Neurosciences Commons^™

C-Terminal Frameshift Variants In Gpkow Are Associated With A Multisystemic X-Linked Disorder, Jung-Wan Mok, Laura Mackay, Maria Blazo, Elizabeth Mizerik, Jozef Gecz, Renee Carroll, Mathilde Nizon, Sophie Rondeau, Madeleine Joubert, Silvestre Cuinat, Wallid Deb, Fernanda Valle Sirias, Monika Weisz-Hubshman, Shamika Ketkar, Urszula Polak, Alyssa A Tran, Debra Kearney, Neil A Hanchard, Oguz Kanca, Michael F Wangler, Hugo J Bellen, Brendan H Lee, Shinya Yamamoto, Keren Machol

Duncan NRI Faculty and Staff Publications

Purpose: GPKOW, a gene on the X-chromosome, encodes a nuclear RNA-binding protein important in messenger RNA (mRNA) processing as a spliceosome subunit. This work aims to establish GPKOW as a disease-associated gene.

Methods: We describe 3 males from 2 unrelated families with hemizygous frameshift variants affecting the last exon of GPKOW p.(Arg441SerfsTer30) and p.(Ser444GlufsTer28). The effect of p.(Ser444GlufsTer28) on gene expression was evaluated in patient's fibroblasts. In vivo studies in Drosophila melanogaster targeting the sole GPKOW fly ortholog, CG10324 (Gpkow) were performed.

Results: Clinical presentations included intrauterine growth restriction, microcephaly/microencephaly, and eye, brain, skin, and skeletal abnormalities. Heterozygote females presented …

Formation Of An Expanding Memory Representation In The Hippocampus, Sachin P Vaidya, Guanchun Li, Raymond A Chitwood, Yiding Li, Jeffrey C Magee

Faculty, Staff and Students Publications

How brain networks connected by labile synapses store new information without catastrophically overwriting previous memories remains poorly understood. To examine this, we tracked the same population of hippocampal CA1 place cells (PCs) as mice learned a task for 7 days. We found evidence of memory formation as both the number of PCs maintaining a stable place field and the stability of individual PCs progressively increased across the week until most of the representation was composed of long-term stable PCs. The stable PCs disproportionately represented task-related learned information, were retrieved earlier within a behavioral session and showed a strong correlation with …

Integrating Endocannabinoid Signaling, Cck Interneurons, And Hippocampal Circuit Dynamics In Behaving Animals, Shreya Malhotra, Florian Donneger, Jordan S Farrell, Barna Dudok, Attila Losonczy, Ivan Soltesz

Faculty, Staff and Students Publications

The brain's endocannabinoid signaling system modulates a diverse range of physiological phenomena and is also involved in various psychiatric and neurological disorders. The basic components of the molecular machinery underlying endocannabinoid-mediated synaptic signaling have been known for decades. However, limitations associated with the short-lived nature of endocannabinoid lipid signals had made it challenging to determine the spatiotemporal specificity and dynamics of endocannabinoid signaling in vivo. Here, we discuss how novel technologies have recently enabled unprecedented insights into endocannabinoid signaling taking place at specific synapses in behaving animals. In this review, we primarily focus on cannabinoid-sensitive inhibition in the hippocampus in …

Glutamatergic Regulation Of Mirna-Containing Intraluminal Vesicle Trafficking And Extracellular Vesicle Secretion From Cortical Neurons, Marcela Bertolio, Qiyi Li, Francesca E Mowry, Kathryn E Reynolds, Rashed Alananzeh, Haichao Wei, Kyoeun Keum, Rachel Jarvis, Jiaqian Wu, Yongjie Yang

Faculty, Staff and Student Publications

Neuronal extracellular vesicles (microvesicles and exosomes) are emerging secreted vesicular signals that play important roles in the CNS. Currently, little is known about how glutamatergic signalling affects the subcellular localisation of exosome precursor intraluminal vesicles (ILVs), microRNA (miR) packaging into ILVs and in vivo spreading of neuronal EVs. By selectively labelling ILVs and exosomes (but not plasma membrane-derived MVs) with GFP-tagged human CD63 (hCD63-GFP) in cortical neurons, we found that glutamate stimulation significantly redistributes subcellular localisation of hCD63-GFP+ ILVs, especially decreasing its co-localisation with multi-vesicular body (MVB) marker Rab7 while substantially promoting EV secretion. Interestingly, glutamate stimulation only modestly alters …

