Genetic Processes Commons^™

Defects In Lipid Homeostasis Reflect The Function Of Tango2 In Phospholipid And Neutral Lipid Metabolism, Agustin Leonardo Lujan, Ombretta Foresti, Conor Sugden, Nathalie Brouwers, Alex Mateo Farre, Alessio Vignoli, Mahshid Azamian, Alicia Turner, Jose Wojnacki, Vivek Malhotra

Faculty, Staff and Students Publications

We show that TANGO2 in mammalian cells localizes predominantly to mitochondria and partially at mitochondria sites juxtaposed to lipid droplets (LDs) and the endoplasmic reticulum. HepG2 cells and fibroblasts of patients lacking TANGO2 exhibit enlarged LDs. Quantitative lipidomics revealed a marked increase in lysophosphatidic acid (LPA) and a concomitant decrease in its biosynthetic precursor phosphatidic acid (PA). These changes were exacerbated in nutrient-starved cells. Based on our data, we suggest that TANGO2 function is linked to acyl-CoA metabolism, which is necessary for the acylation of LPA to generate PA. The defect in acyl-CoA availability impacts the metabolism of many other …

Access To Clinically Indicated Genetic Tests For Pediatric Patients With Medicaid: Evidence From Outpatient Genetics Clinics In Texas, Haley Streff, Crescenda L Uhles, Heather Fisher, Rachel Franciskovich, Rebecca O Littlejohn, Amanda Gerard, Julianna Hudnall, Hadley Stevens Smith

Faculty, Staff and Students Publications

Purpose: Little is known about how Medicaid coverage policies affect access to genetic tests for pediatric patients. Building upon and extending a previous analysis of prior authorization requests (PARs), we describe expected coverage of genetic tests submitted to Texas Medicaid and the PAR and diagnostic outcomes of those tests.

Methods: We retrospectively reviewed genetic tests ordered at 3 pediatric outpatient genetics clinics in Texas. We compared Current Procedural Terminology (CPT) codes with the Texas Medicaid fee-for-service schedule (FFSS) to determine whether tests were expected to be covered by Medicaid. We assessed completion and diagnostic yield of commonly ordered tests.

Results: …

Cognitive And Academic Performance Of Rural Zambian Youth Exposed To Hiv, Sophie Jago, Joseph Mwaba Chirwa, Mei Tan, Philip E Thuma, Elena L Grigorenko

Faculty, Staff and Students Publications

Studies focusing on children affected by HIV have shown that they have generally lower academic performance, however, few studies separate children who are HIV exposed and infected (CHEI) and those who are HIV exposed but uninfected (CHEU). Importantly, in rural sub-Saharan Africa, the majority of studies on CHEI and CHEU examine academic performance indirectly based on cognitive test scores. Therefore, studies assessing the effects of HIV on academic achievement directly for CHEI and CHEU are needed. This article evaluates the effects of HIV-infection on cognitive and academic performance by comparing CHEI (n = 82) and CHEU (n = 1045) aged …

B-Complex Vitamins For Patients With Tango2-Deficiency Disorder, Sarah E Sandkuhler, Lilei Zhang, Joshua K Meisner, Lina Ghaloul-Gonzalez, Cheyenne M Beach, David Harris, Pascale De Lonlay, Seema R Lalani, Christina Y Miyake, Samuel J Mackenzie

Faculty, Staff and Students Publications

No abstract provided.

Does The Potocki-Lupski Syndrome Convey The Autism Spectrum Disorder Phenotype? Case Report And Scoping Review, Oksana I Talantseva, Galina V Portnova, Raisa S Romanova, Daria A Martynova, Olga V Sysoeva, Elena L Grigorenko

Faculty, Staff and Students Publications

Potocki-Lupski Syndrome (PTLS) is a rare condition associated with a duplication of 17p11.2 that may underlie a wide range of congenital abnormalities and heterogeneous behavioral phenotypes. Along with developmental delay and intellectual disability, autism-specific traits are often reported to be the most common among patients with PTLS. To contribute to the discussion of the role of autism spectrum disorder (ASD) in the PTLS phenotype, we present a case of a female adolescent with a de novo dup(17) (p11.2p11.2) without ASD features, focusing on in-depth clinical, behavioral, and electrophysiological (EEG) evaluations. Among EEG features, we found the atypical peak-slow wave patterns …

