Genetics and Genomics Commons^™

Autolysosomal Exocytosis Of Lipids Protect Neurons From Ferroptosis, Isha Ralhan, Jinlan Chang, Matthew J Moulton, Lindsey D Goodman, Nathanael Y J Lee, Greg Plummer, H Amalia Pasolli, Doreen Matthies, Hugo J Bellen, Maria S Ioannou

Faculty, Staff and Students Publications

During oxidative stress neurons release lipids that are internalized by glia. Defects in this coordinated process play an important role in several neurodegenerative diseases. Yet, the mechanisms of lipid release and its consequences on neuronal health are unclear. Here, we demonstrate that lipid-protein particle release by autolysosome exocytosis protects neurons from ferroptosis, a form of cell death driven by lipid peroxidation. We show that during oxidative stress, peroxidated lipids and iron are released from neurons by autolysosomal exocytosis which requires the exocytic machinery VAMP7 and syntaxin 4. We observe membrane-bound lipid-protein particles by TEM and demonstrate that these particles are …

Machine Learning Reveals Lipidome Remodeling Dynamics In A Mouse Model Of Ovarian Cancer, Olatomiwa O Bifarin, Samyukta Sah, David A Gaul, Samuel G Moore, Ruihong Chen, Murugesan Palaniappan, Jaeyeon Kim, Martin M Matzuk, Facundo M Fernández

Faculty, Staff and Students Publications

Ovarian cancer (OC) is one of the deadliest cancers affecting the female reproductive system. It may present little or no symptoms at the early stages and typically unspecific symptoms at later stages. High-grade serous ovarian cancer (HGSC) is the subtype responsible for most ovarian cancer deaths. However, very little is known about the metabolic course of this disease, particularly in its early stages. In this longitudinal study, we examined the temporal course of serum lipidome changes using a robust HGSC mouse model and machine learning data analysis. Early progression of HGSC was marked by increased levels of phosphatidylcholines and phosphatidylethanolamines. …

The Landscape Of Tolerated Genetic Variation In Humans And Primates, Hong Gao, Tobias Hamp, Jeffrey Ede, Joshua G Schraiber, Jeremy Mcrae, Moriel Singer-Berk, Yanshen Yang, Anastasia S D Dietrich, Petko P Fiziev, Lukas F K Kuderna, Laksshman Sundaram, Yibing Wu, Aashish Adhikari, Yair Field, Chen Chen, Serafim Batzoglou, Francois Aguet, Gabrielle Lemire, Rebecca Reimers, Daniel Balick, Mareike C Janiak, Martin Kuhlwilm, Joseph D Orkin, Shivakumara Manu, Alejandro Valenzuela, Juraj Bergman, Marjolaine Rousselle, Felipe Ennes Silva, Lidia Agueda, Julie Blanc, Marta Gut, Dorien De Vries, Ian Goodhead, R Alan Harris, Muthuswamy Raveendran, Axel Jensen, Idriss S Chuma, Julie E Horvath, Christina Hvilsom, David Juan, Peter Frandsen, Fabiano R De Melo, Fabrício Bertuol, Hazel Byrne, Iracilda Sampaio, Izeni Farias, João Valsecchi Do Amaral, Mariluce Messias, Maria N F Da Silva, Mihir Trivedi, Rogerio Rossi, Tomas Hrbek, Nicole Andriaholinirina, Clément J Rabarivola, Alphonse Zaramody, Clifford J Jolly, Jane Phillips-Conroy, Gregory Wilkerson, Christian Abee, Joe H Simmons, Eduardo Fernandez-Duque, Sree Kanthaswamy, Fekadu Shiferaw, Dongdong Wu, Long Zhou, Yong Shao, Guojie Zhang, Julius D Keyyu, Sascha Knauf, Minh D Le, Esther Lizano, Stefan Merker, Arcadi Navarro, Thomas Bataillon, Tilo Nadler, Chiea Chuen Khor, Jessica Lee, Patrick Tan, Weng Khong Lim, Andrew C Kitchener, Dietmar Zinner, Ivo Gut, Amanda Melin, Katerina Guschanski, Mikkel Heide Schierup, Robin M D Beck, Govindhaswamy Umapathy, Christian Roos, Jean P Boubli, Monkol Lek, Shamil Sunyaev, Anne O'Donnell-Luria, Heidi L Rehm, Jinbo Xu, Jeffrey Rogers, Tomas Marques-Bonet, Kyle Kai-How Farh

Faculty, Staff and Students Publications

INTRODUCTION:

Millions of people have received genome and exome sequencing to date, a collective effort that has illuminated for the first time the vast catalog of small genetic differences that distinguish us as individuals within our species. However, the effects of most of these genetic variants remain unknown, limiting their clinical utility and actionability. New approaches that can accurately discern disease-causing from benign mutations and interpret genetic variants on a genome-wide scale would constitute a meaningful initial step towards realizing the potential of personalized genomic medicine.

