Life Sciences Commons^™

Targeted Repression Of Topa By Crispri Reveals A Critical Function For Balanced Dna Topoisomerase I Activity In The Chlamydia Trachomatis Developmental Cycle, Li Shen, Leiqiong Gao, Abigail R. Swoboda, Scot P. Ouellette

School of Medicine Faculty Publications

Chlamydia trachomatis is an obligate intracellular bacterium that is responsible for the most prevalent bacterial sexually transmitted infection. Changes in DNA topology in this pathogen have been linked to its pathogenicity-associated developmental cycle. Here, evidence is provided that the balanced activity of DNA topoisomerases contributes to controlling Chlamydia developmental processes. Utilizing catalytically inactivated Cas12 (dCas12)-based clustered regularly interspaced short palindromic repeats interference (CRISPRi) technology, we demonstrate targeted knockdown of chromosomal topA transcription in C. trachomatis without detected toxicity of dCas12. Repression of topA impaired the developmental cycle of C. trachomatis mostly through disruption of its differentiation from a replicative form …

Anti-Tick Vaccine Candidate Subolesin Is Important For Blood Feeding And Innate Immune Gene Expression In Soft Ticks, Krittika Nandy, Comfort Tamakloe, Daniel E. Sonenshine, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Subolesin is a conserved molecule in both hard and soft ticks and is considered as an effective candidate molecule for the development of anti-tick vaccine. Previous studies have reported the role of subolesin in blood feeding, reproduction, development, and gene expression in hard ticks. However, studies addressing the role of subolesin in soft ticks are limited. In this study, we report that subolesin is not only important in soft tick Ornithodoros turicata americanus blood feeding but also in the regulation of innate immune gene expression in these ticks. We identified and characterized several putative innate immune genes including Toll, Lysozyme …

Improved Radiation Expression Profiling In Blood By Sequential Application Of Sensitive And Specific Gene Signatures, Eliseos J. Mucaki, Ben C. Shirley, Peter K. Rogan

Biochemistry Publications

Purpose. Combinations of expressed genes can discriminate radiation-exposed from normal control blood samples by machine learning based signatures (with 8 to 20% misclassification rates). These signatures can quantify therapeutically-relevant as well as accidental radiation exposures. The prodromal symptoms of Acute Radiation Syndrome (ARS) overlap those present in Influenza and Dengue Fever infections. Surprisingly, these human radiation signatures misclassified gene expression profiles of virally infected samples as false positive exposures. The present study investigates these and other confounders, and then mitigates their impact on signature accuracy.

Methods. This study investigated recall by previous and novel radiation signatures independently derived …

Random Forest-Integrated Analysis In Ad And Late Brain Transcriptome-Wide Data To Identify Disease-Specific Gene Expression, Xinxing Wu, Chong Peng, Peter T. Nelson, Qiang Cheng

Sanders-Brown Center on Aging Faculty Publications

Alzheimer's disease (AD) is a complex neurodegenerative disorder that affects thinking, memory, and behavior. Limbic-predominant age-related TDP-43 encephalopathy (LATE) is a recently identified common neurodegenerative disease that mimics the clinical symptoms of AD. The development of drugs to prevent or treat these neurodegenerative diseases has been slow, partly because the genes associated with these diseases are incompletely understood. A notable hindrance from data analysis perspective is that, usually, the clinical samples for patients and controls are highly imbalanced, thus rendering it challenging to apply most existing machine learning algorithms to directly analyze such datasets. Meeting this data analysis challenge is …

Effect Of Intrauterine Smoke Exposure On Microrna-15a Expression In Human Lung Development And Subsequent Asthma Risk., Sunita Sharma, Alvin T. Kho, Divya Chhabra, Kathleen Haley, Carrie A. Vyhlidal, R Gaedigk, J Steven Leeder, Kelan G. Tantisira, Benjamin Raby, Scott T. Weiss

Manuscripts, Articles, Book Chapters and Other Papers

Background: In utero smoke (IUS) exposure is associated with asthma susceptibility.