Parp1 Associates With R-Loops To Promote Their Resolution And Genome Stability, Natalie Laspata, Parminder Kaur, Sofiane Yacine Mersaoui, Daniela Muoio, Zhiyan Silvia Liu, Maxwell Henry Bannister, Hai Dang Nguyen, Caroline Curry, John M. Pascal, Guy G. Poirier, Hong Wang, Jean-Yves Masson, Elise Fouquerel

Student Papers, Posters & Projects

PARP1 is a DNA-dependent ADP-Ribose transferase with ADP-ribosylation activity that is triggered by DNA breaks and non-B DNA structures to mediate their resolution. PARP1 was also recently identified as a component of the R-loop-associated protein-protein interaction network, suggesting a potential role for PARP1 in resolving this structure. R-loops are three-stranded nucleic acid structures that consist of a RNA-DNA hybrid and a displaced non-template DNA strand. R-loops are involved in crucial physiological processes but can also be a source of genome instability if persistently unresolved. In this study, we demonstrate that PARP1 binds R-loops in vitro and associates with R-loop formation …

Metabolic Individuality: Limitations, Challenges, And Potential For Clinical Utility, Sarah H Elsea, Jennifer E Posey

Faculty, Staff and Students Publications

In Nature Medicine, Surendran and colleagues recently reported the analysis of human plasma metabolomic data for 913 metabolites in ∼20,000 individuals, identifying 2,599 metabolite-genetic variant associations and >400 metabolite signatures comprised of jointly regulated metabolites. This extensive atlas of variant-metabolite relationships reveals novel genomic mechanisms driving metabolic phenotypes.

Solid Organ Transplantation In Methylmalonic Acidemia And Propionic Acidemia: A Points To Consider Statement Of The American College Of Medical Genetics And Genomics (Acmg), Kuntal Sen, Lindsay C Burrage, Kimberly A Chapman, Ilona Ginevic, George V Mazariegos, Brett H Graham, Acmg Therapeutics Committe

Faculty, Staff and Students Publications

No abstract provided.

Biallelic Variants In Hect E3 Paralogs, Hectd4 And Ube3c, Encoding Ubiquitin Ligases Cause Neurodevelopmental Disorders That Overlap With Angelman Syndrome, Eissa A Faqeih, Malak Ali Alghamdi, Marwa A Almahroos, Essa Alharby, Makki Almuntashri, Amnah M Alshangiti, Prouteau Clément, Daniel G Calame, Leila Qebibo, Lydie Burglen, Martine Doco-Fenzy, Mario Mastrangelo, Annalaura Torella, Filippo Manti, Vincenzo Nigro, Ziegler Alban, Ghadeer Saleh Alharbi, Jamil Amjad Hashmi, Rawya Alraddadi, Razan Alamri, Tadahiro Mitani, Barth Magalie, Zeynep Coban-Akdemir, Bilgen Bilge Geckinli, Davut Pehlivan, Antonio Romito, Vasiliki Karageorgou, Javier Martini, Estelle Colin, Dominique Bonneau, Aida Bertoli-Avella, James R Lupski, Annalisa Pastore, Roy W A Peake, Ashraf Dallol, Majid Alfadhel, Naif A M Almontashiri

Faculty, Staff and Students Publications

Purpose: Pathogenic variants in genes encoding ubiquitin E3 ligases are known to cause neurodevelopmental syndromes. Additional neurodevelopmental disorders associated with the other genes encoding E3 ligases are yet to be identified.

Methods: Chromosomal analysis and exome sequencing were used to identify the genetic causes in 10 patients from 7 unrelated families with syndromic neurodevelopmental, seizure, and movement disorders and neurobehavioral phenotypes.