Glucagon-Like Peptide-1 Receptor Agonists In Neurodegenerative Diseases: Promises And Challenges, Zhi Dong Zhou, Lingxiao Yi, Karolina Popławska-Domaszewicz, Kallol Ray Chaudhuri, Joseph Jankovic, Eng King Tan

Faculty, Staff and Students Publications

Glucagon-like peptide-1 (GLP-1) receptor agonists (GRA) belong to a class of compounds that reduce blood glucose and energy intake by simulating actions of endogenous incretin hormone GLP-1 after it is released by the gut following food consumption. They are used to treat type 2 diabetes mellitus (T2DM) and obesity and have systemic effects on various organs, including the brain, liver, pancreas, heart, and the gut. Patients with T2DM have a higher risk of developing neurodegenerative diseases (NDs), including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD), accompanied by more severe motor deficits and faster …

The Metastatic Role Of The Cxcl10-Cxcr3 Axis And Its Therapeutic Potential In Osteosarcoma, Benjamin B Gyau, Junyan Wang, Xiang Chen, Margaret A Clement, Zoe D Man, Angela M Major, Mathew C Weiser, Jun Xu, John Hicks, Tsz-Kwong Man

Faculty, Staff and Students Publications

The CXCL10-CXCR3 axis regulates immunity, tumorigenesis, and metastasis in multiple cancers. Yet, its roles in osteosarcoma (OS), the predominant pediatric malignant bone tumor, are not fully defined. Our prior work has shown that elevated serum CXCL10 levels correlate with poor OS prognosis. The current study delves deeper by investigating how CXCL10-mediated CXCR3 signaling influences OS growth and metastatic spread. In vitro, CXCL10 and related CXCR3 ligands (CXCL4, CXCL9, and CXCL11) enhanced OS tumor cell migration. In an orthotopic xenograft mouse model with a newly created CXCR3 knockout (KO) mutant, tumor growth and lung metastasis decreased significantly when compared with …

The Cgas/Sting Pathway: Friend Or Foe In Regulating Cardiomyopathy, Weiyue Wang, Yuanxu Gao, Hyun Kyoung Lee, Albert Cheung-Hoi Yu, Markus Kipp, Hannes Kaddatz, Jiangshan Zhan

Duncan NRI Faculty and Staff Publications

Inflammation is a central hallmark of cardiomyopathy, where misdirected immune responses contribute to chronic myocardial dysfunction. Among the emerging molecular mechanisms implicated in this process, the cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) signaling pathway has garnered increasing attention. Acting as a key cytosolic DNA sensor, the cGAS/STING pathway orchestrates inflammatory responses triggered by microbial infections or endogenous cellular stressors such as autophagy and apoptosis. Despite its pivotal role, the precise molecular mechanisms regulating this pathway and its role in cardiomyopathy-associated inflammation remain poorly understood and subject to ongoing debate. To address this scientific gap, we first reviewed key …

A Hierarchy Of Pdz Domain Scaffolding Proteins Clusters The Kv1 K+ Channel Protein Complex At The Axon Initial Segment, Wei Zhang, Victoria L Palfini, Yu Wu, Xiaoyun Ding, Allison J Melton, Yudong Gao, Yuki Ogawa, Matthew N Rasband

Faculty, Staff and Students Publications

Action potentials are initiated and modulated at the axon initial segment (AIS) by highly clustered ion channels. Voltage-gated Kv1 potassium channels underlie most outward AIS K+ current. AIS Kv1 channels exist in a large protein complex including ADAM22, Caspr2, and LGI1. However, their clustering mechanisms remain unknown. Because Kv1 channels have a highly conserved PDZ-binding motif, we used CRISPR-based genome editing to screen 18 PDZ domain-containing proteins identified in our previous AIS proximity proteome for their AIS localization. Among these, we found that the scaffolding proteins SCRIB and PSD93 are highly enriched at the AIS. Using CRISPR-mediated knockout, cell surface …

Alzheimer’S Disease Protective Allele Of Clusterin Modulates Neuronal Excitability Through Lipid-Droplet-Mediated Neuron-Glia Communication, Xiaojie Zhao, Yan Li, Siwei Zhang, Ari Sudwarts, Hanwen Zhang, Alena Kozlova, Matthew J Moulton, Lindsey D Goodman, Zhiping P Pang, Alan R Sanders, Hugo J Bellen, Gopal Thinakaran, Jubao Duan

Duncan NRI Faculty and Staff Publications

Background: Genome-wide association studies (GWAS) of Alzheimer's disease (AD) have identified a plethora of risk loci. However, the disease variants/genes and the underlying mechanisms have not been extensively studied.

