Medicine and Health Sciences Commons^™

A Novel Sting1 Variant Causes A Recessive Form Of Sting-Associated Vasculopathy With Onset In Infancy (Savi)., Bin Lin, Roberta Berard, Abdulrahman Al Rasheed, Buthaina Aladba, Philip J Kranzusch, Maggie Henderlight, Alexi Grom, Dana Kahle, Sofia Torreggiani, Alexander G Aue, Jacob Mitchell, Adriana A De Jesus, Grant S Schulert, Raphaela Goldbach-Mansky

Paediatrics Publications

No abstract provided.

Transient Hyponatremia Of Prematurity Caused By Mild Bartter Syndrome Type Ii: A Case Report., Subhrata Verma, Rahul Chanchlani, Victoria Mok Siu, Guido Filler

Paediatrics Publications

BACKGROUND: Bartter syndrome subtypes are a group of rare renal tubular diseases characterized by impaired salt reabsorption in the tubule, specifically the thick ascending limb of Henle's loop. Clinically, they are characterized by the association of hypokalemic metabolic alkalosis, hypercalciuria, nephrocalcinosis, increased levels of plasma renin and aldosterone, low blood pressure and vascular resistance to angiotensin II. Bartter syndrome type II is caused by mutations in the renal outer medullary potassium channel (ROMK) gene (KCNJ1), can present in the newborn period and typically requires lifelong therapy.

CASE PRESENTATION: We describe a case of a prematurely born female infant presenting with …

Effects Of A Postnatal Atrx Conditional Knockout In Neurons On Autism-Like Behaviours In Male And Female Mice., Nicole Martin-Kenny, Nathalie G Bérubé

Paediatrics Publications

BACKGROUND: Alpha-thalassemia/mental retardation, X-linked, or ATRX, is an autism susceptibility gene that encodes a chromatin remodeler. Mutations of ATRX result in the ATR-X intellectual disability syndrome and have been identified in autism spectrum disorder (ASD) patients. The mechanisms by which ATRX mutations lead to autism and autistic-like behaviours are not yet known. To address this question, we generated mice with postnatal Atrx inactivation in excitatory neurons of the forebrain and performed a battery of behavioural assays that assess autistic-like behaviours.

METHODS: Male and female mice with a postnatal conditional ablation of ATRX were generated using the Cre/lox system under the …

Growth Hormone Deficiency In Megalencephaly-Capillary Malformation Syndrome: An Association With Activating Mutations In Pik3ca, Shanlee Davis, Meredith A Ware, Jordan Zeiger, Matthew A Deardorff, Katheryn Grand, Adda Grimberg, Stephanie Hsu, Megan Kelsey, Shideh Majidi, Revi P Matthew, Melanie Napier, Natalie Nokoff, Chitra Prasad, Andrew C Riggs, Margaret L Mckinnon, Ghayda Mirzaa

Paediatrics Publications

Megalencephaly-capillary malformation syndrome (MCAP) is a brain overgrowth disorder characterized by cortical malformations (specifically polymicrogyria), vascular anomalies, and segmental overgrowth secondary to somatic activating mutations in the PI3K-AKT-MTOR pathway (PIK3CA). Cases of growth failure and hypoglycemia have been reported in patients with MCAP, raising the suspicion for unappreciated growth hormone (GH) deficiency. Here we report an observational multicenter study of children with MCAP and GH deficiency. Eleven participants were confirmed to have GH deficiency, all with very low or undetectable circulating concentrations of insulin-like growth factor-1 and insulin-like growth factor binding protein-3. Seven underwent GH stimulation testing and all had …

Bafopathies' Dna Methylation Epi-Signatures Demonstrate Diagnostic Utility And Functional Continuum Of Coffin-Siris And Nicolaides-Baraitser Syndromes., Erfan Aref-Eshghi, Eric G Bend, Rebecca L Hood, Laila C Schenkel, Deanna Alexis Carere, Rana Chakrabarti, Sandesh C S Nagamani, Sau Wai Cheung, Philippe M Campeau, Chitra Prasad, Victoria Mok Siu, Lauren Brady, Mark A Tarnopolsky, David J Callen, A Micheil Innes, Susan M White, Wendy S Meschino, Andrew Y Shuen, Guillaume Paré, Dennis E Bulman, Peter J Ainsworth, Hanxin Lin, David I Rodenhiser, Raoul C Hennekam, Kym M Boycott, Charles E Schwartz, Bekim Sadikovic

