccione, Vincenzo Nigro, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

Heterozygous mutations in the gene encoding RagD GTPase were shown to cause a novel autosomal dominant condition characterized by kidney tubulopathy and cardiomyopathy. We previously demonstrated that RagD, and its paralogue RagC, mediate a non-canonical mTORC1 signaling pathway that inhibits the activity of TFEB and TFE3, transcription factors of the MiT/TFE family and master regulators of lysosomal biogenesis and autophagy. Here we show that RagD mutations causing kidney tubulopathy and cardiomyopathy are "auto- activating", even in the absence of Folliculin, the GAP responsible for RagC/D activation, and cause constitutive phosphorylation of TFEB and TFE3 by mTORC1, without affecting the phosphorylation …

Tfeb And Tfe3 Drive Kidney Cystogenesis And Tumorigenesis, Chiara Di Malta, Angela Zampelli, Letizia Granieri, Claudia Vilardo, Rossella De Cegli, Laura Cinque, Edoardo Nusco, Salvatore Pece, Daniela Tosoni, Francesca Sanguedolce, Nicolina Cristina Sorrentino, Maria J Merino, Deborah Nielsen, Ramaprasad Srinivasan, Mark W Ball, Christopher J Ricketts, Cathy D Vocke, Martin Lang, Baktiar Karim, Luisa Lanfrancone, Laura S Schmidt, W Marston Linehan, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

Birt-Hogg-Dubé (BHD) syndrome is an inherited familial cancer syndrome characterized by the development of cutaneous lesions, pulmonary cysts, renal tumors and cysts and caused by loss-of-function pathogenic variants in the gene encoding the tumor-suppressor protein folliculin (FLCN). FLCN acts as a negative regulator of TFEB and TFE3 transcription factors, master controllers of lysosomal biogenesis and autophagy, by enabling their phosphorylation by the mechanistic Target Of Rapamycin Complex 1 (mTORC1). We have previously shown that deletion of Tfeb rescued the renal cystic phenotype of kidney-specific Flcn KO mice. Using Flcn/Tfeb/Tfe3 double and triple KO mice, we now show that both Tfeb …

Glia-Neuron Coupling Via A Bipartite Sialylation Pathway Promotes Neural Transmission And Stress Tolerance Iglia-Neuron Coupling Via A Bipartite Sialylation Pathway Promotes Neural Transmission And Stress Tolerance In Drosophila, Hilary Scott, Boris Novikov, Berrak Ugur, Brooke Allen, Ilya Mertsalov, Pedro Monagas-Valentin, Melissa Koff, Sarah Baas Robinson, Kazuhiro Aoki, Raisa Veizaj, Dirk J Lefeber, Michael Tiemeyer, Hugo Bellen, Vladislav Panin

Duncan NRI Faculty and Staff Publications

Modification by sialylated glycans can affect protein functions, underlying mechanisms that control animal development and physiology. Sialylation relies on a dedicated pathway involving evolutionarily conserved enzymes, including CMP-sialic acid synthetase (CSAS) and sialyltransferase (SiaT) that mediate the activation of sialic acid and its transfer onto glycan termini, respectively. In Drosophila, CSAS and DSiaT genes function in the nervous system, affecting neural transmission and excitability. We found that these genes function in different cells: the function of CSAS is restricted to glia, while DSiaT functions in neurons. This partition of the sialylation pathway allows for regulation of neural functions via …

Evolutionarily Conserved Regulators Of Tau Identify Targets For New Therapies, Jiyoen Kim, Maria De Haro, Ismael Al-Ramahi, Lorena Laura Garaicoechea, Hyun-Hwan Jeong, Jun Young Sonn, Bakhos Tadros, Zhandong Liu, Juan Botas, Huda Yahya Zoghbi