Objective: We sought to test the hypothesis that changes in miRNA expression by IUS exposure during human lung development is associated with asthma susceptibility.

Methods: Gene expression was profiled from 53 IUS unexposed and 51 IUS exposed human fetal lung tissues. We tested for the differential expression of miRNAs across post-conception age and by IUS using linear models with covariate adjustment. We tested the IUS-associated miRNAs for association with their gene expression targets using pair-wise inverse correlation. Using our mouse model, we investigated the persistence of the IUS-associated miRNA …

Expression Of Cytokines And Chemokines As Predictors Of Stroke Outcomes In Acute Ischemic Stroke, Sarah R. Martha, Qiang Cheng, Justin F. Fraser, Liyu Gong, Lisa A. Collier, Stephanie M. Davis, Doug Lukins, Abdulnasser Alhajeri, Stephen Grupke, Keith R. Pennypacker

Institute for Biomedical Informatics Faculty Publications

Introduction: Ischemic stroke remains one of the most debilitating diseases and is the fifth leading cause of death in the US. The ability to predict stroke outcomes within the acute period of stroke would be essential for care planning and rehabilitation. The Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC; clinicaltrials.gov NCT03153683) study collects arterial blood immediately distal and proximal to the intracranial thrombus at the time of mechanical thrombectomy. These blood samples are an innovative resource in evaluating acute gene expression changes at the time of ischemic stroke. The purpose of this study was to identify inflammatory genes and …

Advances In Gene Ontology Utilization Improve Statistical Power Of Annotation Enrichment, Eugene Waverly Hinderer Iii, Robert M. Flight, Rashmi Dubey, James N. Macleod, Hunter N. B. Moseley

Maxwell H. Gluck Equine Research Center Faculty Publications

Gene-annotation enrichment is a common method for utilizing ontology-based annotations in gene and gene-product centric knowledgebases. Effective utilization of these annotations requires inferring semantic linkages by tracing paths through edges in the ontological graph, referred to as relations. However, some relations are semantically problematic with respect to scope, necessitating their omission or modification lest erroneous term mappings occur. To address these issues, we created the Gene Ontology Categorization Suite, or GOcats—a novel tool that organizes the Gene Ontology into subgraphs representing user-defined concepts, while ensuring that all appropriate relations are congruent with respect to scoping semantics. Here, we demonstrate the …

Adipose-Derived Autotaxin Regulates Inflammation And Steatosis Associated With Diet-Induced Obesity, J. Anthony Brandon, Maria Kraemer, Julia Vandra, Suchismita Halder, Margo F. Ubele, Andrew J. Morris, Susan S. Smyth

Gill Heart & Vascular Institute Faculty Publications

Autotaxin (ATX) is a secreted enzyme that generates the bioactive lipid lysophosphatidic acid (LPA). We generated mice with global inducible post-natal inactivation or adipose-specific loss of the Enpp2 gene encoding ATX. The animals are phenotypically unremarkable and exhibit differences in adipocyte size and adipose tissue expression of inflammatory genes after high fat feeding without gross differences in fat distribution or body mass. Surprisingly, both models of Enpp2- deficiency exhibited marked protection from high fat diet-induced hepatic steatosis. This phenotype was not associated with differences in dietary fat absorption but may be accounted for by differences in hepatic expression of …

Differential Expression Of Genes Related To Innate Immune Responses In Ex Vivo Spinal Cord And Cerebellar Slice Cultures Infected With West Nile Virus, Amber M. Paul, Parminder J.S. Vig, Deyin Lu, Ram Kuwar, Maria Lopez, Dobrivoje S. Stokic, A. Arturo Leis, Michael R. Garrett, Fengwei Bai

