Neurosciences Commons^™

Social Behavioral Impairments In Syngap1-Related Intellectual Disability, Hajer Naveed, Maria Mccormack, J Lloyd Holder

Duncan NRI Faculty and Staff Publications

Introduction: Developmental synaptopathies are neurodevelopmental disorders caused by genetic mutations disrupting the development and function of neuronal synapses.

Methods: We administered the validated Social Responsiveness Scale, Second Edition (SRS-2) to investigate the phenotypic presentation of social-behavioral impairments for the developmental synaptopathy-SYNGAP1-related Intellectual Disability (SYNGAP1-ID) (n = 32) compared with a phenotypically similar disorder Phelan-McDermid syndrome (PMD) (n = 27) and healthy controls (n = 43). A short form SRS-2 analysis (n = 85) was also conducted.

Results: Both SYNGAP1-ID and PMD had significantly elevated total and subcategory T-scores, with no significant score differences between SYNGAP1 …

Upregulation Of The Escrt Pathway And Multivesicular Bodies Accelerates Degradation Of Proteins Associated With Neurodegeneration, Ron Benyair, Sai Srinivas Panapakkam Giridharan, Pilar Rivero-Ríos, Junya Hasegawa, Emily Bristow, Eeva-Liisa Eskelinen, Merav D Shmueli, Vered Fishbain-Yoskovitz, Yifat Merbl, Lisa M Sharkey, Henry L Paulson, Phyllis I Hanson, Samarjit Patnaik, Ismael Al-Ramahi, Juan Botas, Juan Marugan, Lois S Weisman

Duncan NRI Faculty and Staff Publications

Many neurodegenerative diseases, including Huntington’s disease (HD) and Alzheimer’s disease (AD), occur due to an accumulation of aggregation-prone proteins, which results in neuronal death. Studies in animal and cell models show that reducing the levels of these proteins mitigates disease phenotypes. We previously reported a small molecule, NCT-504, which reduces cellular levels of mutant huntingtin (mHTT) in patient fibroblasts as well as mouse striatal and cortical neurons from an HdhQ111 mutant mouse. Here, we show that NCT-504 has a broader potential, and in addition reduces levels of Tau, a protein associated with Alzheimer’s disease, as well as other tauopathies. We …

Function And Dysfunction Of The Dystonia Network: An Exploration Of Neural Circuits That Underlie The Acquired And Isolated Dystonias, Jason S Gill, Megan X Nguyen, Mariam Hull, Meike E Van Der Heijden, Ken Nguyen, Sruthi P Thomas, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Dystonia is a highly prevalent movement disorder that can manifest at any time across the lifespan. An increasing number of investigations have tied this disorder to dysfunction of a broad "dystonia network" encompassing the cerebellum, thalamus, basal ganglia, and cortex. However, pinpointing how dysfunction of the various anatomic components of the network produces the wide variety of dystonia presentations across etiologies remains a difficult problem. In this review, a discussion of functional network findings in non-mendelian etiologies of dystonia is undertaken. Initially acquired etiologies of dystonia and how lesion location leads to alterations in network function are explored, first through …

Xcvatr: Detection And Characterization Of Variant Impact On The Embeddings Of Single -Cell And Bulk Rna-Sequencing Samples, Arif Harmanci, Akdes Serin Harmanci, Tiemo J Klisch, Akash J Patel

Duncan NRI Faculty and Staff Publications

Background: RNA-sequencing has become a standard tool for analyzing gene activity in bulk samples and at the single-cell level. By increasing sample sizes and cell counts, this technique can uncover substantial information about cellular transcriptional states. Beyond quantification of gene expression, RNA-seq can be used for detecting variants, including single nucleotide polymorphisms, small insertions/deletions, and larger variants, such as copy number variants. Notably, joint analysis of variants with cellular transcriptional states may provide insights into the impact of mutations, especially for complex and heterogeneous samples. However, this analysis is often challenging due to a prohibitively high number of variants and …