Methods: Bulk ATAC-seq was performed in induced pluripotent stem cells (iPSCs) differentiated various brain cell types to identify allele-specific open chromatin (ASoC) SNPs. CRISPR-Cas9 editing generated isogenic pairs, which were then differentiated into glutamatergic neurons (iGlut). Transcriptomic analysis and functional studies of iGlut co-cultured with mouse astrocytes assessed neuronal excitability and lipid droplet formation.

Results: We identified a putative causal SNP of CLU that impacted neuronal chromatin accessibility to transcription-factor(s), with …

The Small Gtpase Rap1 In Pomc Neurons Regulates Leptin Actions And Glucose Metabolism, Kentaro Kaneko, Weisheng Lu, Yong Xu, Alexei Morozov, Makoto Fukuda

Faculty, Staff and Students Publications

The hypothalamic leptin-proopiomelanocortin (POMC) pathway is critical for regulating metabolism. POMC neurons in the arcuate nucleus respond to leptin and play a pivotal role in mediating energy and glucose balance. However, during diet-induced obesity (DIO), these neurons often develop resistance to exogenous leptin. Recently, the small GTPase Rap1 has been implicated as an inhibitor of neuronal leptin signaling; however, its specific role within POMC neurons remains unexplored. We generated tamoxifen-inducible, POMC neuron-specific Rap1 knockout mice to selectively delete both Rap1a and Rap1b isoforms in POMC neurons. By analyzing these mice through metabolic phenotyping, immunohistochemistry, and biochemical assays, we show that …

Metastatic Medulloblastoma Remodels The Local Leptomeningeal Microenvironment To Promote Further Metastatic Colonization And Growth, Namal Abeysundara, Alexandra Rasnitsyn, Vernon Fong, Alexander Bahcheli, Randy Van Ommeren, Kyle Juraschka, Maria Vladoiu, Winnie Ong, Bryn Livingston, Pasqualino De Antonellis, Michelle Ly, Borja López Holgado, Olga Sirbu, Shahrzad Bahrampour, Hyun-Kee Min, Jerry Fan, Carolina Nor, Abhirami Visvanathan, Jiao Zhang, Hao Wang, Lei Qin, Ning Huang, Jonelle Pallotta, Tajana Douglas, Esta Mak, Haipeng Su, Karen Ng, Kevin Yang Zhang, Craig Daniels, Calixto-Hope G Lucas, Charles G Eberhart, Hailong Liu, Tao Jiang, Faiyaz Notta, Vijay Ramaswamy, Jüri Reimand, Marco Gallo, Jeremy N Rich, Xiaochong Wu, Xi Huang, Michael D Taylor

Faculty, Staff and Students Publications

Leptomeningeal metastases are the major source of morbidity and mortality for patients with medulloblastoma. The biology of the leptomeningeal metastases and the local tumour microenvironment are poorly characterized. Here we show that metastasis-associated meningeal fibroblasts (MB-MAFs) are transcriptionally distinct and signal extensively to tumour cells and the tumour microenvironment. Metastatic cells secrete platelet-derived growth factor (PDGF) ligands into the local microenvironment to chemotactically recruit meningeal fibroblasts. Meningeal fibroblasts are reprogrammed to become MB-MAFs, expressing distinct transcriptomes and secretomes, including bone morphogenetic proteins. Active bone morphogenetic protein signalling and co-implantation of tumour cells with MB-MAFs enhances the colonization of the leptomeninges …

Mapping The Developmental Profile Of Ventricular Zone-Derived Neurons In The Human Cerebellum, Anders W Erickson, Henry Tan, Liam D Hendrikse, Jake Millman, Zachary Thomson, Joseph Golser, Omar Khan, Guanyi He, Kathleen Bach, Arpit Suresh Mishra, Janja Kopic, Zeljka Krsnik, Ferechte Encha-Razavi, Giulia Petrilli, Fabien Guimiot, Evelina Silvestri, Kimberly A Aldinger, Michael D Taylor, Kathleen J Millen, Parthiv Haldipur