Results: In total, 4 patients were found to have 3 different homozygous loss-of-function (LoF) variants, and 3 patients had 4 compound heterozygous missense variants in the candidate E3 ligase gene, HECTD4, that were rare, absent from controls as homozygous, …

Exploring Genetic And Neural Risk Of Specific Reading Disability Within A Nuclear Twin Family Case Study: A Translational Clinical Application, Tina Thomas, Griffin Litwin, David J Francis, Elena L Grigorenko

Faculty, Staff and Students Publications

Imaging and genetic studies have characterized biological risk factors contributing to specific reading disability (SRD). The current study aimed to apply this literature to a family of twins discordant for SRD and an older sibling with reading difficulty. Intraclass correlations were used to understand the similarity of imaging phenotypes between pairs. Reading-related genes and brain region phenotypes, including asymmetry indices representing the relative size of left compared to right hemispheric structures, were descriptively examined. SNPs that corresponded between the SRD siblings and not the typically developing (TD) siblings were in genes ZNF385D, LPHN3, CNTNAP2, FGF18, NOP9 …

Investigation Of The Dyrk1a Regulation By Lzts2-Sipa1l1 Complex, Rebecca Gunnin, Austin Witt B.S., Larisa Litovchick M.D.,Ph.D.

UROP Posters

A region on chromosome 21, the Down Syndrome critical region (DSCR), is associated with major defects found in Down Syndrome, such as craniofacial malformations. DYRK1A is a gene found on chromosome 21 within the DSCR that encodes an enzyme, dual specificity tyrosine-phosphorylation-regulated kinase 1A. DYRK1A is known to phosphorylate many substrate proteins and is thought to be involved in tumor suppression, neurological development, cell cycle regulation, and aging. Recently, the Litovchick lab and others reported that DYRK1A also plays a role in the double-strand break repair of DNA, which could lead to mutations and tumorigenesis, if deregulated.

The Litovchick lab …

Brain Monoamine Vesicular Transport Disease Caused By Homozygous Slc18a2 Variants: A Study In 42 Affected Individuals, Ken Saida, Reza Maroofian, Toru Sengoku, Tadahiro Mitani, Alistair T Pagnamenta, Dana Marafi, Maha S Zaki, Thomas J O'Brien, Ehsan Ghayoor Karimiani, Rauan Kaiyrzhanov, Marina Takizawa, Sachiko Ohori, Huey Yin Leong, Gulsen Akay, Hamid Galehdari, Mina Zamani, Ratna Romy, Christopher J Carroll, Mehran Beiraghi Toosi, Farah Ashrafzadeh, Shima Imannezhad, Hadis Malek, Najmeh Ahangari, Hoda Tomoum, Vykuntaraju K Gowda, Varunvenkat M Srinivasan, David Murphy, Natalia Dominik, Hasnaa M Elbendary, Karima Rafat, Sanem Yilmaz, Seda Kanmaz, Mine Serin, Deepa Krishnakumar, Alice Gardham, Anna Maw, Tekki Sreenivasa Rao, Sarah Alsubhi, Myriam Srour, Daniela Buhas, Tamison Jewett, Rachel E Goldberg, Hanan Shamseldin, Eirik Frengen, Doriana Misceo, Petter Strømme, José Ricardo Magliocco Ceroni, Chong Ae Kim, Gozde Yesil, Esma Sengenc, Serhat Guler, Mariam Hull, Mered Parnes, Dilek Aktas, Banu Anlar, Yavuz Bayram, Davut Pehlivan, Jennifer E Posey, Shahryar Alavi, Seyed Ali Madani Manshadi, Hamad Alzaidan, Mohammad Al-Owain, Lama Alabdi, Ferdous Abdulwahab, Futoshi Sekiguchi, Kohei Hamanaka, Atsushi Fujita, Yuri Uchiyama, Takeshi Mizuguchi, Satoko Miyatake, Noriko Miyake, Reem M Elshafie, Kamran Salayev, Ulviyya Guliyeva, Fowzan S Alkuraya, Joseph G Gleeson, Kristin G Monaghan, Katherine G Langley, Hui Yang, Mahsa Motavaf, Saeid Safari, Mozhgan Alipour, Kazuhiro Ogata, André E X Brown, James R Lupski, Henry Houlden, Naomichi Matsumoto

Faculty, Staff and Students Publications

Purpose: Brain monoamine vesicular transport disease is an infantile-onset movement disorder that mimics cerebral palsy. In 2013, the homozygous SLC18A2 variant, p.Pro387Leu, was first reported as a cause of this rare disorder, and dopamine agonists were efficient for treating affected individuals from a single large family. To date, only 6 variants have been reported. In this study, we evaluated genotype-phenotype correlations in individuals with biallelic SLC18A2 variants.