RATIONALE:

As a result of the short evolutionary distance between humans and nonhuman primates, …

The Integrative Studies On The Functional A-To-I Rna Editing Events In Human Cancers, Sijia Wu, Zhiwei Fan, Pora Kim, Liyu Huang, Xiaobo Zhou

Faculty, Staff and Student Publications

Adenosine-to-inosine (A-to-I) RNA editing, constituting nearly 90% of all RNA editing events in humans, has been reported to contribute to the tumorigenesis in diverse cancers. However, the comprehensive map for functional A-to-I RNA editing events in cancers is still insufficient. To fill this gap, we systematically and intensively analyzed multiple tumorigenic mechanisms of A-to-I RNA editing events in samples across 33 cancer types from The Cancer Genome Atlas. For individual candidate among ∼ 1,500,000 quantified RNA editing events, we performed diverse types of downstream functional annotations. Finally, we identified 24,236 potentially functional A-to-I RNA editing events, including the cases …

An Fbn1 Deep Intronic Variant Is Associated With Pseudoexon Formation And A Variable Marfan Phenotype In A Five Generation Family, Dong-Chuan Guo, Xueyan Duan, Kathleen Mimnagh, Alana C Cecchi, Isabella C Marin, Yang Yu, Walter V Velasco, Kwanghyuk Lee, Xue Zhu, David R Murdock, Suzanne M Leal, Marsha M Wheeler, Josh Smith, Michael J Bamshad, Dianna M Milewicz

Faculty, Staff and Student Publications

Exome sequencing of genes associated with heritable thoracic aortic disease (HTAD) failed to identify a pathogenic variant in a large family with Marfan syndrome (MFS). A genome-wide linkage analysis for thoracic aortic disease identified a peak at 15q21.1, and genome sequencing identified a novel deep intronic FBN1 variant that segregated with thoracic aortic disease in the family (LOD score 2.7) and was predicted to alter splicing. RT-PCR and bulk RNA sequencing of RNA harvested from fibroblasts explanted from the affected proband revealed an insertion of a pseudoexon between exons 13 and 14 of the FBN1 transcript, predicted to lead to …

Genome-Wide Association Study And Functional Characterization Identifies Candidate Genes For Insulin-Stimulated Glucose Uptake, Alice Williamson, Dougall M Norris, Xianyong Yin, K Alaine Broadaway, Anne H Moxley, Swarooparani Vadlamudi, Emma P Wilson, Anne U Jackson, Vasudha Ahuja, Mette K Andersen, Zorayr Arzumanyan, Lori L Bonnycastle, Stefan R Bornstein, Maxi P Bretschneider, Thomas A Buchanan, Yi-Cheng Chang, Lee-Ming Chuang, Ren-Hua Chung, Tine D Clausen, Peter Damm, Graciela E Delgado, Vanessa D De Mello, Josée Dupuis, Om P Dwivedi, Michael R Erdos, Lilian Fernandes Silva, Timothy M Frayling, Christian Gieger, Mark O Goodarzi, Xiuqing Guo, Stefan Gustafsson, Liisa Hakaste, Ulf Hammar, Gad Hatem, Sandra Herrmann, Kurt Højlund, Katrin Horn, Willa A Hsueh, Yi-Jen Hung, Chii-Min Hwu, Anna Jonsson, Line L Kårhus, Marcus E Kleber, Peter Kovacs, Timo A Lakka, Marie Lauzon, I-Te Lee, Cecilia M Lindgren, Jaana Lindström, Allan Linneberg, Ching-Ti Liu, Jian'an Luan, Dina Mansour Aly, Elisabeth Mathiesen, Angela P Moissl, Andrew P Morris, Narisu Narisu, Nikolaos Perakakis, Annette Peters, Rashmi B Prasad, Roman N Rodionov, Kathryn Roll, Carsten F Rundsten, Chloé Sarnowski, Kai Savonen, Markus Scholz, Sapna Sharma, Sara E Stinson, Sufyan Suleman, Jingyi Tan, Kent D Taylor, Matti Uusitupa, Dorte Vistisen, Daniel R Witte, Romy Walther, Peitao Wu, Anny H Xiang, Björn Zethelius, Emma Ahlqvist, Richard N Bergman, Yii-Der Ida Chen, Francis S Collins, Tove Fall, Jose C Florez, Andreas Fritsche, Harald Grallert, Leif Groop, Torben Hansen, Heikki A Koistinen, Pirjo Komulainen, Markku Laakso, Lars Lind, Markus Loeffler, Winfried März, James B Meigs, Leslie J Raffel, Rainer Rauramaa, Jerome I Rotter, Peter E H Schwarz, Michael Stumvoll, Johan Sundström, Anke Tönjes, Tiinamaija Tuomi, Jaakko Tuomilehto, Robert Wagner, Inês Barroso, Mark Walker, Niels Grarup, Michael Boehnke, Nicholas J Wareham, Karen L Mohlke, Eleanor Wheeler, Stephen O'Rahilly, Daniel J Fazakerley, Claudia Langenberg