Paediatrics Publications

Coffin-Siris and Nicolaides-Baraitser syndromes (CSS and NCBRS) are Mendelian disorders caused by mutations in subunits of the BAF chromatin remodeling complex. We report overlapping peripheral blood DNA methylation epi-signatures in individuals with various subtypes of CSS (ARID1B, SMARCB1, and SMARCA4) and NCBRS (SMARCA2). We demonstrate that the degree of similarity in the epi-signatures of some CSS subtypes and NCBRS can be greater than that within CSS, indicating a link in the functional basis of the two syndromes. We show that chromosome 6q25 microdeletion syndrome, harboring ARID1B deletions, exhibits a similar CSS/NCBRS methylation profile. Specificity of this epi-signature was confirmed across …

App21 Transgenic Rats Develop Age-Dependent Cognitive Impairment And Microglia Accumulation Within White Matter Tracts., Nina Weishaupt, Qingfan Liu, Sheojung Shin, Ramandeep Singh, Yuksel Agca, Cansu Agca, Vladimir Hachinski, Shawn Narain Whitehead

Paediatrics Publications

Background

Most of the animal models commonly used for preclinical research into Alzheimer's disease (AD) largely fail to address the pathophysiology, including the impact of known risk factors, of the widely diagnosed sporadic form of the disease. Here, we use a transgenic rat (APP21) that does not develop AD-like pathology spontaneously with age, but does develop pathology following vascular stress. To further the potential of this novel rat model as a much-needed pre-clinical animal model of sporadic AD, we characterize APP21 transgenic rats behaviorally and histologically up to 19 months of age.

Methods

The open field test was used as …

N-Glycosylation Regulates Pannexin 2 Localization But Is Not Required For Interacting With Pannexin 1., Rafael E Sanchez-Pupo, Danielle Johnston, Silvia Penuela

Anatomy and Cell Biology Publications

Pannexins (Panx1, 2, 3) are channel-forming glycoproteins expressed in mammalian tissues. We previously reported that N-glycosylation acts as a regulator of the localization and intermixing of Panx1 and Panx3, but its effects on Panx2 are currently unknown. Panx1 and Panx2 intermixing can regulate channel properties, and both pannexins have been implicated in neuronal cell death after ischemia. Our objectives were to validate the predicted N-glycosylation site of Panx2 and to study the effects of Panx2 glycosylation on localization and its capacity to interact with Panx1. We used site-directed mutagenesis, enzymatic de-glycosylation, cell-surface biotinylation, co-immunoprecipitation, and confocal microscopy. Our results showed …

Comparative Analysis Of Mutant Huntingtin Binding Partners In Yeast Species., Yanding Zhao, Ashley A Zurawel, Nicole P Jenkins, Martin L Duennwald, Chao Cheng, Arminja N Kettenbach, Surachai Supattapone

Anatomy and Cell Biology Publications

Huntington's disease is caused by the pathological expansion of a polyglutamine (polyQ) stretch in Huntingtin (Htt), but the molecular mechanisms by which polyQ expansion in Htt causes toxicity in selective neuronal populations remain poorly understood. Interestingly, heterologous expression of expanded polyQ Htt is toxic in Saccharomyces cerevisiae cells, but has no effect in Schizosaccharomyces pombe, a related yeast species possessing very few endogenous polyQ or Q/N-rich proteins. Here, we used a comprehensive and unbiased mass spectrometric approach to identify proteins that bind Htt in a length-dependent manner in both species. Analysis of the expanded polyQ-associated proteins reveals marked enrichment of …

Computational Modelling Of Human Transcriptional Regulation By An Information Theory-Based Approach, Ruipeng Lu

Electronic Thesis and Dissertation Repository

ChIP-seq experiments can identify the genome-wide binding site motifs of a transcription factor (TF) and determine its sequence specificity. Multiple algorithms were developed to derive TF binding site (TFBS) motifs from ChIP-seq data, including the entropy minimization-based Bipad that can derive both contiguous and bipartite motifs. Prior studies applying these algorithms to ChIP-seq data only analyzed a small number of top peaks with the highest signal strengths, biasing their resultant position weight matrices (PWMs) towards consensus-like, strong binding sites; nor did they derive bipartite motifs, disabling the accurate modelling of binding behavior of dimeric TFs.