Propranolol Modulates Cerebellar Circuit Activity And Reduces Tremor., Joy Zhou, Meike E Van Der Heijden, Luis E Salazar Leon, Tao Lin, Lauren N Miterko, Dominic J Kizek, Ross M Perez, Matea Pavešković, Amanda M Brown, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Tremor is the most common movement disorder. Several drugs reduce tremor severity, but no cures are available. Propranolol, a β-adrenergic receptor blocker, is the leading treatment for tremor. However, the in vivo circuit mechanisms by which propranolol decreases tremor remain unclear. Here, we test whether propranolol modulates activity in the cerebellum, a key node in the tremor network. We investigated the effects of propranolol in healthy control mice and Car8^wdl/wdl mice, which exhibit pathophysiological tremor and ataxia due to cerebellar dysfunction. Propranolol reduced physiological tremor in control mice and reduced pathophysiological tremor in Car8^wdl/wdl mice to control levels. …

Neurobehavioral Deficits And A Progressive Ictogenesis In The Tetrodotoxin Model Of Epileptic Spasms, John T Le, Carlos J Ballester-Rosado, James D Frost, John W Swann

Duncan NRI Faculty and Staff Publications

Objective: Our goal was to determine whether animals with a history of epileptic spasms have learning and memory deficits. We also used continuous (24/7) long-term electroencephalographic (EEG) recordings to evaluate the evolution of epileptiform activity in the same animals over time.

Methods: Object recognition memory and object location memory tests were undertaken, as well as a matching to place water maze test that evaluated working memory. A retrospective analysis was undertaken of long-term video/EEG recordings from rats with epileptic spasms. The frequency and duration of the ictal events of spasms were quantified.

Results: Rats with a history of epileptic spasms …

A Minimal Role For Synonymous Variation In Human Disease, Ryan S Dhindsa, Quanli Wang, Dimitrios Vitsios, Oliver S Burren, Fengyuan Hu, James E Dicarlo, Leonid Kruglyak, Daniel G Macarthur, Matthew E Hurles, Slavé Petrovski

Duncan NRI Faculty and Staff Publications

Synonymous mutations change the DNA sequence of a gene without affecting the amino acid sequence of the encoded protein. Although some synonymous mutations can affect RNA splicing, translational efficiency, and mRNA stability, studies in human genetics, mutagenesis screens, and other experiments and evolutionary analyses have repeatedly shown that most synonymous variants are neutral or only weakly deleterious, with some notable exceptions. Based on a recent study in yeast, there have been claims that synonymous mutations could be as important as nonsynonymous mutations in causing disease, assuming the yeast findings hold up and translate to humans. Here, we argue that there …

Development Of Myelinating Glia: An Overview, Carlo D Cristobal, Hyun Kyoung Lee

Duncan NRI Faculty and Staff Publications

Myelin is essential to nervous system function, playing roles in saltatory conduction and trophic support. Oligodendrocytes (OLs) and Schwann cells (SCs) form myelin in the central and peripheral nervous systems respectively and follow different developmental paths. OLs are neural stem-cell derived and follow an intrinsic developmental program resulting in a largely irreversible differentiation state. During embryonic development, OL precursor cells (OPCs) are produced in distinct waves originating from different locations in the central nervous system, with a subset developing into myelinating OLs. OPCs remain evenly distributed throughout life, providing a population of responsive, multifunctional cells with the capacity to remyelinate …

Notch Missense Mutations In Drosophila Reveal Functions Of Specific Egf-Like Repeats In Notch Folding, Trafficking, And Signaling, Hilman Nurmahdi, Mao Hasegawa, Elzava Yuslimatin Mujizah, Takeshi Sasamura, Mikiko Inaki, Shinya Yamamoto, Tomoko Yamakawa, Kenji Matsuno

Duncan NRI Faculty and Staff Publications

Notch signaling plays various roles in cell-fate specification through direct cell–cell interactions. Notch receptors are evolutionarily conserved transmembrane proteins with multiple epidermal growth factor (EGF)-like repeats. Drosophila Notch has 36 EGF-like repeats, and while some play a role in Notch signaling, the specific functions of most remain unclear. To investigate the role of each EGF-like repeat, we used 19 previously identified missense mutations of Notch with unique amino acid substitutions in various EGF-like repeats and a transmembrane domain; 17 of these were identified through a single genetic screen. We assessed these mutants’ phenotypes in the nervous system and hindgut during …

Influence Of Data Sampling Methods On The Representation Of Neural Spiking Activity In Vivo, Meike E Van Der Heijden, Amanda M Brown, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

No abstract provided.