Faculty, Staff and Student Publications

Distinct tissue-specific mechanisms mediate insulin action in fasting and postprandial states. Previous genetic studies have largely focused on insulin resistance in the fasting state, where hepatic insulin action dominates. Here we studied genetic variants influencing insulin levels measured 2 h after a glucose challenge in >55,000 participants from three ancestry groups. We identified ten new loci (P < 5 × 10-8) not previously associated with postchallenge insulin resistance, eight of which were shown to share their genetic architecture with type 2 diabetes in colocalization analyses. We investigated candidate genes at a subset of associated loci in cultured cells and identified nine candidate genes newly implicated in the expression or trafficking of GLUT4, the key glucose transporter in postprandial glucose uptake in muscle and fat. By focusing on postprandial insulin resistance, we highlighted the mechanisms of action at type 2 diabetes loci that are not adequately captured by studies of fasting glycemic traits.

Impact Of Cross-Ancestry Genetic Architecture On Gwass In Admixed Populations, Rachel Mester, Kangcheng Hou, Yi Ding, Gillian Meeks, Kathryn S Burch, Arjun Bhattacharya, Brenna M Henn, Bogdan Pasaniuc

Faculty, Staff and Student Publications

Genome-wide association studies (GWASs) have identified thousands of variants for disease risk. These studies have predominantly been conducted in individuals of European ancestries, which raises questions about their transferability to individuals of other ancestries. Of particular interest are admixed populations, usually defined as populations with recent ancestry from two or more continental sources. Admixed genomes contain segments of distinct ancestries that vary in composition across individuals in the population, allowing for the same allele to induce risk for disease on different ancestral backgrounds. This mosaicism raises unique challenges for GWASs in admixed populations, such as the need to correctly adjust …

Bi-Allelic Variants In Hmgcr Cause An Autosomal-Recessive Progressive Limb-Girdle Muscular Dystrophy, Joel A Morales-Rosado, Tanya L Schwab, Sarah K Macklin-Mantia, A Reghan Foley, Filippo Pinto E Vairo, Davut Pehlivan, Sandra Donkervoort, Jill A Rosenfeld, Grace E Boyum, Ying Hu, Anh T Q Cong, Timothy E Lotze, Carrie A Mohila, Dimah Saade, Diana Bharucha-Goebel, Katherine R Chao, Christopher Grunseich, Christine C Bruels, Hannah R Littel, Elicia A Estrella, Lynn Pais, Peter B Kang, Michael T Zimmermann, James R Lupski, Brendan Lee, Matthew J Schellenberg, Karl J Clark, Klaas J Wierenga, Carsten G Bönnemann, Eric W Klee

Faculty, Staff and Students Publications

Statins are a mainstay intervention for cardiovascular disease prevention, yet their use can cause rare severe myopathy. HMG-CoA reductase, an essential enzyme in the mevalonate pathway, is the target of statins. We identified nine individuals from five unrelated families with unexplained limb-girdle like muscular dystrophy and bi-allelic variants in HMGCR via clinical and research exome sequencing. The clinical features resembled other genetic causes of muscular dystrophy with incidental high CPK levels (>1,000 U/L), proximal muscle weakness, variable age of onset, and progression leading to impaired ambulation. Muscle biopsies in most affected individuals showed non-specific dystrophic changes with non-diagnostic immunohistochemistry. …

Impact Of Race And Ethnicity On Presentation And Outcomes Of Patients Treated On Rhabdomyosarcoma Clinical Trials: A Report From The Children’S Oncology Group, Senna R Munnikhuysen, Princess A Ekpo, Wei Xue, Zhengya Gao, Philip J Lupo, Rajkumar Venkatramani, Christine M Heske

Faculty, Staff and Students Publications

BACKGROUND: Racial and ethnic disparities have been demonstrated in pediatric and adult cancers. However, there is no consensus on whether such disparities exist in the presentation, treatment, and outcome of patients with rhabdomyosarcoma (RMS).