This thesis presents a novel …

Peripheral Blood Epi-Signature Of Claes-Jensen Syndrome Enables Sensitive And Specific Identification Of Patients And Healthy Carriers With Pathogenic Mutations In Kdm5c, Laila C Schenkel, Erfan Aref-Eshghi, Cindy Skinner, Peter Ainsworth, Hanxin Lin, Guillaume Paré, David I Rodenhiser, Charles Schwartz, Bekim Sadikovic

Paediatrics Publications

Background

Claes-Jensen syndrome is an X-linked inherited intellectual disability caused by mutations in the

Results

Genome-wide DNA methylation analysis of 7 male patients affected with Claes-Jensen syndrome and 56 age- and sex-matched controls identified a specific DNA methylation defect (epi-signature) in the peripheral blood of these patients, including 1769 individual CpGs and 9 genomic regions. Six healthy female carriers showed less pronounced but distinctive changes in the same regions enabling their differentiation from both patients and controls. Highly specific computational model using the most significant methylation changes demonstrated 100% accuracy in differentiating patients, carriers, and controls in the training cohort, …

Mutations In Keops-Complex Genes Cause Nephrotic Syndrome With Primary Microcephaly, Daniela A Braun, Jia Rao, Geraldine Mollet, David Schapiro, Marie-Claire Daugeron, Weizhen Tan, Olivier Gribouval, Olivia Boyer, Patrick Revy, Tilman Jobst-Schwan, Johanna Magdalena Schmidt, Jennifer A Lawson, Denny Schanze, Shazia Ashraf, Jeremy F P Ullmann, Charlotte A Hoogstraten, Nathalie Boddaert, Bruno Collinet, Gaëlle Martin, Dominique Liger, Svjetlana Lovric, Monica Furlano, I Chiara Guerrera, Oraly Sanchez-Ferras, Jennifer F Hu, Anne-Claire Boschat, Sylvia Sanquer, Björn Menten, Sarah Vergult, Nina De Rocker, Merlin Airik, Tobias Hermle, Shirlee Shril, Eugen Widmeier, Heon Yung Gee, Won-Il Choi, Carolin E Sadowski, Werner L Pabst, Jillian K Warejko, Ankana Daga, Tamara Basta, Verena Matejas, Karin Scharmann, Sandra D Kienast, Babak Behnam, Brendan Beeson, Amber Begtrup, Malcolm Bruce, Gaik-Siew Ch'ng, Shuan-Pei Lin, Jui-Hsing Chang, Chao-Huei Chen, Megan T Cho, Patrick M Gaffney, Patrick E Gipson, Chyong-Hsin Hsu, Jameela A Kari, Yu-Yuan Ke, Cathy Kiraly-Borri, Wai-Ming Lai, Emmanuelle Lemyre, Rebecca Okashah Littlejohn, Amira Masri, Mastaneh Moghtaderi, Kazuyuki Nakamura, Fatih Ozaltin, Marleen Praet, Chitra Prasad, Agnieszka Prytula, Elizabeth R Roeder, Patrick Rump, Rhonda E Schnur, Takashi Shiihara, Manish D Sinha, Neveen A Soliman, Kenza Soulami, David A Sweetser, Wen-Hui Tsai, Jeng-Daw Tsai, Rezan Topaloglu, Udo Vester, David H Viskochil, Nithiwat Vatanavicharn, Jessica L Waxler, Klaas J Wierenga, Matthias T F Wolf, Sik-Nin Wong, Sebastian A Leidel, Gessica Truglio, Peter C Dedon, Annapurna Poduri, Shrikant Mane, Richard P Lifton, Maxime Bouchard, Peter Kannu, David Chitayat, Daniella Magen, Bert Callewaert, Herman Van Tilbeurgh, Martin Zenker, Corinne Antignac, Friedhelm Hildebrandt