Faculty, Staff and Students Publications

The cerebellar ventricular zone (VZ) is the primary source of progenitors that generate cerebellar GABAergic neurons, including Purkinje cells (PCs) and interneurons (INs). This study provides detailed characterization of human cerebellar GABAergic neurogenesis using transcriptomic and histopathological analyses and reveals conserved and unique features compared to rodents. We show that the sequential progression of neurogenesis is conserved and occurs before 8 postconception weeks. Notably, PC differentiation occurs in the outer subventricular zone (SVZ), a region absent in the mouse cerebellum. Human PCs are generated during a compact two-week period before the onset of cerebral cortex histogenesis. A subset of human …

Structural Insights Into The Function, Dysfunction And Modulation Of Kv3 Channels, Manuel Covarrubias, Qiansheng Liang, Linh Nguyen-Phuong, Kyle J. Kennedy, Tyler D. Alexander, Ms, Andrew Sam

Department of Neuroscience Faculty Papers

The third subfamily of voltage-gated K⁺ (Kv) channels includes four members, Kv3.1, Kv3.2, Kv3.3 and Kv3.4. Fast gating and activation at relatively depolarized membrane potentials allows Kv3 channels to be major drivers of fast action potential repolarization in the nervous system. Consequently, they help determine the fast-spiking phenotype of inhibitory interneurons and regulate fast synaptic transmission at glutamatergic synapses and the neuromuscular junction. Recent studies from our group and a team of collaborators have used cryo-EM to demonstrate the surprising gating role of the Kv3.1 cytoplasmic T1 domain, the structural basis of a developmental epileptic encephalopathy caused by the …

A Deep Learning Strategy To Identify Cell Types Across Species From High-Density Extracellular Recordings, Maxime Beau, David J Herzfeld, Francisco Naveros, Marie E Hemelt, Federico D'Agostino, Marlies Oostland, Alvaro Sánchez-López, Young Yoon Chung, Michael Maibach, Stephen Kyranakis, Hannah N Stabb, M Gabriela Martínez Lopera, Agoston Lajko, Marie Zedler, Shogo Ohmae, Nathan J Hall, Beverley A Clark, Dana Cohen, Stephen G Lisberger, Dimitar Kostadinov, Court Hull, Michael Häusser, Javier F Medina

Faculty, Staff and Students Publications

High-density probes allow electrophysiological recordings from many neurons simultaneously across entire brain circuits but fail to reveal cell type. Here, we develop a strategy to identify cell types from extracellular recordings in awake animals and reveal the computational roles of neurons with distinct functional, molecular, and anatomical properties. We combine optogenetics and pharmacology using the cerebellum as a testbed to generate a curated ground-truth library of electrophysiological properties for Purkinje cells, molecular layer interneurons, Golgi cells, and mossy fibers. We train a semi-supervised deep learning classifier that predicts cell types with greater than 95% accuracy based on the waveform, discharge …

Nitrate Ameliorates Alcohol-Induced Cognitive Impairment Via Oral Microbiota, Xiangxue Li, Zhaojun Ni, Weixiong Shi, Kangqing Zhao, Yanjie Zhang, Lina Liu, Zhong Wang, Jie Chen, Zhoulong Yu, Xuejiao Gao, Ying Qin, Jingwen Zhao, Wenjuan Peng, Jie Shi, Thomas R Kosten, Lin Lu, Lei Su, Yanxue Xue, Hongqiang Sun

Faculty, Staff and Students Publications

Alcohol use is associated with cognitive impairment and dysregulated inflammation. Oral nitrate may benefit cognitive impairment in aging through altering the oral microbiota. Similarly, the beneficial effects of nitrate on alcohol-induced cognitive decline and the roles of the oral microbiota merit investigation. Here we found that nitrate supplementation effectively mitigated cognitive impairment induced by chronic alcohol exposure in mice, reducing both systemic and neuroinflammation. Furthermore, nitrate restored the dysbiosis of the oral microbiota caused by alcohol consumption. Notably, removing the oral microbiota led to a subsequent loss of the beneficial effects of nitrate. Oral microbiota from donor alcohol use disordered …