Publications

West Nile virus (WNV) infection results in a spectrum of neurological symptoms, ranging from a benign fever to severe WNV neuroinvasive disease with high mortality. Many who recover from WNV neuroinvasive infection present with long-term deficits, including weakness, fatigue, and cognitive problems. While neurons are a main target of WNV, other cell types, especially astrocytes, play an important role in promoting WNV-mediated central nervous system (CNS) damage. Conversely, it has been shown that cultured primary astrocytes secrete high levels of interferons (IFNs) immediately after WNV exposure to protect neighboring astrocytes, as well as neurons. However, how intrinsic responses to WNV …

Identification Of Susceptibility Pathways For The Role Of Chromosome 15q25.1 In Modifying Lung Cancer Risk, Xuemei Ji, Yohan Bossé, Maria Teresa Landi, Jiang Gui, Xiangjun Xiao, David Qian, Philippe Joubert Joubert, Maxime Lamontagne, Yafang Li, Ivan Gorlov, Mariella De Biasi, Younghun Han, Olga Gorlova, Rayjean J. Hung, Xifeng Wu, James Mckay, Xuchen Zong, Robert Carreras-Torres, David C. Christiani, Neil Caporaso, Mattias Johansson, Geoffrey Liu, Stig E. Bojesen, Loic Le Marchand, Demetrios Albanes, Heike Bickeböller, Melinda C. Aldrich, William S. Bush, Adonina Tardon, Gad Rennert, Susanne M. Arnold

Markey Cancer Center Faculty Publications

Genome-wide association studies (GWAS) identified the chromosome 15q25.1 locus as a leading susceptibility region for lung cancer. However, the pathogenic pathways, through which susceptibility SNPs within chromosome 15q25.1 affects lung cancer risk, have not been explored. We analyzed three cohorts with GWAS data consisting 42,901 individuals and lung expression quantitative trait loci (eQTL) data on 409 individuals to identify and validate the underlying pathways and to investigate the combined effect of genes from the identified susceptibility pathways. The KEGG neuroactive ligand receptor interaction pathway, two Reactome pathways, and 22 Gene Ontology terms were identified and replicated to be significantly associated …

Downregulation Of Srebp Inhibits Tumor Growth And Initiation By Altering Cellular Metabolism In Colon Cancer, Yang-An Wen, Xiaopeng Xiong, Yekaterina Y. Zaytseva, Dana L. Napier, Emma Vallee, Austin T. Li, Chi Wang, Heidi L. Weiss, B. Mark Evers, Tianyan Gao

Markey Cancer Center Faculty Publications

Sterol regulatory element-binding proteins (SREBPs) belong to a family of transcription factors that regulate the expression of genes required for the synthesis of fatty acids and cholesterol. Three SREBP isoforms, SREBP1a, SREBP1c, and SREBP2, have been identified in mammalian cells. SREBP1a and SREBP1c are derived from a single gene through the use of alternative transcription start sites. Here we investigated the role of SREBP-mediated lipogenesis in regulating tumor growth and initiation in colon cancer. Knockdown of either SREBP1 or SREBP2 decreased levels of fatty acids as a result of decreased expression of SREBP target genes required for lipid biosynthesis in …

Programming Heart Disease: Does Poor Maternal Nutrition Alter Expression Of Cardiac Markers Of Proliferation, Hypertrophy, And Fibrosis In Offspring?, Cathy Chun

Honors Scholar Theses

Maternal malnutrition can affect fetal organogenesis, metabolic processes, and factors involved in developmental regulation. Of the many physiological effects poor maternal nutrition can induce in offspring, one of the most important organs affected is the heart. Cardiovascular disease has been associated with poor maternal diet. It also been suggested that hypertension can originate during impaired intrauterine growth and development. Hypertension can trigger hypertensive heart disease and is associated with numerous heart complications. We hypothesized that poor maternal nutrition would alter critical growth factors associated with normal heart development, specifically, insulin-like growth factor (IGF)-1, IGF-2, transforming growth factor (TGF)β, and connective …