METHODS: Patient information from the seven most recent RMS clinical trials was obtained from the Children's Oncology Group (COG). Chi-squared analyses were used to compare patient, tumor, and treatment characteristics across racial and ethnic groups. Pairwise analyses comparing Non-Hispanic Black (NHB) versus Non-Hispanic White (NHW) racial groups and Hispanic versus NHW ethnic groups were conducted for significant characteristics. Kaplan-Meier method and Wilcoxon signed-rank tests were performed …

Optimising Clinical Care Through Cdh1-Specific Germline Variant Curation: Improvement Of Clinical Assertions And Updated Curation Guidelines, Xi Luo, Jamie L Maciaszek, Bryony A Thompson, Huei San Leong, Katherine Dixon, Sónia Sousa, Michael Anderson, Maegan E Roberts, Kristy Lee, Amanda B Spurdle, Arjen R Mensenkamp, Terra Brannan, Carolina Pardo, Liying Zhang, Tina Pesaran, Sainan Wei, Grace-Ann Fasaye, Chimene Kesserwan, Brian H Shirts, Jeremy L Davis, Carla Oliveira, Sharon E Plon, Kasmintan A Schrader, Rachid Karam, Clingen Cdh1 Variant Curation Expert Panel

Faculty, Staff and Students Publications

BACKGROUND: Germline pathogenic variants in CDH1 are associated with increased risk for diffuse gastric cancer and lobular breast cancer. Risk-reduction strategies include consideration of prophylactic surgery, thereby making accurate interpretation of germline CDH1 variants critical for physicians deciding upon these procedures. The Clinical Genome Resource (ClinGen) CDH1 Variant Curation Expert Panel (VCEP) developed specifications for CDH1 variant curation with a goal to resolve variants of uncertain significance (VUS) and with ClinVar conflicting interpretations and continues to update these specifications.

METHODS:CDH1 variant classification specifications were modified based on updated genetic testing clinical criteria, new recommendations from ClinGen, and expert knowledge …

Comprehensive Ecg Reference Intervals In C57bl/6n Substrains Provide A Generalizable Guide For Cardiac Electrophysiology Studies In Mice, Manuela A Oestereicher, Janine M Wotton, Shinya Ayabe, Ghina Bou About, Tsz Kwan Cheng, Jae-Hoon Choi, Dave Clary, Emily M Dew, Lahcen Elfertak, Alain Guimond, Hamed Haseli Mashhadi, Jason D Heaney, Lois Kelsey, Piia Keskivali-Bond, Federico Lopez Gomez, Susan Marschall, Michael Mcfarland, Hamid Meziane, Violeta Munoz Fuentes, Ki-Hoan Nam, Zuzana Nichtová, Dale Pimm, Lynette Bower, Jan Prochazka, Jan Rozman, Luis Santos, Michelle Stewart, Nobuhiko Tanaka, Christopher S Ward, Amelia M E Willett, Robert Wilson, Robert E Braun, Mary E Dickinson, Ann M Flenniken, Yann Herault, K C Kent Lloyd, Ann-Marie Mallon, Colin Mckerlie, Stephen A Murray, Lauryl M J Nutter, Radislav Sedlacek, Je Kyung Seong, Tania Sorg, Masaru Tamura, Sara Wells, Elida Schneltzer, Helmut Fuchs, Valerie Gailus-Durner, Martin Hrabe De Angelis, Jacqueline K White, Nadine Spielmann

Faculty, Staff and Students Publications

Reference ranges provide a powerful tool for diagnostic decision-making in clinical medicine and are enormously valuable for understanding normality in pre-clinical scientific research that uses in vivo models. As yet, there are no published reference ranges for electrocardiography (ECG) in the laboratory mouse. The first mouse-specific reference ranges for the assessment of electrical conduction are reported herein generated from an ECG dataset of unprecedented scale. International Mouse Phenotyping Consortium data from over 26,000 conscious or anesthetized C57BL/6N wildtype control mice were stratified by sex and age to develop robust ECG reference ranges. Interesting findings include that heart rate and key …

Discordant Calls Across Genotype Discovery Approaches Elucidate Variants With Systematic Errors, Elizabeth G Atkinson, Mykyta Artomov, Alexander A Loboda, Heidi L Rehm, Daniel G Macarthur, Konrad J Karczewski, Benjamin M Neale, Mark J Daly