Methods: A total of 42 affected individuals with homozygous SLC18A2 variant alleles were identified. We evaluated genotype-phenotype correlations and the missense variants in the affected individuals based on the structural modeling of rat …

Editorial: Insights In Neurogenomics: 2022, Aayushi Gandhi, Sarah H Elsea

Faculty, Staff and Students Publications

No abstract provided.

Genetics In Medicine Open To Us All, Bo Yuan

Faculty, Staff and Students Publications

No abstract provided.

Editorial: Neurogenetic Disorders: From The Tests To The Clinic, Shanshan Mao, Chunyu Li, Bo Yuan, Lan Yu, Huifang Shang

Faculty, Staff and Students Publications

No abstract provided.

The Role Of Neural And Genetic Processes In Learning To Read And Specific Reading Disabilities: Implications For Instruction, Jessica A Church, Elena L Grigorenko, Jack M Fletcher

Faculty, Staff and Students Publications

To learn to read, the brain must repurpose neural systems for oral language and visual processing to mediate written language. We begin with a description of computational models for how alphabetic written language is processed. Next, we explain the roles of a dorsal sublexical system in the brain that relates print and speech, a ventral lexical system that develops the visual expertise for rapid orthographic processing at the word level, and the role of cognitive control networks that regulate attentional processes as children read. We then use studies of children, adult illiterates learning to read, and studies of poor readers …

The Global Prevalence Of Autism Spectrum Disorder: A Three-Level Meta-Analysis, Oksana I Talantseva, Raisa S Romanova, Ekaterina M Shurdova, Tatiana A Dolgorukova, Polina S Sologub, Olga S Titova, Daria F Kleeva, Elena L Grigorenko

Faculty, Staff and Students Publications

Autism spectrum disorder (ASD) is one the most disabling developmental disorders, imposing an extremely high economic burden. Obtaining as accurate prevalence estimates as possible is crucial to guide governments in planning policies for identification and intervention for individuals with ASD and their relatives. The precision of prevalence estimates can be heightened by summative analyses of the data collected around the world. To that end, we conducted a three-level mixed-effects meta-analysis. A systematic search of the Web of Science, PubMed, EMBASE, and PsycINFO databases from 2000 up to 13 July 2020 was performed, and reference lists of previous reviews and existing …

Truvari: Refined Structural Variant Comparison Preserves Allelic Diversity, Adam C English, Vipin K Menon, Richard A Gibbs, Ginger A Metcalf, Fritz J Sedlazeck

Faculty, Staff and Students Publications

The fundamental challenge of multi-sample structural variant (SV) analysis such as merging and benchmarking is identifying when two SVs are the same. Common approaches for comparing SVs were developed alongside technologies which produce ill-defined boundaries. As SV detection becomes more exact, algorithms to preserve this refined signal are needed. Here, we present Truvari-an SV comparison, annotation, and analysis toolkit-and demonstrate the effect of SV comparison choices by building population-level VCFs from 36 haplotype-resolved long-read assemblies. We observe over-merging from other SV merging approaches which cause up to a 2.2× inflation of allele frequency, relative to Truvari.

Mechanisms Of Irf2bpl-Related Disorders And Identification Of A Potential Therapeutic Strategy, Shrestha Sinha Ray, Debdeep Dutta, Cassandra Dennys, Samantha Powers, Florence Roussel, Pawel Lisowski, Petar Glažar, Xiaojin Zhang, Pipasha Biswas, Joseph R Caporale, Nikolaus Rajewsky, Marc Bickle, Nicolas Wein, Hugo J Bellen, Shibi Likhite, Paul C Marcogliese, Kathrin C Meyer