Region-Specific Denoising Identifies Spatial Co-Expression Patterns And Intra-Tissue Heterogeneity In Spatially Resolved Transcriptomics Data, Linhua Wang, Mirjana Maletic-Savatic, Zhandong Liu

Duncan NRI Faculty and Staff Publications

Spatially resolved transcriptomics is a relatively new technique that maps transcriptional information within a tissue. Analysis of these datasets is challenging because gene expression values are highly sparse due to dropout events, and there is a lack of tools to facilitate in silico detection and annotation of regions based on their molecular content. Therefore, we develop a computational tool for detecting molecular regions and region-based Missing value Imputation for Spatially Transcriptomics (MIST). We validate MIST-identified regions across multiple datasets produced by 10x Visium Spatial Transcriptomics, using manually annotated histological images as references. We benchmark MIST against a spatial k-nearest neighboring …

Two Neuronal Peptides Encoded From A Single Transcript Regulate Mitochondrial Complex Iii In Drosophila, Justin A Bosch, Berrak Ugur, Israel Pichardo-Casas, Jordan Rabasco, Felipe Escobedo, Zhongyuan Zuo, Ben Brown, Susan Celniker, David A Sinclair, Hugo J Bellen, Norbert Perrimon

Duncan NRI Faculty and Staff Publications

Naturally produced peptides (<100 amino acids) are important regulators of physiology, development, and metabolism. Recent studies have predicted that thousands of peptides may be translated from transcripts containing small open-reading frames (smORFs). Here, we describe two peptides in Drosophila encoded by conserved smORFs, Sloth1 and Sloth2. These peptides are translated from the same bicistronic transcript and share sequence similarities, suggesting that they encode paralogs. Yet, Sloth1 and Sloth2 are not functionally redundant, and loss of either peptide causes animal lethality, reduced neuronal function, impaired mitochondrial function, and neurodegeneration. We provide evidence that Sloth1/2 are highly expressed in neurons, imported to mitochondria, and regulate mitochondrial complex III assembly. These results suggest that phenotypic analysis of smORF genes in Drosophila can provide a wealth of information on the biological functions of this poorly characterized class of …

Oxytocin Signaling Is Necessary For Synaptic Maturation Of Adult-Born Neurons, Brandon T Pekarek, Mikhail Kochukov, Brittney Lozzi, Timothy Wu, Patrick J Hunt, Burak Tepe, Elizabeth Hanson Moss, Evelyne K Tantry, Jessica L Swanson, Sean W Dooling, Mayuri Patel, Benjamin D W Belfort, Juan M Romero, Suyang Bao, Matthew C Hill, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Neural circuit plasticity and sensory response dynamics depend on forming new synaptic connections. Despite recent advances toward understanding the consequences of circuit plasticity, the mechanisms driving circuit plasticity are unknown. Adult-born neurons within the olfactory bulb have proven to be a powerful model for studying circuit plasticity, providing a broad and accessible avenue into neuron development, migration, and circuit integration. We and others have shown that efficient adult-born neuron circuit integration hinges on presynaptic activity in the form of diverse signaling peptides. Here, we demonstrate a novel oxytocin-dependent mechanism of adult-born neuron synaptic maturation and circuit integration. We reveal spatial …

Distinct Organization Of Two Cortico-Cortical Feedback Pathways, Shan Shen, Xiaolong Jiang, Federico Scala, Jiakun Fu, Paul Fahey, Dmitry Kobak, Zhenghuan Tan, Na Zhou, Jacob Reimer, Fabian Sinz, Andreas S Tolias

Duncan NRI Faculty and Staff Publications

Neocortical feedback is critical for attention, prediction, and learning. To mechanically understand its function requires deciphering its cell-type wiring. Recent studies revealed that feedback between primary motor to primary somatosensory areas in mice is disinhibitory, targeting vasoactive intestinal peptide-expressing interneurons, in addition to pyramidal cells. It is unknown whether this circuit motif represents a general cortico-cortical feedback organizing principle. Here we show that in contrast to this wiring rule, feedback between higher-order lateromedial visual area to primary visual cortex preferentially activates somatostatin-expressing interneurons. Functionally, both feedback circuits temporally sharpen feed-forward excitation eliciting a transient increase–followed by a prolonged decrease–in pyramidal …