Using Expression Profiling To Understand The Effects Of Chronic Cadmium Exposure On Mcf-7 Breast Cancer Cells, Zelmina Lubovac-Pilav, Daniel M. Borras, Esmeralda Ponce, Maggie Louie

Collected Faculty and Staff Scholarship

Cadmium is a metalloestrogen known to activate the estrogen receptor and promote breast cancer cell growth. Previous studies have implicated cadmium in the development of more malignant tumors; however the molecular mechanisms behind this cadmium-induced malignancy remain elusive. Using clonal cell lines derived from exposing breast cancer cells to cadmium for over 6 months (MCF-7-Cd4, -Cd6, -Cd7, -Cd8 and -Cd12), this study aims to identify gene expression signatures associated with chronic cadmium exposure. Our results demonstrate that prolonged cadmium exposure does not merely result in the deregulation of genes but actually leads to a distinctive expression profile. The genes deregulated …

Chronic Cadmium Exposure Stimulates Sdf-1 Expression In An Erα Dependent Manner, Esmeralda Ponce, Natalie B. Aquino, Maggie Louie

Collected Faculty and Staff Scholarship

Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell …

Characterization Of Brer Interaction With The Bile Response Promoters Breab And Brer In Vibrio Cholerae, Francisca A. Cerda-Maira, Gabriela Kovacikova, Brooke A. Jude, Karen Skorupski, Ronald Taylor

Dartmouth Scholarship

The Vibrio cholerae BreR protein is a transcriptional repressor of the breAB efflux system operon, which encodes proteins involved in bile resistance. In a previous study (F. A. Cerda-Maira, C. S. Ringelberg, and R. K. Taylor, J. Bacteriol. 190:7441-7452, 2008), we used gel mobility shift assays to determine that BreR binds at two independent binding sites at the breAB promoter and a single site at its own promoter. Here it is shown, by DNase I footprinting and site-directed mutagenesis, that BreR is able to bind at a distal and a proximal site in the breAB promoter. However, only one of …

Trefoil Factor 2 (Tff2) Deficiency In Murine Digestive Tract Influences The Immune System, M. Baus- Loncar, J. Schmid, El-Nasir Lalani, I. Rosewell, R. A. Goodlad, H. G.W. Stamp, N. Blin, T. Kayademir

Department of Pathology and Laboratory Medicine

Background & Aims:

The gastrointestinal trefoil factor family (TFF1, TFF2, TFF3) peptides are considered to play an important role in maintaining the integrity of the mucosa. The physiological role of TFF2 in the protection of the GI tract was investigated in TFF2 deficiency.

Methods:

TFF2-/- mice were generated and differential expression of various genes was assessed by using a mouse expression microarray, quantitative real time PCR, Northern blots or immunohistochemistry.

Results:

On an mRNA level we found 128 differentially expressed genes. We observed modulation of a number of crucial genes involved in innate and adaptive immunity in the TFF2-/- mice. …

Induction Of Integral Membrane Pam Expression In Att-20 Cells Alters The Storage And Trafficking Of Pomc And Pc1, Giuseppe D. Ciccotosto, Martin R. Schiller, Betty A. Eipper, Richard E. Mains

Life Sciences Faculty Research

Peptidylglycine alpha-amidating monooxygenase (PAM) is an essential enzyme that catalyzes the COOH-terminal amidation of many neuroendocrine peptides. The bifunctional PAM protein contains an NH2-terminal monooxygenase (PHM) domain followed by a lyase (PAL) domain and a transmembrane domain. The cytosolic tail of PAM interacts with proteins that can affect cytoskeletal organization. A reverse tetracycline-regulated inducible expression system was used to construct an AtT-20 corticotrope cell line capable of inducible PAM-1 expression. Upon induction, cells displayed a time- and dose-dependent increase in enzyme activity, PAM mRNA, and protein. Induction of increased PAM-1 expression produced graded changes in PAM-1 metabolism. Increased expression of …