Somatodendritic Orientation Determines Tdcs-Induced Neuromodulation Of Purkinje Cell Activity In Awake Mice, Carlos A Sánchez-León, Guillermo Sánchez-Garrido Campos, Marta Fernández, Álvaro Sánchez-López, Javier F Medina, Javier Márquez-Ruiz

Faculty, Staff and Students Publications

Transcranial direct-current stimulation (tDCS) of the cerebellum is a promising non-invasive neuromodulatory technique being proposed for the treatment of neurological and neuropsychiatric disorders. However, there is a lack of knowledge about how externally applied currents affect neuronal spiking activity in cerebellar circuits in vivo. We investigated how Cb-tDCS affects the firing rate of Purkinje cells (PC) and non-PC in the mouse cerebellar cortex to understand the underlying mechanisms behind the polarity-dependent modulation of neuronal activity induced by tDCS. Mice (n=9) were prepared for the chronic recording of local field potentials (LFPs) to assess the actual electric field gradient imposed by …

The Medial Olivocochlear Efferent Pathway Potentiates Cochlear Amplification In Response To Hearing Loss, Patricia M Quiñones, Michelle Pei, Hemant Srivastava, Ariadna Cobo-Cuan, Marcela A Morán, Bong Jik Kim, Clayton B Walker, Michael J Serafino, Frank Macias-Escriva, Juemei Wang, James B Dewey, Brian E Applegate, Matthew J Mcginley, John S Oghalai

Faculty, Staff and Students Publications

The mammalian cochlea receives efferent feedback from the brain. Many functions for this feedback have been hypothesized, including on short timescales, such as mediating attentional states, and long timescales, such as buffering acoustic trauma. Testing these hypotheses has been impeded by an inability to make direct measurements of efferent effects in awake animals. Here, we assessed the role of the medial olivocochlear (MOC) efferent nerve fibers on cochlear amplification by measuring organ of Corti vibratory responses to sound in both sexes of awake and anesthetized mice. We studied long-term effects by genetically ablating the efferents and/or afferents. Cochlear amplification increased …

An Unsupervised Map Of Excitatory Neuron Dendritic Morphology In The Mouse Visual Cortex, Marissa A Weis, Stelios Papadopoulos, Laura Hansel, Timo Lüddecke, Brendan Celii, Paul G Fahey, Eric Y Wang, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Forrest Collman, Nuno Maçarico Da Costa, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, R Clay Reid, Casey M Schneider-Mizell, H Sebastian Seung, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Wenjing Yin, Szi-Chieh Yu, Jacob Reimer, Philipp Berens, Andreas S Tolias, Alexander S Ecker

Faculty, Staff and Students Publications

Neurons in the neocortex exhibit astonishing morphological diversity, which is critical for properly wiring neural circuits and giving neurons their functional properties. However, the organizational principles underlying this morphological diversity remain an open question. Here, we took a data-driven approach using graph-based machine learning methods to obtain a low-dimensional morphological "bar code" describing more than 30,000 excitatory neurons in mouse visual areas V1, AL, and RL that were reconstructed from the millimeter scale MICrONS serial-section electron microscopy volume. Contrary to previous classifications into discrete morphological types (m-types), our data-driven approach suggests that the morphological landscape of cortical excitatory neurons is …

Life On The Dry Side: A Roadmap To Understanding Desiccation Tolerance And Accelerating Translational Applications, R A Marks, J T B Ekwealor, M A S Artur, L Bondi, T C Boothby, O M S Carmo, D C Centeno, K K Coe, H J W Dace, S Field, A Hutt, S Porembski, A Thalhammer, L Van Der Pas, A J Wood, P Alpert, D Bartels, S Boeynaems, M N Datar, T Giese, W I Seidou, S M Kirchner, J Köhler, U G V S S Kumara, J Kyung, R Lyall, B D Mishler, J B V T Ndongmo, M S Otegui, V Reddy, J Rexroth, S M Tebele, R Vanburen, J Verdier, U C Vothknecht, M F Wittenberg, E Zokov, M J Oliver, S Y Rhee