Cluster Analysis Of Short Sensory Profile Data Reveals Sensory-Based Subgroups In Autism Spectrum Disorder, Ariel M Lyons-Warren, Michael F Wangler, Ying-Wooi Wan

Duncan NRI Faculty and Staff Publications

Autism spectrum disorder is a common, heterogeneous neurodevelopmental disorder lacking targeted treatments. Additional features include restricted, repetitive patterns of behaviors and differences in sensory processing. We hypothesized that detailed sensory features including modality specific hyper- and hypo-sensitivity could be used to identify clinically recognizable subgroups with unique underlying gene variants. Participants included 378 individuals with a clinical diagnosis of autism spectrum disorder who contributed Short Sensory Profile data assessing the frequency of sensory behaviors and whole genome sequencing results to the Autism Speaks’ MSSNG database. Sensory phenotypes in this cohort were not randomly distributed with 10 patterns describing 43% (162/378) …

De Novo Variants In Frmd5 Are Associated With Developmental Delay, Intellectual Disability, Ataxia, And Abnormalities Of Eye Movement, Shenzhao Lu, Mengqi Ma, Xiao Mao, Carlos A Bacino, Joseph Jankovic, V Reid Sutton, James A Bartley, Xueying Wang, Jill A Rosenfeld, Ana Beleza-Meireles, Jaynee Chauhan, Xueyang Pan, Megan Li, Pengfei Liu, Katrina Prescott, Sam Amin, George Davies, Michael F Wangler, Yuwei Dai, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

Proteins containing the FERM (four-point-one, ezrin, radixin, and moesin) domain link the plasma membrane with cytoskeletal structures at specific cellular locations and have been implicated in the localization of cell-membrane-associated proteins and/or phosphoinositides. FERM domain-containing protein 5 (FRMD5) localizes at cell adherens junctions and stabilizes cell-cell contacts. To date, variants in FRMD5 have not been associated with a Mendelian disease in OMIM. Here, we describe eight probands with rare heterozygous missense variants in FRMD5 who present with developmental delay, intellectual disability, ataxia, seizures, and abnormalities of eye movement. The variants are de novo in all for whom parental testing was …

The Recurrent De Novo C.2011c>T Missense Variant In Mtss2 Causes Syndromic Intellectual Disability, Yan Huang, Gabrielle Lemire, Lauren C Briere, Fang Liu, Marja W Wessels, Xueqi Wang, Matthew Osmond, Oguz Kanca, Shenzhao Lu, Frances A High, Melissa A Walker, Lance H Rodan, Undiagnosed Diseases Network, Care4rare Canada Consortium, Kristin D Kernohan, David A Sweetser, Kym M Boycott, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

MTSS2, also known as MTSS1L, binds to plasma membranes and modulates their bending. MTSS2 is highly expressed in the central nervous system (CNS) and appears to be involved in activity-dependent synaptic plasticity. Variants in MTSS2 have not yet been associated with a human phenotype in OMIM. Here we report five individuals with the same heterozygous de novo variant in MTSS2 (GenBank: NM_138383.2: c.2011C>T [p.Arg671Trp]) identified by exome sequencing. The individuals present with global developmental delay, mild intellectual disability, ophthalmological anomalies, microcephaly or relative microcephaly, and shared mild facial dysmorphisms. Immunoblots of fibroblasts from two affected individuals revealed that the …

Causal Evidence For A Role Of Cerebellar Lobulus Simplex In Prefrontal-Hippocampal Interaction In Spatial Working Memory Decision-Making, Yu Liu, Samuel S Mcafee, Meike E Van Der Heijden, Mukesh Dhamala, Roy V Sillitoe, Detlef H Heck