Faculty, Staff and Students Publications

Large-scale high-throughput sequencing data sets have been transformative for informing clinical variant interpretation and for use as reference panels for statistical and population genetic efforts. Although such resources are often treated as ground truth, we find that in widely used reference data sets such as the Genome Aggregation Database (gnomAD), some variants pass gold-standard filters, yet are systematically different in their genotype calls across genotype discovery approaches. The inclusion of such discordant sites in study designs involving multiple genotype discovery strategies could bias results and lead to false-positive hits in association studies owing to technological artifacts rather than a true …

The Voltage-Gated Sodium Channel In Drosophila, Para, Localizes To Dendrites As Well As Axons In Mechanosensitive Chordotonal Neurons, Thomas A Ravenscroft, Ashleigh Jacobs, Mingxue Gu, Daniel F Eberl, Hugo J Bellen

Faculty, Staff and Students Publications

The fruit fly Drosophila melanogaster has provided important insights into how sensory information is transduced by transient receptor potential (TRP) channels in the peripheral nervous system (PNS). However, TRP channels alone have not been able to completely model mechanosensitive transduction in mechanoreceptive chordotonal neurons (CNs). Here, we show that, in addition to TRP channels, the sole voltage-gated sodium channel (NaV) in Drosophila, Para, is localized to the dendrites of CNs. Para is localized to the distal tip of the dendrites in all CNs, from embryos to adults, and is colocalized with the mechanosensitive TRP channels No mechanoreceptor potential C …

Declining Autozygosity Over Time: An Exploration In Over 1 Million Individuals From Three Diverse Cohorts, Sarah M C Colbert, Frank R Wendt, Gita A Pathak, Drew A Helmer, Elizabeth R Hauser, Matthew C Keller, Renato Polimanti, Emma C Johnson

Faculty, Staff and Students Publications

Previous studies have hypothesized that autozygosity is decreasing over generational time. However, these studies were limited to relatively small samples (n < 11,000) lacking in diversity, which may limit the generalizability of their findings. We present data that partially support this hypothesis from three large cohorts of diverse ancestries, two from the US (All of Us, n = 82,474; the Million Veteran Program, n = 622,497) and one from the UK (UK Biobank, n = 380,899). Our results from a mixed-effect meta-analysis demonstrate an overall trend of decreasing autozygosity over generational time (meta-analyzed slope = -0.029, SE = 0.009, p = 6.03e-4). On the basis of our estimates, we would predict F

Snv/Indel Hypermutator Phenotype In Biallelic Rad51c Variant: Fanconi Anemia, Roni Zemet, Haowei Du, Tomasz Gambin, James R Lupski, Pengfei Liu, Paweł Stankiewicz

Faculty, Staff and Students Publications

We previously reported a fetus with Fanconi anemia (FA), complementation group O due to compound heterozygous variants involving RAD51C. Interestingly, the trio exome sequencing analysis also detected eight apparent de novo mosaic variants with variant allele fraction (VAF) ranging between 11.5 and 37%. Here, using whole genome sequencing and a 'home-brew' variant filtering pipeline and DeepMosaic module, we investigated the number and signature of de novo heterozygous and mosaic variants and the hypothesis of a rare phenomenon of hypermutation. Eight-hundred-thirty apparent de novo SNVs and 21 de novo indels had VAFs below 37.41% and were considered postzygotic somatic mosaic variants. …

The Nanoflow Repository, Jessie E Arce, Joshua A Welsh, Sean Cook, John Tigges, Ionita Ghiran, Jennifer C Jones, Andrew Jackson, Matthew Roth, Aleksandar Milosavljevic

Faculty, Staff and Students Publications

Motivation

Extracellular particles (EPs) are the focus of a rapidly growing area of exploration due to the widespread interest in understanding their roles in health and disease. However, despite the general need for EP data sharing and established community standards for data reporting, no standard repository for EP flow cytometry data captures rigor and minimum reporting standards such as those defined by MIFlowCyt-EV (https://doi.org/10.1080/20013078.2020.1713526). We sought to address this unmet need by developing the NanoFlow Repository.

Results

We have developed The NanoFlow Repository to provide the first implementation of the MIFlowCyt-EV framework.