Duncan NRI Faculty and Staff Publications

To thrive in extreme conditions, organisms have evolved a diverse arsenal of adaptations that confer resilience. These species, their traits, and the mechanisms underlying them comprise a valuable resource that can be mined for numerous conceptual insights and applied objectives. One of the most dramatic adaptations to water limitation is desiccation tolerance. Understanding the mechanisms underlying desiccation tolerance has important potential implications for medicine, biotechnology, agriculture, and conservation. However, progress has been hindered by a lack of standardization across sub-disciplines, complicating the integration of data and slowing the translation of basic discoveries into practical applications. Here, we synthesize current knowledge …

De Novo Variants In Cdkl1 And Cdkl2 Are Associated With Neurodevelopmental Symptoms, Ali H Bereshneh, Jonathan C Andrews, Daniel F Eberl, Guney Bademci, Nicholas A Borja, Stephanie Bivona, Wendy K Chung, Shinya Yamamoto, Michael F Wangler, Shane Mckee, Mustafa Tekin, Hugo J Bellen, Oguz Kanca

Duncan NRI Faculty and Staff Publications

The CDKL (cyclin-dependent kinase-like) family consists of five members in humans, CDKL1-5, that encode serine-threonine kinases. The only member that has been associated with a Mendelian disorder is CDKL5, and variants in CDKL5 cause developmental and epileptic encephalopathy type 2 (DEE2). Here, we study four de novo variants in CDKL2 identified in five individuals, including three unrelated probands and monozygotic twins. These individuals present with overlapping symptoms, including global developmental delay, intellectual disability, childhood-onset epilepsy, dyspraxia, and speech deficits. We also identified two individuals with de novo missense variants in CDKL1 in the published Deciphering Developmental Disorders (DDD) and GeneDx …

Foraging Animals Use Dynamic Bayesian Updating To Model Meta-Uncertainty In Environment Representations, James Webb, Paul Steffan, Benjamin Y Hayden, Daeyeol Lee, Caleb Kemere, Matthew Mcginley

Faculty, Staff and Students Publications

Foraging theory predicts animal behavior in many contexts. In patch-based foraging behaviors, the marginal value theorem (MVT) gives the optimal strategy for deterministic environments whose parameters are fully known to the forager. In natural settings, environmental parameters exhibit variability and are only partially known to the animal based on its experience, creating uncertainty. Models of uncertainty in foraging are well established. However, natural environments also exhibit unpredicted changes in their statistics. As a result, animals must ascertain whether the currently observed quality of the environment is consistent with their internal models, or whether something has changed, creating meta-uncertainty. Behavioral strategies …

Neurd Offers Automated Proofreading And Feature Extraction For Connectomics, Brendan Celii, Stelios Papadopoulos, Zhuokun Ding, Paul G Fahey, Eric Wang, Christos Papadopoulos, Alexander B Kunin, Saumil Patel, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Erick Cobos, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, Casey M Schneider-Mizell, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Szi-Chieh Yu, Wenjing Yin, Daniel Xenes, Lindsey M Kitchell, Patricia K Rivlin, Victoria A Rose, Caitlyn A Bishop, Brock Wester, Emmanouil Froudarakis, Edgar Y Walker, Fabian Sinz, H Sebastian Seung, Forrest Collman, Nuno Maçarico Da Costa, R Clay Reid, Xaq Pitkow, Andreas S Tolias, Jacob Reimer

Faculty, Staff and Students Publications

We are in the era of millimetre-scale electron microscopy volumes collected at nanometre resolution1,2. Dense reconstruction of cellular compartments in these electron microscopy volumes has been enabled by recent advances in machine learning3–6. Automated segmentation methods produce exceptionally accurate reconstructions of cells, but post hoc proofreading is still required to generate large connectomes that are free of merge and split errors. The elaborate 3D meshes of neurons in these volumes contain detailed morphological information at multiple scales, from the diameter, shape and branching patterns of axons and dendrites, down to the fine-scale …

Functional Connectomics Reveals General Wiring Rule In Mouse Visual Cortex, Zhuokun Ding, Paul G Fahey, Stelios Papadopoulos, Eric Y Wang, Brendan Celii, Christos Papadopoulos, Andersen Chang, Alexander B Kunin, Dat Tran, Jiakun Fu, Zhiwei Ding, Saumil Patel, Lydia Ntanavara, Rachel Froebe, Kayla Ponder, Taliah Muhammad, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Erick Cobos, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, Casey M Schneider-Mizell, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Wenjing Yin, Szi-Chieh Yu, Dimitri Yatsenko, Emmanouil Froudarakis, Fabian Sinz, Krešimir Josić, Robert Rosenbaum, H Sebastian Seung, Forrest Collman, Nuno Maçarico Da Costa, R Clay Reid, Edgar Y Walker, Xaq Pitkow, Jacob Reimer, Andreas S Tolias