Duncan NRI Faculty and Staff Publications

Spatial working memory (SWM) is a cerebrocerebellar cognitive skill supporting survival-relevant behaviors, such as optimizing foraging behavior by remembering recent routes and visited sites. It is known that SWM decision-making in rodents requires the medial prefrontal cortex (mPFC) and dorsal hippocampus. The decision process in SWM tasks carries a specific electrophysiological signature of a brief, decision-related increase in neuronal communication in the form of an increase in the coherence of neuronal theta oscillations (4-12 Hz) between the mPFC and dorsal hippocampus, a finding we replicated here during spontaneous exploration of a plus maze in freely moving mice. We further evaluated …

Identifying Phenotypic Expansions For Congenital Diaphragmatic Hernia Plus (Cdh+) Using Decipher Data, Amy Hardcastle, Aliska M Berry, Ian M Campbell, Xiaonan Zhao, Pengfei Liu, Amanda E Gerard, Jill A Rosenfeld, Saumya D Sisoudiya, Andres Hernandez-Garcia, Sara Loddo, Silvia Di Tommaso, Antonio Novelli, Maria L Dentici, Rossella Capolino, Maria C Digilio, Ludovico Graziani, Cecilie F Rustad, Katherine Neas, Giovanni B Ferrero, Alfredo Brusco, Eleonora Di Gregorio, Diana Wellesley, Claire Beneteau, Madeleine Joubert, Kris Van Den Bogaert, Anneleen Boogaerts, Dominic J Mcmullan, John Dean, Maria G Giuffrida, Laura Bernardini, Vinod Varghese, Nora L Shannon, Rachel E Harrison, Wayne W K Lam, Shane Mckee, Peter D Turnpenny, Trevor Cole, Jenny Morton, Jacqueline Eason, Marilyn C Jones, Rebecca Hall, Michael Wright, Karen Horridge, Chad A Shaw, Wendy K Chung, Daryl A Scott

Duncan NRI Faculty and Staff Publications

Congenital diaphragmatic hernia (CDH) can occur in isolation or in conjunction with other birth defects (CDH+). A molecular etiology can only be identified in a subset of CDH cases. This is due, in part, to an incomplete understanding of the genes that contribute to diaphragm development. Here, we used clinical and molecular data from 36 individuals with CDH+ who are cataloged in the DECIPHER database to identify genes that may play a role in diaphragm development and to discover new phenotypic expansions. Among this group, we identified individuals who carried putatively deleterious sequence or copy number variants affecting CREBBP, SMARCA4, …

Potential Interactions Between Cerebellar Dysfunction And Sleep Disturbances In Dystonia, Luis E Salazar Leon, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Dystonia is the third most common movement disorder. It causes debilitating twisting postures that are accompanied by repetitive and sometimes intermittent co- or over-contractions of agonist and antagonist muscles. Historically diagnosed as a basal ganglia disorder, dystonia is increasingly considered a network disorder involving various brain regions including the cerebellum. In certain etiologies of dystonia, aberrant motor activity is generated in the cerebellum and the abnormal signals then propagate through a "dystonia circuit" that includes the thalamus, basal ganglia, and cerebral cortex. Importantly, it has been reported that non-motor defects can accompany the motor symptoms; while their severity is not …

Sex-Specific Epigenetic Development In The Mouse Hypothalamic Arcuate Nucleus Pinpoints Human Genomic Regions Associated With Body Mass Index, Harry Mackay, Chathura J Gunasekara, Kit-Yi Yam, Dollada Srisai, Hari Krishna Yalamanchili, Yumei Li, Rui Chen, Cristian Coarfa, Robert A Waterland

Duncan NRI Faculty and Staff Publications

Recent genome-wide association studies corroborate classical research on developmental programming indicating that obesity is primarily a neurodevelopmental disease strongly influenced by nutrition during critical ontogenic windows. Epigenetic mechanisms regulate neurodevelopment; however, little is known about their role in establishing and maintaining the brain's energy balance circuitry. We generated neuron and glia methylomes and transcriptomes from male and female mouse hypothalamic arcuate nucleus, a key site for energy balance regulation, at time points spanning the closure of an established critical window for developmental programming of obesity risk. We find that postnatal epigenetic maturation is markedly cell type and sex specific and …