Duncan NRI Faculty and Staff Publications

Tauopathies are neurodegenerative diseases that involve the pathological accumulation of tau proteins; in this family are Alzheimer disease, corticobasal degeneration, and chronic traumatic encephalopathy, among others. Hypothesizing that reducing this accumulation could mitigate pathogenesis, we performed a cross-species genetic screen targeting 6,600 potentially druggable genes in human cells and Drosophila. We found and validated 83 hits in cells and further validated 11 hits in the mouse brain. Three of these hits (USP7, RNF130, and RNF149) converge on the C terminus of Hsc70-interacting protein (CHIP) to regulate tau levels, highlighting the role of CHIP in maintaining tau proteostasis in the brain. …

New Mouse Models With Hypomorphic Sumf1 Variants Mimic Attenuated Forms Of Multiple Sulfatase Deficiency, Nicolina Cristina Sorrentino, Maximiliano Presa, Sergio Attanasio, Vincenzo Cacace, Martina Sofia, Aamir Zuberi, Jennifer Ryan, Somdatta Ray, Igor Petkovic, Karthikeyan Radhakrishnan, Lars Schlotawa, Andrea Ballabio, Cathleen Lutz, Nicola Brunetti-Pierri

Duncan NRI Faculty and Staff Publications

Multiple sulfatase deficiency (MSD) is an ultrarare lysosomal storage disorder due to deficiency of all known sulfatases. MSD is caused by mutations in the Sulfatase Modifying Factor 1 (SUMF1) gene encoding the enzyme responsible for the post-translational modification and activation of all sulfatases. Most MSD patients carry hypomorph SUMF1 variants resulting in variable degrees of residual sulfatase activities. In contrast, Sumf1 null mice with complete deficiency in all sulfatase enzyme activities, have very short lifespan with significant pre-wean lethality, owing to a challenging preclinical model. To overcome this limitation, we genetically engineered and characterized in mice two commonly …

Egr1 Drives Cell Proliferation By Directly Stimulating Tfeb Transcription In Response To Starvation, Marcella Cesana, Gennaro Tufano, Francesco Panariello, Nicolina Zampelli, Susanna Ambrosio, Rossella De Cegli, Margherita Mutarelli, Lorenzo Vaccaro, Micheal J Ziller, Davide Cacchiarelli, Diego L Medina, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

The stress-responsive transcription factor EB (TFEB) is a master controller of lysosomal biogenesis and autophagy and plays a major role in several cancer-associated diseases. TFEB is regulated at the posttranslational level by the nutrient-sensitive kinase complex mTORC1. However, little is known about the regulation of TFEB transcription. Here, through integrative genomic approaches, we identify the immediate-early gene EGR1 as a positive transcriptional regulator of TFEB expression in human cells and demonstrate that, in the absence of EGR1, TFEB-mediated transcriptional response to starvation is impaired. Remarkably, both genetic and pharmacological inhibition of EGR1, using the MEK1/2 inhibitor Trametinib, significantly reduced the …

Tfeb-Mediated Lysosomal Exocytosis Alleviates High-Fat Diet-Induced Lipotoxicity In The Kidney, Jun Nakamura, Takeshi Yamamoto, Yoshitsugu Takabatake, Tomoko Namba-Hamano, Satoshi Minami, Atsushi Takahashi, Jun Matsuda, Shinsuke Sakai, Hiroaki Yonishi, Shihomi Maeda, Sho Matsui, Isao Matsui, Takayuki Hamano, Masatomo Takahashi, Maiko Goto, Yoshihiro Izumi, Takeshi Bamba, Miwa Sasai, Masahiro Yamamoto, Taiji Matsusaka, Fumio Niimura, Motoko Yanagita, Shuhei Nakamura, Tamotsu Yoshimori, Andrea Ballabio, Yoshitaka Isaka