Faculty, Staff and Students Publications

Understanding the relationship between circuit connectivity and function is crucial for uncovering how the brain computes. In mouse primary visual cortex, excitatory neurons with similar response properties are more likely to be synaptically connected1–8; however, broader connectivity rules remain unknown. Here we leverage the millimetre-scale MICrONS dataset to analyse synaptic connectivity and functional properties of neurons across cortical layers and areas. Our results reveal that neurons with similar response properties are preferentially connected within and across layers and areas—including feedback connections—supporting the universality of ‘like-to-like’ connectivity across the visual hierarchy. Using a validated digital twin model, …

Inhibitory Specificity From A Connectomic Census Of Mouse Visual Cortex, Casey M Schneider-Mizell, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Leila Elabbady, Clare Gamlin, Daniel Kapner, Sam Kinn, Gayathri Mahalingam, Sharmishtaa Seshamani, Shelby Suckow, Marc Takeno, Russel Torres, Wenjing Yin, Sven Dorkenwald, J Alexander Bae, Manuel A Castro, Akhilesh Halageri, Zhen Jia, Chris Jordan, Nico Kemnitz, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, William Silversmith, Nicholas L Turner, William Wong, Jingpeng Wu, Jacob Reimer, Andreas S Tolias, H Sebastian Seung, R Clay Reid, Forrest Collman, Nuno Maçarico Da Costa

Faculty, Staff and Students Publications

Mammalian cortex features a vast diversity of neuronal cell types, each with characteristic anatomical, molecular and functional properties1. Synaptic connectivity shapes how each cell type participates in the cortical circuit, but mapping connectivity rules at the resolution of distinct cell types remains difficult. Here we used millimetre-scale volumetric electron microscopy2 to investigate the connectivity of all inhibitory neurons across a densely segmented neuronal population of 1,352 cells spanning all layers of mouse visual cortex, producing a wiring diagram of inhibition with more than 70,000 synapses. Inspired by classical neuroanatomy, we classified inhibitory neurons based on targeting of …

Glucose Uptake In Pigment Glia Suppresses Tau-Induced Inflammation And Photoreceptor Degeneration, Mikiko Oka, Sho Nakajima, Emiko Suzuki, Shinya Yamamoto, Kanae Ando

Duncan NRI Faculty and Staff Publications

Brain inflammation contributes to the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human MATP (hereafter referred to as Tau) in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by the formation of dark-stained round inclusion-like structures and swelling of the lamina cortex. We found that inclusion-like structures …

De Novo Variants In Rybp Are Associated With A Severe Neurodevelopmental Disorder And Congenital Anomalies, Monika Weisz-Hubshman, Lindsay C Burrage, Sharayu V Jangam, Jill A Rosenfeld, Sandra Von Hardenberg, Anke Bergmann, Manuela Friederike Richter, Malgorzata Rydzanicz, Rafal Ploski, Agnieszka Stembalska, Wendy K Chung, Rebecca R Hernan, Foong Y Lim, Theresa Brunet, Steffen Syrbe, Boris Keren, Solveig Heide, David R Murdock, Hongzheng Dai, Fan Xia, Shamika Ketkar, Brian Dawson, Vinodh Narayanan, Hillary K Graves, Undiagnosed Diseases Network, Michael F Wangler, Carlos Bacino, Brendan Lee

Duncan NRI Faculty and Staff Publications

Purpose: Polycomb group proteins are key epigenetic transcriptional regulators. Multiple neurodevelopmental disorders are associated with pathogenic variants of the genes encoding Polycomb group proteins. RYBP is a core component of the noncanonical Polycomb Repressor Complex 1; however, its role in disease is unclear.

Methods: Functional consequences of RYBP variants were assessed using in vitro cellular and in vivo Drosophila melanogaster studies.