Paediatrics Publications

Galloway-Mowat syndrome (GAMOS) is an autosomal-recessive disease characterized by the combination of early-onset nephrotic syndrome (SRNS) and microcephaly with brain anomalies. Here we identified recessive mutations in OSGEP, TP53RK, TPRKB, and LAGE3, genes encoding the four subunits of the KEOPS complex, in 37 individuals from 32 families with GAMOS. CRISPR-Cas9 knockout in zebrafish and mice recapitulated the human phenotype of primary microcephaly and resulted in early lethality. Knockdown of OSGEP, TP53RK, or TPRKB inhibited cell proliferation, which human mutations did not rescue. Furthermore, knockdown of these genes impaired protein translation, caused endoplasmic reticulum stress, activated DNA-damage-response signaling, and ultimately induced …

Therapeutic And Prognostic Implications Of Braf V600e In Pediatric Low-Grade Gliomas., Alvaro Lassaletta, Michal Zapotocky, Matthew Mistry, Vijay Ramaswamy, Marion Honnorat, Rahul Krishnatry, Ana Guerreiro Stucklin, Nataliya Zhukova, Anthony Arnoldo, Scott Ryall, Catriona Ling, Tara Mckeown, Jim Loukides, Ofelia Cruz, Carmen De Torres, Cheng-Ying Ho, Roger J Packer, Ruth Tatevossian, Ibrahim Qaddoumi, Julie H Harreld, James D Dalton, Jean Mulcahy-Levy, Nicholas Foreman, Matthias A Karajannis, Shiyang Wang, Matija Snuderl, Amulya Nageswara Rao, Caterina Giannini, Mark Kieran, Keith L Ligon, Maria Luisa Garre, Paolo Nozza, Samantha Mascelli, Alessandro Raso, Sabine Mueller, Theodore Nicolaides, Karen Silva, Romain Perbet, Alexandre Vasiljevic, Cécile Faure Conter, Didier Frappaz, Sarah Leary, Courtney Crane, Aden Chan, Ho-Keung Ng, Zhi-Feng Shi, Ying Mao, Elizabeth Finch, David Eisenstat, Bev Wilson, Anne Sophie Carret, Peter Hauser, David Sumerauer, Lenka Krskova, Valerie Larouche, Adam Fleming, Shayna Zelcer, Nada Jabado, James T Rutka, Peter Dirks, Michael D Taylor, Shiyi Chen, Ute Bartels, Annie Huang, David W Ellison, Eric Bouffet, Cynthia Hawkins, Uri Tabori

Paediatrics Publications

Purpose BRAF V600E is a potentially highly targetable mutation detected in a subset of pediatric low-grade gliomas (PLGGs). Its biologic and clinical effect within this diverse group of tumors remains unknown.

Patients and Methods A combined clinical and genetic institutional study of patients with PLGGs with long-term follow-up was performed (N = 510). Clinical and treatment data of patients with BRAF V600E mutated PLGG (n = 99) were compared with a large international independent cohort of patients with BRAF V600E mutated-PLGG (n = 180).

Results BRAF V600E mutation was detected in 69 of 405 patients (17%) with PLGG across a …

Prolonged In Vivo Retention Of A Cathepsin D Targeted Optical Contrast Agent In A Mouse Model Of Alzheimer's Disease., Jonatan A Snir, Mojmir Suchy, Keith St Lawrence, Robert H E Hudson, Stephen H Pasternak, Robert Bartha

Brain and Mind Institute Researchers' Publications

BACKGROUND: Cathepsin D (CatD) is a lysosomal protease that is elevated early in Alzheimer's disease (AD). We have previously developed a Targeted contrast agent (CA) to detect CatD activity in vivo, consisting of a magnetic resonance imaging/fluorescent moiety linked to a cell penetrating peptide (CPP) by means of a CatD cleavage site and have demonstrated its uptake in the brain of an AD mouse model.