Duncan NRI Faculty and Staff Publications

Obesity is a major risk factor for end-stage kidney disease. We previously found that lysosomal dysfunction and impaired autophagic flux contribute to lipotoxicity in obesity-related kidney disease, in both humans and experimental animal models. However, the regulatory factors involved in countering renal lipotoxicity are largely unknown. Here, we found that palmitic acid strongly promoted dephosphorylation and nuclear translocation of transcription factor EB (TFEB) by inhibiting the mechanistic target of rapamycin kinase complex 1 pathway in a Rag GTPase-dependent manner, though these effects gradually diminished after extended treatment. We then investigated the role of TFEB in the pathogenesis of obesity-related kidney …

Decreasing Mutant Atxn1 Nuclear Localization Improves A Spectrum Of Sca1-Like Phenotypes And Brain Region Transcriptomic Profiles, Hillary P Handler, Lisa Duvick, Jason S Mitchell, Marija Cvetanovic, Molly Reighard, Alyssa Soles, Kathleen B Mather, Orion Rainwater, Shannah Serres, Tessa Nichols-Meade, Stephanie L Coffin, Yun You, Brian L Ruis, Brennon O'Callaghan, Christine Henzler, Huda Y Zoghbi, Harry T Orr

Duncan NRI Faculty and Staff Publications

Spinocerebellar ataxia type 1 (SCA1) is a dominant trinucleotide repeat neurodegenerative disease characterized by motor dysfunction, cognitive impairment, and premature death. Degeneration of cerebellar Purkinje cells is a frequent and prominent pathological feature of SCA1. We previously showed that transport of ATXN1 to Purkinje cell nuclei is required for pathology, where mutant ATXN1 alters transcription. To examine the role of ATXN1 nuclear localization broadly in SCA1-like disease pathogenesis, CRISPR-Cas9 was used to develop a mouse with an amino acid alteration (K772T) in the nuclear localization sequence of the expanded ATXN1 protein. Characterization of these mice indicates that proper nuclear localization …

Structure Of The Lysosomal Mtorc1-Tfeb-Rag-Ragulator Megacomplex, Zhicheng Cui, Gennaro Napolitano, Mariana E G De Araujo, Alessandra Esposito, Jlenia Monfregola, Lukas A Huber, Andrea Ballabio, James H Hurley

Duncan NRI Faculty and Staff Publications

The transcription factor TFEB is a master regulator of lysosomal biogenesis and autophagy1. The phosphorylation of TFEB by the mechanistic target of rapamycin complex 1 (mTORC1)2–5 is unique in its mTORC1 substrate recruitment mechanism, which is strictly dependent on the amino acid-mediated activation of the RagC GTPase activating protein FLCN6,7. TFEB lacks the TOR signalling motif responsible for the recruitment of other mTORC1 substrates. We used cryogenic-electron microscopy to determine the structure of TFEB as presented to mTORC1 for phosphorylation, which we refer to as the ‘megacomplex’. Two full Rag–Ragulator complexes …

Antagonistic Effect Of Cyclin-Dependent Kinases And A Calcium-Dependent Phosphatase On Polyglutamine-Expanded Androgen Receptor Toxic Gain Of Function, Diana Piol, Laura Tosatto, Emanuela Zuccaro, Eric N Anderson, Antonella Falconieri, Maria J Polanco, Caterina Marchioretti, Federica Lia, Joseph White, Elisa Bregolin, Giovanni Minervini, Sara Parodi, Xavier Salvatella, Giorgio Arrigoni, Andrea Ballabio, Albert R La Spada, Silvio C E Tosatto, Fabio Sambataro, Diego L Medina, Udai B Pandey, Manuela Basso, Maria Pennuto

Duncan NRI Faculty and Staff Publications

Spinal and bulbar muscular atrophy is caused by polyglutamine (polyQ) expansions in androgen receptor (AR), generating gain-of-function toxicity that may involve phosphorylation. Using cellular and animal models, we investigated what kinases and phosphatases target polyQ-expanded AR, whether polyQ expansions modify AR phosphorylation, and how this contributes to neurodegeneration. Mass spectrometry showed that polyQ expansions preserve native phosphorylation and increase phosphorylation at conserved sites controlling AR stability and transactivation. In small-molecule screening, we identified that CDC25/CDK2 signaling could enhance AR phosphorylation, and the calcium-sensitive phosphatase calcineurin had opposite effects. Pharmacologic and genetic manipulation of these kinases and phosphatases modified polyQ-expanded AR …