Availability and implementation

The NanoFlow Repository …

Tau Polarizes An Aging Transcriptional Signature To Excitatory Neurons And Glia, Timothy Wu, Jennifer M Deger, Hui Ye, Caiwei Guo, Justin Dhindsa, Brandon T Pekarek, Rami Al-Ouran, Zhandong Liu, Ismael Al-Ramahi, Juan Botas, Joshua M Shulman

Faculty, Staff and Students Publications

Aging is a major risk factor for Alzheimer’s disease (AD), and cell-type vulnerability underlies its characteristic clinical manifestations. We have performed longitudinal, single-cell RNA-sequencing in Drosophila with pan-neuronal expression of human tau, which forms AD neurofibrillary tangle pathology. Whereas tau- and aging-induced gene expression strongly overlap (93%), they differ in the affected cell types. In contrast to the broad impact of aging, tau-triggered changes are strongly polarized to excitatory neurons and glia. Further, tau can either activate or suppress innate immune gene expression signatures in a cell-type-specific manner. Integration of cellular abundance and gene expression pinpoints nuclear factor kappa B …

Tp53 Germline Pathogenic Variant Frequency In Anaplastic Rhabdomyosarcoma: A Children’S Oncology Group Report, Douglas Fair, Luke Maese, Yueh-Yun Chi, Minjie Li, Douglas S Hawkins, Rajkumar Venkatramani, Erin Rudzinski, David Parham, Lisa Teot, David Malkin, Sharon E Plon, He Li, Aniko Sabo, Philip J Lupo, Joshua D Schiffman

Faculty, Staff and Students Publications

Rhabdomyosarcoma (RMS) is a well-described cancer in Li-Fraumeni syndrome, resulting from germline TP53 pathogenic variants (PVs). RMS exhibiting anaplasia (anRMS) are associated with a high rate of germline TP53 PVs. This study provides updated estimates of the prevalence of TP53 germline PVs in RMS (3%) and anRMS (11%) from a large cohort (n = 239) enrolled in five Children's Oncology Group (COG) clinical trials. Although the prevalence of germline TP53 PVs in patients with anRMS in this series is much lower than previously reported, this prevalence remains elevated. Germline evaluation for TP53 PVs should be strongly considered in patients with …

Functional Variants Identify Sex-Specific Genes And Pathways In Alzheimer’S Disease, Thomas Bourquard, Kwanghyuk Lee, Ismael Al-Ramahi, Minh Pham, Dillon Shapiro, Yashwanth Lagisetty, Shirin Soleimani, Samantha Mota, Kevin Wilhelm, Maryam Samieinasab, Young Won Kim, Eunna Huh, Jennifer Asmussen, Panagiotis Katsonis, Juan Botas, Olivier Lichtarge

Faculty, Staff and Students Publications

The incidence of Alzheimer's Disease in females is almost double that of males. To search for sex-specific gene associations, we build a machine learning approach focused on functionally impactful coding variants. This method can detect differences between sequenced cases and controls in small cohorts. In the Alzheimer's Disease Sequencing Project with mixed sexes, this approach identified genes enriched for immune response pathways. After sex-separation, genes become specifically enriched for stress-response pathways in male and cell-cycle pathways in female. These genes improve disease risk prediction in silico and modulate Drosophila neurodegeneration in vivo. Thus, a general approach for machine learning on …

Dna Supercoiling-Induced Shapes Alter Minicircle Hydrodynamic Properties, Radost Waszkiewicz, Maduni Ranasinghe, Jonathan M Fogg, Daniel J Catanese, Maria L Ekiel-Jeżewska, Maciej Lisicki, Borries Demeler, Lynn Zechiedrich, Piotr Szymczak

Faculty, Staff and Students Publications

DNA in cells is organized in negatively supercoiled loops. The resulting torsional and bending strain allows DNA to adopt a surprisingly wide variety of 3-D shapes. This interplay between negative supercoiling, looping, and shape influences how DNA is stored, replicated, transcribed, repaired, and likely every other aspect of DNA activity. To understand the consequences of negative supercoiling and curvature on the hydrodynamic properties of DNA, we submitted 336 bp and 672 bp DNA minicircles to analytical ultracentrifugation (AUC). We found that the diffusion coefficient, sedimentation coefficient, and the DNA hydrodynamic radius strongly depended on circularity, loop length, and degree of …