De Novo Variants In Emc1 Lead To Neurodevelopmental Delay And Cerebellar Degeneration And Affect Glial Function In Drosophila, Hyung-Lok Chung, Patrick Rump, Di Lu, Megan R Glassford, Jung-Wan Mok, Jawid Fatih, Adily Basal, Paul C Marcogliese, Oguz Kanca, Michele Rapp, Johanna M Fock, Erik-Jan Kamsteeg, James R Lupski, Austin Larson, Mark C Haninbal, Hugo Bellen, Tamar Harel

Duncan NRI Faculty and Staff Publications

Background: The endoplasmic reticulum (ER)-membrane protein complex (EMC) is a multi-protein transmembrane complex composed of 10 subunits that functions as a membrane-protein chaperone. Variants in EMC1 lead to neurodevelopmental delay and cerebellar degeneration. Multiple families with biallelic variants have been published, yet to date, only a single report of a monoallelic variant has been described, and functional evidence is sparse.

Methods: Exome sequencing was used to investigate the genetic cause underlying severe developmental delay in three unrelated children. EMC1 variants were modeled in Drosophila, using loss-of-function (LoF) and overexpression studies. Glial-specific and neuronal-specific assays were used to determine whether the …

Identification Of Risk Genes For Alzheimer’S Disease By Gene Embedding, Yashwanth Lagisetty, Thomas Bourquard, Ismael Al-Ramahi, Carl Grant Mangleburg, Samantha Mota, Shirin Soleimani, Joshua M Shulman, Juan Botas, Kwanghyuk Lee, Olivier Lichtarge

Duncan NRI Faculty and Staff Publications

Most disease-gene association methods do not account for gene-gene interactions, even though these play a crucial role in complex, polygenic diseases like Alzheimer’s disease (AD). To discover new genes whose interactions may contribute to pathology, we introduce GeneEMBED. This approach compares the functional perturbations induced in gene interaction network neighborhoods by coding variants from disease versus healthy subjects. In two independent AD cohorts of 5,169 exomes and 969 genomes, GeneEMBED identified novel candidates. These genes were differentially expressed in post mortem AD brains and modulated neurological phenotypes in mice. Four that were differentially overexpressed and modified neurodegeneration in vivo are …

Why Study Mechanisms Of Brain Stimulation Therapies? To Modulate The Right Neurons, In The Right Way, At The Right Time, Matthew J Mcginley, Steven T Lee

Duncan NRI Faculty and Staff Publications

Clinical applications of vagus nerve stimulation (VNS) are burgeoning, but mechanistic work lags behind. In this issue of Neuron, Bowles and colleagues show that VNS timed with positive reinforcement improves motor learning and cortical function by a cholinergic mechanism.

The Tfeb-Tgif1 Axis Regulates Emt In Mouse Epicardial Cells, Elena Astanina, Gabriella Doronzo, Davide Corà, Francesco Neri, Salvatore Oliviero, Tullio Genova, Federico Mussano, Emanuele Middonti, Edoardo Vallariello, Chiara Cencioni, Donatella Valdembri, Guido Serini, Federica Limana, Eleonora Foglio, Andrea Ballabio, Federico Bussolino

Duncan NRI Faculty and Staff Publications

Epithelial-mesenchymal transition (EMT) is a complex and pivotal process involved in organogenesis and is related to several pathological processes, including cancer and fibrosis. During heart development, EMT mediates the conversion of epicardial cells into vascular smooth muscle cells and cardiac interstitial fibroblasts. Here, we show that the oncogenic transcription factor EB (TFEB) is a key regulator of EMT in epicardial cells and that its genetic overexpression in mouse epicardium is lethal due to heart defects linked to impaired EMT. TFEB specifically orchestrates the EMT-promoting function of transforming growth factor (TGF) β, and this effect results from activated transcription of thymine-guanine-interacting …

Kctd7 Deficiency Induces Myoclonic Seizures Associated With Purkinje Cell Death And Microvascular Defects, Justine H Liang, Jonathan Alevy, Viktor Akhanov, Ryan Seo, Cory A Massey, Danye Jiang, Joy Zhou, Roy V Sillitoe, Jeffrey L Noebels, Melanie A Samuel