OBJECTIVE: The purpose of this study was to characterize the in vivo retention of a near infra-red fluorescent dye labeled version of this CA.

METHODS: Six adult C57Bl/6 wild-type mice and six adult 5XFAD transgenic …

Exploiting High-Throughput Cell Line Drug Screening Studies To Identify Candidate Therapeutic Agents In Head And Neck Cancer, Anthony C Nichols, Morgan Black, John Yoo, Nicole Pinto, Andrew Fernandes, Benjamin Haibe-Kains, Paul C Boutros, John W Barrett

Oncology Publications

BACKGROUND: There is an urgent need for better therapeutics in head and neck squamous cell cancer (HNSCC) to improve survival and decrease treatment morbidity. Recent advances in high-throughput drug screening techniques and next-generation sequencing have identified new therapeutic targets in other cancer types, but an HNSCC-specific study has not yet been carried out. We have exploited data from two large-scale cell line projects to clearly describe the mutational and copy number status of HNSCC cell lines and identify candidate drugs with elevated efficacy in HNSCC.

METHODS: The genetic landscape of 42 HNSCC cell lines including mutational and copy number data …

Skin Disease And Non-Syndromic Hearing Loss-Linked Cx30 Mutations Exhibit Several Distinct Cellular Pathologies, Amy Berger, John Kelly, Patrick Lajoie, Qing Shao, Dale Laird

Anatomy and Cell Biology Publications

Connexin 30 (Cx30), a member of the large gap junction protein family, plays a role in the homeostasis of the epidermis and inner ear through gap junctional intercellular communication (GJIC). Here, we investigated the underlying mechanisms of four autosomal dominant Cx30 gene mutations linked to hearing loss and/or various skin diseases. First, the T5M mutant linked to non-syndromic hearing loss formed functional gap junction channels and hemichannels, similar to wild type Cx30. The loss-of-function V37E mutant associated with Clouston syndrome or keratitis-ichthyosis-deafness syndrome was retained in the endoplasmic reticulum and significantly induced apoptosis. The G59R mutant linked to Vohwinkel and …

Incompatibility With Formin Cdc12p Prevents Human Profilin From Substituting For Fission Yeast Profilin: Insights From Crystal Structures Of Fission Yeast Profilin., Obidimma Ezezika, Noah S Younger, Jia Lu, Donald A Kaiser, Zachary A Corbin, Bradley J Nolen, David R Kovar, Thomas D Pollard

Health Studies Publications

Expression of human profilin-I does not complement the temperature-sensitive cdc3-124 mutation of the single profilin gene in fission yeast Schizosaccharomyces pombe, resulting in death from cytokinesis defects. Human profilin-I and S. pombe profilin have similar affinities for actin monomers, the FH1 domain of fission yeast formin Cdc12p and poly-L-proline (Lu, J., and Pollard, T. D. (2001) Mol. Biol. Cell 12, 1161-1175), but human profilin-I does not stimulate actin filament elongation by formin Cdc12p like S. pombe profilin. Two crystal structures of S. pombe profilin and homology models of S. pombe profilin bound to actin show how the two profilins bind …

A Null Mutation For Tissue Inhibitor Of Metalloproteinases-3 (Timp-3) Impairs Murine Bronchiole Branching Morphogenesis., Sean E Gill, M Cynthia Pape, Rama Khokha, Andrew J Watson, Kevin J Leco

Obstetrics & Gynaecology Publications

Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs). We have examined the role of TIMP-3 on ECM homeostasis and bronchiole branching morphogenesis during murine embryogenesis. Employing an in vitro organ culture system, we found decreased bronchiolar branching in null lungs when compared with wild type (WT) counterparts after 2 days in culture. When a synthetic inhibitor of MMPs at low dose was added to the culture system, branching was augmented regardless of genotype. Gelatin and in situ zymography revealed that null lungs exhibited enhanced activation of MMPs throughout lung development. We analysed the impact …