The Lysosomal Ragulator Complex Activates Nlrp3 Inflammasome In Vivo Via Hdac6, Kohei Tsujimoto, Tatsunori Jo, Daiki Nagira, Hachiro Konaka, Jeong Hoon Park, Shin-Ichiro Yoshimura, Akinori Ninomiya, Fuminori Sugihara, Takehiro Hirayama, Eri Itotagawa, Yusei Matsuzaki, Yuki Takaichi, Wataru Aoki, Shotaro Saita, Shuhei Nakamura, Andrea Ballabio, Shigeyuki Nada, Masato Okada, Hyota Takamatsu, Atsushi Kumanogoh

Duncan NRI Faculty and Staff Publications

The cellular activation of the NLRP3 inflammasome is spatiotemporally orchestrated by various organelles, but whether lysosomes contribute to this process remains unclear. Here, we show the vital role of the lysosomal membrane-tethered Ragulator complex in NLRP3 inflammasome activation. Deficiency of Lamtor1, an essential component of the Ragulator complex, abrogated NLRP3 inflammasome activation in murine macrophages and human monocytic cells. Myeloid-specific Lamtor1-deficient mice showed marked attenuation of NLRP3-associated inflammatory disease severity, including LPS-induced sepsis, alum-induced peritonitis, and monosodium urate (MSU)-induced arthritis. Mechanistically, Lamtor1 interacted with both NLRP3 and histone deacetylase 6 (HDAC6). HDAC6 enhances the interaction between Lamtor1 and NLRP3, resulting …

Cerebellar Dysfunction In Rodent Models With Dystonia, Tremor, And Ataxia, Meike E Van Der Heijden, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Dystonia is a movement disorder characterized by involuntary co- or over-contractions of the muscles, which results in abnormal postures and movements. These symptoms arise from the pathophysiology of a brain-wide dystonia network. There is mounting evidence suggesting that the cerebellum is a central node in this network. For example, manipulations that target the cerebellum cause dystonic symptoms in mice, and cerebellar neuromodulation reduces these symptoms. Although numerous findings provide insight into dystonia pathophysiology, they also raise further questions. Namely, how does cerebellar pathophysiology cause the diverse motor abnormalities in dystonia, tremor, and ataxia? Here, we describe recent work in rodents …

An Initial Experience Of Completion Hemispherotomy Via Magnetic Resonance-Guided Laser Interstitial Therapy, Vijay M Ravindra, Lucia Ruggieri, Nisha Gadgil, Angela P Addison, Ilana Patino, David D Gonda, Jason Chu, Laura Whitehead, Anne Anderson, Gloria Diaz-Medina, Kimberly Houck, Akshat Katyayan, Laura Masters, Audrey Nath, Michael Quach, James John Riviello, Elaine Seto, Krystal Elizabeth Sully, Latanya Agurs, Sonali Sen, Maureen Handoko, Rohini Coorg, Irfan Ali, Daniel Ikeda, Howard Weiner, Daniel J Curry

Duncan NRI Faculty and Staff Publications

Introduction: In carefully selected patients with medically refractory epilepsy, disconnective hemispherotomy can result in significant seizure freedom; however, incomplete disconnection can result in ongoing seizures and poses a significant challenge. Completion hemispherotomy provides an opportunity to finish the disconnection. We describe the use of magnetic resonance-guided laser interstitial thermal ablation (MRgLITT) for completion hemispherotomy.

Methods: Patients treated with completion hemispherotomy using MRgLITT at our institution were identified. Procedural and seizure outcomes were evaluated retrospectively.

Results: Five patients (3 males) underwent six MRgLITT procedures (one child treated twice) for completion hemispherotomy at a median age of 6 years (range 1.8-12.9). Two …