Bi-Allelic Variants In Ints11 Are Associated With A Complex Neurological Disorder, Burak Tepe, Erica L Macke, Marcello Niceta, Monika Weisz Hubshman, Oguz Kanca, Laura Schultz-Rogers, Yuri A Zarate, G Bradley Schaefer, Jorge Luis Granadillo De Luque, Daniel J Wegner, Benjamin Cogne, Brigitte Gilbert-Dussardier, Xavier Le Guillou, Eric J Wagner, Lynn S Pais, Jennifer E Neil, Ganeshwaran H Mochida, Christopher A Walsh, Nurit Magal, Valerie Drasinover, Mordechai Shohat, Tanya Schwab, Chris Schmitz, Karl Clark, Anthony Fine, Brendan Lanpher, Ralitza Gavrilova, Pierre Blanc, Lydie Burglen, Alexandra Afenjar, Dora Steel, Manju A Kurian, Prab Prabhakar, Sophie Gößwein, Nataliya Di Donato, Enrico S Bertini, Undiagnosed Diseases Network, Michael F Wangler, Shinya Yamamoto, Marco Tartaglia, Eric W Klee, Hugo J Bellen

Faculty, Staff and Students Publications

The Integrator complex is a multi-subunit protein complex that regulates the processing of nascent RNAs transcribed by RNA polymerase II (RNAPII), including small nuclear RNAs, enhancer RNAs, telomeric RNAs, viral RNAs, and protein-coding mRNAs. Integrator subunit 11 (INTS11) is the catalytic subunit that cleaves nascent RNAs, but, to date, mutations in this subunit have not been linked to human disease. Here, we describe 15 individuals from 10 unrelated families with bi-allelic variants in INTS11 who present with global developmental and language delay, intellectual disability, impaired motor development, and brain atrophy. Consistent with human observations, we find that the fly ortholog …

Association Of Mitochondrial Dna Copy Number With Brain Mri Markers And Cognitive Function: A Meta-Analysis Of Community-Based Cohorts, Yuankai Zhang, Xue Liu, Kerri L Wiggins, Nuzulul Kurniansyah, Xiuqing Guo, Amanda L Rodrigue, Wei Zhao, Lisa R Yanek, Scott M Ratliff, Achilleas Pitsillides, Juan Sebastian Aguirre Patiño, Tamar Sofer, Dan E Arking, Thomas R Austin, Alexa S Beiser, John Blangero, Eric Boerwinkle, Jan Bressler, Joanne E Curran, Lifang Hou, Timothy M Hughes, Sharon L R Kardia, Lenore J Launer, Daniel Levy, Thomas H Mosley, Ilya M Nasrallah, Stephen S Rich, Jerome I Rotter, Sudha Seshadri, Wassim Tarraf, Kevin A González, Vasan Ramachandran, Kristine Yaffe, Paul A Nyquist, Bruce M Psaty, Charles S Decarli, Jennifer A Smith, David C Glahn, Hector M González, Joshua C Bis, Myriam Fornage, Susan R Heckbert, Annette L Fitzpatrick, Chunyu Liu, Claudia L Satizabal

Faculty, Staff and Student Publications

BACKGROUND AND OBJECTIVES: Previous studies suggest that lower mitochondrial DNA (mtDNA) copy number (CN) is associated with neurodegenerative diseases. However, whether mtDNA CN in whole blood is related to endophenotypes of Alzheimer disease (AD) and AD-related dementia (AD/ADRD) needs further investigation. We assessed the association of mtDNA CN with cognitive function and MRI measures in community-based samples of middle-aged to older adults.

METHODS: We included dementia-free participants from 9 diverse community-based cohorts with whole-genome sequencing in the Trans-Omics for Precision Medicine (TOPMed) program. Circulating mtDNA CN was estimated as twice the ratio of the average coverage of mtDNA to nuclear …

Very-Long-Chain Fatty Acids Induce Glial-Derived Sphingosine-1-Phosphate Synthesis, Secretion, And Neuroinflammation, Hyung-Lok Chung, Qi Ye, Ye-Jin Park, Zhongyuan Zuo, Jung-Wan Mok, Oguz Kanca, Sudhir Gopal Tattikota, Shenzhao Lu, Nobert Perrimon, Hyun Kyoung Lee, Hugo J Bellen

Faculty, Staff and Students Publications

VLCFAs (very-long-chain fatty acids) are the most abundant fatty acids in myelin. Hence, during demyelination or aging, glia are exposed to higher levels of VLCFA than normal. We report that glia convert these VLCFA into sphingosine-1-phosphate (S1P) via a glial-specific S1P pathway. Excess S1P causes neuroinflammation, NF-κB activation, and macrophage infiltration into the CNS. Suppressing the function of S1P in fly glia or neurons, or administration of Fingolimod, an S1P receptor antagonist, strongly attenuates the phenotypes caused by excess VLCFAs. In contrast, elevating the VLCFA levels in glia and immune cells exacerbates these phenotypes. Elevated VLCFA and S1P are also …