Results: We described 7 individuals with heterozygous de novo variants of RYBP and their clinical findings, including severe developmental delay, dysmorphisms, and multiple congenital anomalies. We showed that all single-nucleotide variants in RYBP localize to the N-terminal domain of …

Foundation Model Of Neural Activity Predicts Response To New Stimulus Types, Eric Y Wang, Paul G Fahey, Zhuokun Ding, Stelios Papadopoulos, Kayla Ponder, Marissa A Weis, Andersen Chang, Taliah Muhammad, Saumil Patel, Zhiwei Ding, Dat Tran, Jiakun Fu, Casey M Schneider-Mizell, Microns Consortium, R Clay Reid, Forrest Collman, Nuno Maçarico Da Costa, Katrin Franke, Alexander S Ecker, Jacob Reimer, Xaq Pitkow, Fabian H Sinz, Andreas S Tolias

Faculty, Staff and Students Publications

The complexity of neural circuits makes it challenging to decipher the brain’s algorithms of intelligence. Recent breakthroughs in deep learning have produced models that accurately simulate brain activity, enhancing our understanding of the brain’s computational objectives and neural coding. However, it is difficult for such models to generalize beyond their training distribution, limiting their utility. The emergence of foundation models1 trained on vast datasets has introduced a new artificial intelligence paradigm with remarkable generalization capabilities. Here we collected large amounts of neural activity from visual cortices of multiple mice and trained a foundation model to accurately predict neuronal responses …

Alpha-Synuclein Phosphomimetic Y39e And S129d Knock-In Mice Show Cytosolic Alpha-Synuclein Localization Without Developing Neurodegeneration Or Motor Deficits, Youngdoo Kim, Bhupesh Vaidya, Joseph Mcinnes, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and nonmotor symptoms. Its pathological hallmarks include the accumulation of misfolded alpha-synuclein (α-Syn) in Lewy bodies and Lewy neurites. Phosphorylation of α-Syn is a prominent feature of these inclusions, but its role in disease pathogenesis remains unclear. To identify the role of α-Syn phosphorylation in synucleinopathy, we generated two Snca knock-in (KI) mouse models carrying phosphomimetic mutations at SncaY39 or SncaS129 (Snca^Y39E or Snca^S129D) which manipulated epitopes phosphorylated in the PD brain. Both Snca^Y39E and Snca^S129D KI mice displayed increased α-Syn phosphorylation, enhanced …

Distinct Patterns Of Pv And Sst Gabaergic Neuronal Activity In The Basal Forebrain During Olfactory-Guided Behavior In Mice, Elizabeth H Moss, Evelyne K Tantry, Elaine Le, Pey-Shyuan Chin, Priscilla Ambrosi, Katie L Brandel-Ankrapp, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Sensory perception relies on the flexible detection and interpretation of stimuli across variable contexts, conditions, and behavioral states. The basal forebrain (BF) is a hub for behavioral state regulation, supplying dense cholinergic and GABAergic projections to various brain regions involved in sensory processing. Of GABAergic neurons in the BF, parvalbumin (PV) and somatostatin (SST) subtypes serve opposing roles toward regulating behavioral states. To elucidate the role of BF circuits in sensory-guided behavior, we investigated GABAergic signaling dynamics during odor-guided decision-making in male and female mice. We used fiber photometry to record cell type-specific BF activity during an odor discrimination task …

Oxidized Carbon Nanoparticles Enhance Cellular Energetics With Application To Injured Brain, Karthik Mouli, Anton V Liopo, Emily A Mchugh, Erica Underwood, Jing Zhao, Pramod K Dash, Anh T T Vo, Vikas H Malojirao, Muralidhar L Hegde, James M Tour, Paul J Derry, Thomas A Kent

Faculty, Staff and Student Publications

Pro-energetic effects of functionalized, oxidized carbon nanozymes (OCNs) are reported. OCNs, derived from harsh acid oxidation of single-wall carbon nanotubes or activated charcoal are previously shown to possess multiple nanozymatic activities including mimicking superoxide dismutase and catalyzing the oxidation of reduced nicotinamide adenine dinucleotide (NADH) to NAD+. These actions are predicted to generate a glycolytic shift and enhance mitochondrial energetics under impaired conditions. Impaired mitochondrial energy metabolism is increasingly recognized as an important facet of traumatic brain injury (TBI) pathophysiology and decreases the efficiency of electron transport chain (ETC)-coupled adenosine triphosphate (ATP) and NAD+ regeneration. In vitro, OCNs promote a …