Faculty, Staff and Students Publications

The recently discovered neurological disorder NEDAMSS is caused by heterozygous truncations in the transcriptional regulator IRF2BPL. Here, we reprogram patient skin fibroblasts to astrocytes and neurons to study mechanisms of this newly described disease. While full-length IRF2BPL primarily localizes to the nucleus, truncated patient variants sequester the wild-type protein to the cytoplasm and cause aggregation. Moreover, patient astrocytes fail to support neuronal survival in coculture and exhibit aberrant mitochondria and respiratory dysfunction. Treatment with the small molecule copper ATSM (CuATSM) rescues neuronal survival and restores mitochondrial function. Importantly, the in vitro findings are recapitulated in vivo, where co-expression of full-length …

A Recurrent Single-Exon Deletion In Tbck Might Be Under-Recognized In Patients With Infantile Hypotonia And Psychomotor Delay, Hongzheng Dai, Wenmiao Zhu, Bo Yuan, Nicole Walley, Kelly Schoch, Yong-Hui Jiang, John A Phillips, Melissa S Jones, Pengfei Liu, David R Murdock, Lindsay C Burrage, Brendan Lee, Jill A Rosenfeld, Rui Xiao

Faculty, Staff and Students Publications

Advanced bioinformatics algorithms allow detection of multiple-exon copy-number variations (CNVs) from exome sequencing (ES) data, while detection of single-exon CNVs remains challenging. A retrospective review of Baylor Genetics' clinical ES patient cohort identified four individuals with homozygous single-exon deletions of TBCK (exon 23, NM_001163435.2), a gene associated with an autosomal recessive neurodevelopmental phenotype. To evaluate the prevalence of this deletion and its contribution to disease, we retrospectively analyzed single nucleotide polymorphism (SNP) array data for 8194 individuals undergoing ES, followed by PCR confirmation and RT-PCR on individuals carrying homozygous or heterozygous exon 23 TBCK deletions. A fifth individual was diagnosed …

Long Read Sequencing And Expression Studies Of Ahdc1 Deletions In Xia-Gibbs Syndrome Reveal A Novel Genetic Regulatory Mechanism, Varuna Chander, Medhat Mahmoud, Jianhong Hu, Zain Dardas, Christopher M Grochowski, Moez Dawood, Michael M Khayat, He Li, Shoudong Li, Shalini Jhangiani, Viktoriya Korchina, Hua Shen, George Weissenberger, Qingchang Meng, Marie-Claude Gingras, Donna M Muzny, Harsha Doddapaneni, Jennifer E Posey, James R Lupski, Aniko Sabo, David R Murdock, Fritz J Sedlazeck, Richard A Gibbs

Faculty, Staff and Students Publications

Xia-Gibbs syndrome (XGS; MIM# 615829) is a rare mendelian disorder characterized by Development Delay (DD), intellectual disability (ID), and hypotonia. Individuals with XGS typically harbor de novo protein-truncating mutations in the AT-Hook DNA binding motif containing 1 (AHDC1) gene, although some missense mutations can also cause XGS. Large de novo heterozygous deletions that encompass the AHDC1 gene have also been ascribed as diagnostic for the disorder, without substantial evidence to support their pathogenicity. We analyzed 19 individuals with large contiguous deletions involving AHDC1, along with other genes. One individual bore the smallest known contiguous AHDC1 deletion (∼350 Kb), encompassing eight …

Spectrum Of Ddc Variants Causing Aromatic L-Amino Acid Decarboxylase (Aadc) Deficiency And Pathogenicity Interpretation Using Acmg-Amp/Acgs Recommendations, Nastassja Himmelreich, Riccardo Montioli, Sven F Garbade, Jeffrey Kopesky, Sarah H Elsea, Carla Carducci, Carla B Voltattorni, Nenad Blau

Faculty, Staff and Students Publications

Pathogenic variants in dopa decarboxylase (DDC), the gene encoding the aromatic l-amino acid decarboxylase (AADC) enzyme, lead to a severe deficiency of neurotransmitters, resulting in neurological, neuromuscular, and behavioral manifestations clinically characterized by developmental delays, oculogyric crises, dystonia, and severe neurologic dysfunction in infancy. Historically, therapy has been aimed at compensating for neurotransmitter abnormalities, but response to pharmacologic therapy varies, and in most cases, the therapy shows little or no benefit. A novel human DDC gene therapy was recently approved in the European Union that targets the underlying genetic cause of the disorder, providing a new treatment option for patients …