Unique Transcriptional Profiles Underlie Osteosarcomagenesis Driven By Different P53 Mutants, Dhruv Chachad

Dissertations and Theses (Open Access)

Missense mutations in the DNA binding domain of the Trp53 gene are characterized as structural (p53R172H) or contact (p53R245W) mutations based on their effect on the conformation of the protein. These mutations show gain-of-function activities such as increased metastatic incidence as compared to p53 loss, often mediated by their interaction with a repertoire of transcription factors. These interactions are largely context specific. In order to understand the mechanisms by which these mutations drive osteosarcoma progression, we created a mouse model, wherein either the p53 structural mutant p53R172H, or the contact mutant, p53R245W, are expressed specifically in …

P53 Dimers Elicit Unique Tumor Suppressive Activities Through An Altered Metabolic Program, Jovanka Gencel-Augusto

Dissertations and Theses (Open Access)

p53 is the most frequently mutated tumor suppressor in human cancer. As a tetrameric transcription factor, mutation of the p53 Tetramerization Domain (TD) is a mechanism by which cancers abrogate wild-type (WT) p53 function. p53 TD mutations result in a protein that preferentially forms monomers or dimers. These are also normal p53 states under basal cellular conditions. Although it is accepted that tetrameric p53 is required for full tumor suppressive activities, the physiological relevance of monomeric and dimeric states of p53 is not well understood. We have established in vivo models for monomeric and dimeric p53 which model Li-Fraumeni Syndrome …

Reconstructing Mutational Lineages In Breast Cancer By Multi-Patient-Targeted Single Cell Dna Sequencing, Jake Leighton

Dissertations and Theses (Open Access)

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer with high rates of metastasis and recurrence, where TNBC patients have a poor 5-year survival and ~50% are non-responsive to chemotherapy. Aneuploidy is a cancer hallmark that is pervasive in over 90% of breast cancer patients and is indicative of complex genomic rearrangements that are acquired during tumor initiation. Although copy number aberrations have been extensively studied in relation to aneuploidy and TNBC initiation, little is currently known regarding the timing and impact of single nucleotide variants (SNVs) contributing to these early transformative genomic events. Paramount to novel …

The Diagnostic Odyssey Of Hypermobile Eds Patients: Diagnosis, Clinical Expectations, And Psychosocial Concerns, Madeline Alpar

Dissertations and Theses (Open Access)

Background: Ehlers-Danlos syndrome (EDS) is a highly variable, heritable connective tissue disorder. Hypermobile EDS (hEDS) is the most common subtype of EDS and has no identifiable underlying genetic etiology. Patients with clinical features of hEDS face a long diagnostic odyssey due to lack of genetic testing and wide clinical heterogeneity. Additionally, recent research has shown that genetic institutions limit evaluations for suspected hEDS, adding another barrier to care.

Methods: We developed an online patient survey to explore the diagnostic odyssey of hEDS for those who were diagnosed with or suspicious for hEDS. This survey included sections on demographics, diagnostic information …

Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw

Dissertations and Theses (Open Access)

Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …

Deephtlv: A Deep Learning Framework For Detecting Human T-Lymphotrophic Virus 1 Integration Sites, Johnathan Jia, Johnathan Jia

Dissertations and Theses (Open Access)

In the 1980s, researchers found the first human oncogenic retrovirus called human T-lymphotrophic virus type 1 (HTLV-1). Since then, HTLV-1 has been identified as the causative agent behind several diseases such as adult T-cell leukemia/lymphoma (ATL) and a HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM/TSP). As part of its normal replication cycle, the genome is converted into DNA and integrated into the genome. With several hundreds to thousands of unique viral integration sites (VISs) distributed with indeterminate preference throughout the genome, detection of HTLV-1 VISs is a challenging task. Experimental studies typically use molecular biology …

Regulation Of De Novo And Maintenance Dna Methylation By Dnmt3a And Dnmt3b, Yang Zeng

Dissertations and Theses (Open Access)

DNA methylation (5-methylcytosine, 5mC) is essential for the regulation of gene expression and integrity of the mammalian genome. It occurs predominantly in the context of CpG dinucleotides to form a symmetrical pattern on both DNA strands, which allows DNA methylation patterns to be semi-conservatively maintained during DNA replication. There are two classes of DNA methyltransferases (DNMTs): DNMT3A and DNMT3B function primarily as de novo methyltransferases that establish DNA methylation patterns, whereas DNMT1 is the major enzyme responsible for maintaining DNA methylation patterns by converting hemi-methylated CpGs to fully methylated CpGs during DNA replication. Two accessory factors also play critical regulatory …