Duncan NRI Faculty and Staff Publications

Mutations in the potassium channel tetramerization domain-containing 7 (KCTD7) gene are associated with a severe neurodegenerative phenotype characterized by childhood onset of progressive and intractable myoclonic seizures accompanied by developmental regression. KCTD7-driven disease is part of a large family of progressive myoclonic epilepsy syndromes displaying a broad spectrum of clinical severity. Animal models of KCTD7-related disease are lacking, and little is known regarding how KCTD7 protein defects lead to epilepsy and cognitive dysfunction. We characterized Kctd7 expression patterns in the mouse brain during development and show that it is selectively enriched in specific regions as the brain matures. We further …

Evidence For An Association Between Coffin-Siris Syndrome And Congenital Diaphragmatic Hernia, Yoel Gofin, Xiaonan Zhao, Amanda Gerard, Fernando Scaglia, Michael F Wangler, Samantha A Schrier Vergano, Daryl A Scott

Duncan NRI Faculty and Staff Publications

Coffin-Siris syndrome (CSS) is an autosomal dominant neurodevelopmental syndrome that can present with a variety of structural birth defects. Pathogenic variants in 12 genes have been shown to cause CSS. Most of these genes encode proteins that are a part of the mammalian switch/sucrose non-fermentable (mSWI/SNF; BAF) complex. An association between genes that cause CSS and congenital diaphragmatic hernia (CDH) has been suggested based on case reports and the analysis of CSS and CDH cohorts. Here, we describe an unpublished individual with CSS and CDH, and we report additional clinical information on four published cases. Data from these individuals, and …

‘Fly-Ing’ From Rare To Common Neurodegenerative Disease Mechanisms, Mengqi Ma, Matthew J Moulton, Shenzhao Lu, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

Genome sequencing advances have enabled researchers and clinicians to probe vast numbers of human variants to distinguish pathogenic from benign variation. Model organisms have been critical in variant assessment and delineating molecular mechanisms of some of the diseases caused by these variants. The fruit fly, Drosophila melanogaster, has played a valuable role in this endeavor, taking advantage of its genetic technologies and established biological knowledge. In this review, we highlight the utility of the fly in studying the function of genes associated with rare neurological diseases that have led to a better understanding of common disease mechanisms. We emphasize …

Removal Of Kcnq2 From Parvalbumin-Expressing Interneurons Improves Anti-Seizure Efficacy Of Retigabine, Junzhan Jing, Corrinne Dunbar, Alina Sonesra, Ana Chavez, Suhyeorn Park, Ryan Yang, Heun Soh, Maxwell Lee, Anastasios V Tzingounis, Edward C Cooper, Xiaolong Jiang, Atul Maheshwari

Duncan NRI Faculty and Staff Publications

Anti-seizure drug (ASD) targets are widely expressed in both excitatory and inhibitory neurons. It remains unknown if the action of an ASD upon inhibitory neurons could counteract its beneficial effects on excitatory neurons (or vice versa), thereby reducing the efficacy of the ASD. Here, we examine whether the efficacy of the ASD retigabine (RTG) is altered after removal of the Kv7 potassium channel subunit KCNQ2, one of its drug targets, from parvalbumin-expressing interneurons (PV-INs). Parvalbumin-Cre (PV-Cre) mice were crossed with Kcnq2-floxed (Kcnq2fl/fl) mice to conditionally delete Kcnq2 from PV-INs. In these conditional knockout mice (cKO, PV-Kcnq2 …

Cancer-Driving Mutations Are Enriched In Genic Regions Intolerant To Germline Variation, Dimitrios Vitsios, Ryan S Dhindsa, Dorota Matelska, Jonathan Mitchell, Xuequing Zou, Joshua Armenia, Fengyuan Hu, Quanli Wang, Ben Sidders, Andrew R Harper, Slavé Petrovski

Duncan NRI Faculty and Staff Publications

Large reference datasets of protein-coding variation in human populations have allowed us to determine which genes and genic subregions are intolerant to germline genetic variation. There is also a growing number of genes implicated in severe Mendelian diseases that overlap with genes implicated in cancer. We hypothesized that cancer-driving mutations might be enriched in genic subregions that are depleted of germline variation relative to somatic variation. We introduce a new metric, OncMTR (oncology missense tolerance ratio), which uses 125,748 exomes in the Genome Aggregation Database (gnomAD) to identify these genic subregions. We demonstrate that OncMTR can significantly predict driver mutations …