Exome Sequencing Efficacy And Phenotypic Expansions Involving Esophageal Atresia/Tracheoesophageal Fistula Plus, Mary R Sy, Jaynee Chauhan, Katrina Prescott, Aliza Imam, Alison Kraus, Ana Beleza, Lee Salkeld, Saraswati Hosdurga, Michael Parker, Pradeep Vasudevan, Lily Islam, Himanshu Goel, Nicole Bain, Soo-Mi Park, Shehla Mohammed, Klaus Dieterich, Charles Coutton, Véronique Satre, Gaëlle Vieville, Alan Donaldson, Claire Beneteau, Jamal Ghoumid, Kris Van Den Bogaert, Anneleen Boogaerts, Elise Boudry, Clémence Vanlerberghe, Florence Petit, Laura Bernardini, Barbara Torres, Teresa Mattina, Diana Carli, Giorgia Mandrile, Michele Pinelli, Nicola Brunetti-Pierri, Katherine Neas, Rachel Beddow, Pernille M Tørring, Flavio Faletra, Beatrice Spedicati, Paolo Gasparini, Alessandro Mussa, Giovanni Battista Ferrero, Anne Lampe, Wayne Lam, Weimin Bi, Carlos A Bacino, Akela Kuwahara, Jeffrey O Bush, Xiaonan Zhao, Pamela N Luna, Chad A Shaw, Jill A Rosenfeld, Daryl A Scott

Faculty, Staff and Students Publications

Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a life-threatening birth defect that often occurs with other major birth defects (EA/TEF+). Despite advances in genetic testing, a molecular diagnosis can only be made in a minority of EA/TEF+ cases. Here, we analyzed clinical exome sequencing data and data from the DECIPHER database to determine the efficacy of exome sequencing in cases of EA/TEF+ and to identify phenotypic expansions involving EA/TEF. Among 67 individuals with EA/TEF+ referred for clinical exome sequencing, a definitive or probable diagnosis was made in 11 cases for an efficacy rate of 16% (11/67). This efficacy rate is significantly lower …

Growth Parameters In Children With Achondroplasia: A 7-Year, Prospective, Multinational, Observational Study, Ravi Savarirayan, Melita Irving, Paul Harmatz, Borja Delgado, William R Wilcox, John Philips, Natalie Owen, Carlos A Bacino, Louise Tofts, Joel Charrow, Lynda E Polgreen, Julie Hoover-Fong, Paul Arundel, Ignacio Ginebreda, Howard M Saal, Donald Basel, Rosendo Ullot Font, Keiichi Ozono, Michael B Bober, Valerie Cormier-Daire, Kim-Hanh Le Quan Sang, Genevieve Baujat, Yasemin Alanay, Frank Rutsch, Daniel Hoernschemeyer, Klaus Mohnike, Hiroshi Mochizuki, Asako Tajima, Yumiko Kotani, David D Weaver, Klane K White, Clare Army, Kevin Larrimore, Keith Gregg, George Jeha, Claire Milligan, Elena Fisheleva, Alice Huntsman-Labed, Jonathan Day

Faculty, Staff and Students Publications

Purpose: This study was undertaken to collect baseline growth parameters in children with achondroplasia who might enroll in interventional trials of vosoritide, and to establish a historical control.

Methods: In this prospective, observational study, participants (≤17 years) underwent a detailed medical history and physical examination and were followed every 3 months until they finished participating in the study by enrolling in an interventional trial or withdrawing.

Results: A total of 363 children were enrolled (28 centers, 8 countries). Mean (SD) follow up was 20.4 (15.0) months. In participants < 1 year, mean annualized growth velocity (AGV) was 11.6 cm/year for girls and 14.6 cm/year for boys. By age 1 year, mean AGV decreased to 7.4 cm/year in girls and 7.1 cm/year in boys. By age 10 years, mean AGV decreased to 3.6 cm/year for both sexes. Mean height z-score in participants < 1 year was -2.5 for girls and -3.2 for boys and decreased up to the age 5 years (-5.3 for girls; -4.6 for boys). Girls and boys had a disproportionate upper-to-lower body segment ratio. Mean ratio was highest in participants aged < 1 year (2.9 for girls; 2.8 for boys) and decreased gradually to approximately 2 in both sexes from 4 years of age onward.

Conclusion: This study represents one of the largest datasets of prospectively collected …

Conservation And Divergence In The Heterochronic Pathway Of C. Elegans And C. Briggsae, Maria Ivanova, Eric G. Moss

Rowan-Virtua Research Day

The heterochronic pathway of Caenorhabditis elegans is exemplary as a mechanism of developmental timing: mutations in genes of this pathway alter the relative timing of diverse developmental events independent of spatial or cell type specific regulation. It is the most thoroughly characterized developmental timing pathway known. Most of the heterochronic genes are conserved across great evolutionary time, and a few homologs seem to have developmental timing roles in certain contexts. The degree to which other organisms have explicit developmental timing mechanisms, and what factors comprise those mechanisms, isn’t generally known.

Developmental pathways evolve even if the resulting morphology remains the …

Modeling The Role Of Cyclin C In Connecting Stress-Induced Mitochondrial Fission To Apoptosis, Steven J. Doyle, Randy Strich

Rowan-Virtua Research Day

For normal cell function, exogenous signals must be correctly interpreted, and the proper response executed. The mitochondria are key regulatory nodes of cellular fate. For example, mitochondria undergo fission and fusion cycles depending on the energetic needs of the cell. Additionally, regulated cell death pathways also function at the mitochondria. Cyclin C is a transcriptional regulator of stress response and growth control genes. Following stress, a portion of cyclin C translocates to the cytoplasm, where it interacts with both the mitochondrial fission and apoptotic machinery. Based on these findings, we hypothesize that Cyclin C represents a key mediator linking transcription …

Substrate-Specific Effect On Sirtuin Conformation And Oligomerization, Jie Yang, Shannon L. Dwyer, Nathan I. Nicely, Brian P. Weiser

Rowan-Virtua Research Day

Human sirtuins are a family of nicotinamide adenine dinucleotide (NAD +)-dependent enzymes that are responsible for removing acyl modifications from lysine residues. Sirtuins are involved in the formation and proliferation of cancers and are thought to regulate the progression of neurodegenerative diseases. Although sirtuins can be pharmacologically targeted by small molecules, it is not easy to modulate the substrate selectivity of sirtuins despite the chemical diversity of their substrates. Here, we report substrate-specific effects on sirtuin conformation and oligomerization that regulate enzyme deacylase activity. We used fluorescent acyl peptide probes to study substrate interactions with two sirtuin isoforms: SIRT2 and …

Ung2 And Rpa Activity On Ssdna-Dsdna Junctions, Kathy Chen, Sharon Greenwood, Brian P. Weiser

Rowan-Virtua Research Day

Uracil DNA glycosylase, or UNG2, is an enzyme that is involved in DNA repair. Its primary job is to eliminate harmful uracil bases from DNA strands. To do this, the enzyme is assisted by replication protein A (RPA). RPA helps UNG2 in the identification of uracil bases by targeting UNG2 activity near ssDNA-dsDNA junctions (1-3). The results from assays presented here agree with published findings that showed UNG2 is heavily targeted by RPA to uracil bases that are close to ssDNA-dsDNA junctions (for example, uracil located 9 bps from the junction as opposed to 33 bps) (1,2). However, these previous …

Mechanism Of Rare Variant In Acta2, P.Arg149cys, Driving Diverse Vascular Disease, Kaveeta Kaw

Dissertations and Theses (Open Access)

Heterozygous variants in ACTA2 (smooth muscle (SM) α-actin) predispose to thoracic aortic aneurysms and dissections (TAAD) and early-onset coronary artery disease (CAD). The most common ACTA2 mutation is a genetic alteration of arginine 149 to a cysteine, ACTA2 p.Arg149Cys, which accounts for disease in 24% of all ACTA2 mutation carriers.(1) ACTA2 p.Arg149Cys mutation carriers present with either TAAD or CAD but rarely have both diseases. To identify the molecular mechanisms dictating whether an individual with ACTA2 p.Arg149Cys develops TAAD or CAD, CRISPR/Cas9 technology was used to generate the mutant mouse, Acta2^R149C/+, in a C57BL6 background. Acta2^R149C/+ mice …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …