Biochemistry, Biophysics, and Structural Biology Commons^™

Using The Behaviour Change Wheel Program Planning Model To Design Games For Health: Development Study, Michael C Robertson, Tom Baranowski, Debbe Thompson, Karen M Basen-Engquist, Maria Chang Swartz, Elizabeth J Lyons

Faculty, Staff and Students Publications

BACKGROUND: Games for health are a promising approach to health promotion. Their success depends on achieving both experiential (game) and instrumental (health) objectives. There is little to guide game for health (G4H) designers in integrating the science of behavior change with the art of game design.

OBJECTIVE: The aim of this study is to extend the Behaviour Change Wheel program planning model to develop Challenges for Healthy Aging: Leveraging Limits for Engaging Networked Game-Based Exercise (CHALLENGE), a G4H centered on increasing physical activity in insufficiently active older women.

METHODS: We present and apply the G4H Mechanics, Experiences, and Change (MECHA) …

Differentiating The Mechanistic Role And Chemotherapeutic Potential Of Src And Podoplanin In Oncogenic Transformation, Edward P. Retzbach

Graduate School of Biomedical Sciences Theses and Dissertations

There were an estimated 20 million new cancer cases worldwide in 2020, resulting in nearly 1000 deaths per hour [1]. Oral cancer exemplifies the difficulties of treating cancer patients. The first line for oral cancer treatment is surgery and radiation that can lead to patient disfigurement and decreased quality of life in cancer survivors [2-4]. Though there have been many developments in chemotherapy in the last 30 years, the 50% mortality rate associated with oral cancer has not changed [4, 5]. Longitudinal studies that track survival rates in oral cancer patients demonstrate a 3-fold reduction in patient deaths when patients …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Predicted Vitamin D Status And Colorectal Cancer Incidence In The Black Women's Health Study, Lauren E Barber, Kimberly A Bertrand, Jessica L Petrick, Hanna Gerlovin, Laura F White, Lucile L Adams-Campbell, Lynn Rosenberg, Hemant K Roy, Julie R Palmer

Faculty, Staff and Students Publications

BACKGROUND: Observational studies, mostly among White populations, suggest that low vitamin D levels increase colorectal cancer risk. African Americans, who are disproportionately burdened by colorectal cancer, often have lower vitamin D levels compared with other populations.

METHODS: We assessed predicted vitamin D score in relation to colorectal cancer among 49,534 participants in the Black Women's Health Study, a cohort of African American women followed from 1995 to 2017 through biennial questionnaires. We derived predicted vitamin D scores at each questionnaire cycle for all participants using a previously validated prediction model based on actual 25-hydroxyvitamin D values from a subset of …

Associations Of High-Sensitivity Troponin And Natriuretic Peptide Levels With Outcomes After Intensive Blood Pressure Lowering: Findings From The Sprint Randomized Clinical Trial, Jarett D Berry, Vijay Nambi, Walter T Ambrosius, Haiying Chen, Anthony A Killeen, Addison Taylor, Robert D Toto, Elsayed Z Soliman, John W Mcevoy, Ambarish Pandey, Parag H Joshi, Stefan Blankenberg, Dalane W Kitzman, Christie M Ballantyne, James A De Lemos

Faculty, Staff and Students Publications

IMPORTANCE: Elevated high-sensitivity cardiac troponin T (hscTnT) and N-terminal pro-B-type natriuretic peptide (NTproBNP) levels are associated with risk of heart failure (HF) and mortality among individuals in the general population. However, it is unknown if this risk is modifiable.

OBJECTIVE: To test the hypothesis that elevated hscTnT and NTproBNP levels would identify individuals with the greatest risk for mortality and HF and the largest benefit associated with intensive systolic blood pressure (SBP) lowering.

DESIGN, SETTING, AND PARTICIPANTS: This is a nonprespecified post hoc analysis of the multicenter, prospective, randomized clinical Systolic Blood Pressure Intervention Trial (SPRINT), conducted from October 20, …

Genetic Testing In Ambulatory Cardiology Clinics Reveals High Rate Of Findings With Clinical Management Implications, David R Murdock, Eric Venner, Donna M Muzny, Ginger A Metcalf, Mullai Murugan, Trevor D Hadley, Varuna Chander, Paul S De Vries, Xiaoming Jia, Aliza Hussain, Ali M Agha, Aniko Sabo, Shoudong Li, Qingchang Meng, Jianhong Hu, Xia Tian, Michelle Cohen, Victoria Yi, Christie L Kovar, Marie-Claude Gingras, Viktoriya Korchina, Chad Howard, Daniel L Riconda, Stacey Pereira, Hadley S Smith, Zohra A Huda, Alexandria Buentello, Patricia R Marino, Lee Leiber, Ashok Balasubramanyam, Christopher I Amos, Andrew B Civitello, Mihail G Chelu, Ronald Maag, Amy L Mcguire, Eric Boerwinkle, Xander H T Wehrens, Christie M Ballantyne, Richard A Gibbs

Faculty, Staff and Students Publications

PURPOSE: Cardiovascular disease (CVD) is the leading cause of death in adults in the United States, yet the benefits of genetic testing are not universally accepted.

METHODS: We developed the "HeartCare" panel of genes associated with CVD, evaluating high-penetrance Mendelian conditions, coronary artery disease (CAD) polygenic risk, LPA gene polymorphisms, and specific pharmacogenetic (PGx) variants. We enrolled 709 individuals from cardiology clinics at Baylor College of Medicine, and samples were analyzed in a CAP/CLIA-certified laboratory. Results were returned to the ordering physician and uploaded to the electronic medical record.

RESULTS: Notably, 32% of patients had a genetic finding with clinical …

Effects Of Localized Oxygen Production By Electrolysis On The First-Generation Glucose Sensor Response, Nandita Halder

Graduate Theses and Dissertations

Glucose sensors are very important for detecting blood glucose both in vitro and in vivo. First-generation glucose biosensors were based on the glucose oxidase (GOx) enzyme using molecular oxygen as the electron acceptor and therefore oxygen dependent. Unfortunately for in-vivo work, oxygen in the body is variable and limited. Alternative approaches to overcome the oxygen dependency came with their own limitations. The widely used and commercially available ex-vivo glucose test strip uses a mediator in place of oxygen to free it from oxygen dependency. The mediator-based technology, in most cases cannot be transferred to in vivo applications due to the …

The Landscape Of Renal Replacement Therapy In Veterans Affairs Medical Center Intensive Care Units, Chandan Vangala, Maulin Shah, Natasha N Dave, Layth Al Attar, Sankar D Navaneethan, Venkat Ramanathan, Susan Crowley, Wolfgang C Winkelmayer

Faculty, Staff and Students Publications

BACKGROUND: Outpatient dialysis is standardized with several evidence-based measures of adequacy and quality that providers aim to meet while providing treatment. By contrast, in the intensive care unit (ICU) there are different types of prolonged and continuous renal replacement therapies (PIRRT and CRRT, respectively) with varied strategies for addressing patient care and a dearth of nationally accepted quality parameters. To eventually describe appropriate quality measures for ICU-related renal replacement therapy (RRT), we first aimed to capture the variety and prevalence of basic strategies and equipment utilized in the ICUs of Veteran Affairs (VA) medical facilities with inpatient hemodialysis capabilities.

METHODS: …

Transient Ascaris Suum Larval Migration Induces Intractable Chronic Pulmonary Disease And Anemia In Mice, Yifan Wu, Evan Li, Morgan Knight, Grace Adeniyi-Ipadeola, Li-Zhen Song, Alan R Burns, Ana Clara Gazzinelli-Guimaraes, Ricardo Fujiwara, Maria Elena Bottazzi, Jill E Weatherhead

Faculty, Staff and Students Publications

Ascariasis is one of the most common infections in the world and associated with significant global morbidity. Ascaris larval migration through the host's lungs is essential for larval development but leads to an exaggerated type-2 host immune response manifesting clinically as acute allergic airway disease. However, whether Ascaris larval migration can subsequently lead to chronic lung diseases remains unknown. Here, we demonstrate that a single episode of Ascaris larval migration through the host lungs induces a chronic pulmonary syndrome of type-2 inflammatory pathology and emphysema accompanied by pulmonary hemorrhage and chronic anemia in a mouse model. Our results reveal that …

Case Report: Molecular Diagnosis Of Cystoisospora Belli In A Severely Immunocompromised Patient With Hiv And Kaposi Sarcoma, Roumen Borilov Iordanov, Lauren M Leining, Meng Wu, Galant Chan, Andrew R Dinardo, Rojelio Mejia

Faculty, Staff and Students Publications

Diarrhea in an immunocompromised patient has a broad infectious differential. Diagnosis is difficult despite advances in diagnostic modalities. We report a case of a 45-year-old Nigerian woman who immigrated to the United States 2 years ago. She presented to the hospital with gastrointestinal bleeding, newly diagnosed HIV, and disseminated Kaposi sarcoma. During hospitalization, the patient had an onset of watery diarrhea and high eosinophilia. Subsequent stool analysis using multi-parallel real-time quantitative polymerase chain reaction for 13 parasites was positive for Cystoisospora belli. The patient was treated with trimethoprim-sulfamethoxazole, but had relapsed disease when her antibiotics were stopped prematurely. After restarting …

Hematopoiesis Under Telomere Attrition At The Single-Cell Resolution, Natthakan Thongon, Feiyang Ma, Andrea Santoni, Matteo Marchesini, Elena Fiorini, Ashley Rose, Vera Adema, Irene Ganan-Gomez, Emma M Groarke, Fernanda Gutierrez-Rodrigues, Shuaitong Chen, Pamela Lockyer, Sarah Schneider, Carlos Bueso-Ramos, Guillermo Montalban-Bravo, Caleb A Class, Kelly A Soltysiak, Matteo Pellegrini, Ergun Sahin, Alison A Bertuch, Courtney D Dinardo, Guillermo Garcia-Manero, Neal S Young, Karen Dwyer, Simona Colla

Faculty, Staff and Students Publications

The molecular mechanisms that drive hematopoietic stem cell functional decline under conditions of telomere shortening are not completely understood. In light of recent advances in single-cell technologies, we sought to redefine the transcriptional and epigenetic landscape of mouse and human hematopoietic stem cells under telomere attrition, as induced by pathogenic germline variants in telomerase complex genes. Here, we show that telomere attrition maintains hematopoietic stem cells under persistent metabolic activation and differentiation towards the megakaryocytic lineage through the cell-intrinsic upregulation of the innate immune signaling response, which directly compromises hematopoietic stem cells' self-renewal capabilities and eventually leads to their exhaustion. …

Chemical And Biological Characterization Of The Anticancer Potency Of Salvia Fruticosa In A Model Of Human Malignant Melanoma, Sotiris Kyriakou, Venetia Tragkola, Michael Plioukas, Ioannis Anestopoulos, Paschalina S. Chatzopoulou, Eirini Sarrou, Dimitrios T. Trafalis, Maria V. Deligiorgi, Rodrigo Franco, Aglaia Pappa, Mihalis I. Panayiotidi

School of Veterinary and Biomedical Sciences: Faculty Publications

Malignant melanoma is one of the most aggressive types of skin cancer with an increasing incidence worldwide. Thus, the development of innovative therapeutic approaches is of great importance. Salvia fruticosa (SF) is known for its anticancer properties and in this context, we aimed to investigate its potential anti-melanoma activity in an in vitro model of human malignant melanoma. Cytotoxicity was assessed through a colorimetric-based sulforhodamine-B (SRB) assay in primary malignant melanoma (A375), non-malignant melanoma epidermoid carcinoma (A431) and non-tumorigenic melanocyte neighbouring keratinocyte (HaCaT) cells. Among eight (8) different fractions of S. fruticosa extracts (SF1-SF8) tested, SF3 was found to possess …

Mt10-Cvb3 Vaccine Virus Protects Against Cvb4 Infection By Inducing Cross-Reactive, Antigen-Specific Immune Responses, Ninaad Lasrado, Rajkumar Arumugam, Mahima T. Rasquinha, Meghna Sur, David Steffen, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Group B coxsackieviruses (CVB) containing six serotypes, B1–B6, affect various organs, and multiple serotypes can induce similar diseases such as myocarditis and pancreatitis. Yet, no vaccines are currently available to prevent these infections. Translationally, the derivation of vaccines that offer protection against multiple serotypes is highly desired. In that direction, we recently reported the generation of an attenuated strain of CVB3, termed Mt10, which completely protects against both myocarditis and pancreatitis induced by the homologous wild-type CVB3 strain. Here, we report that the Mt10 vaccine can induce cross-protection against multiple CVB serotypes as demonstrated with CVB4. We note that the …

Ultrafiltration Rate And Incident Atrial Fibrillation Among Older Individuals Initiating Hemodialysis, Jennifer E Flythe, Sai Liu, Maria E Montez-Rath, Wolfgang C Winkelmayer, Tara I Chang

Faculty, Staff and Students Publications

BACKGROUND: Higher ultrafiltration (UF) rates are associated with numerous adverse cardiovascular outcomes among individuals receiving maintenance hemodialysis. We undertook this study to investigate the association of UF rate and incident atrial fibrillation in a large, nationally representative US cohort of incident, older hemodialysis patients.

METHODS: We used the US Renal Data System linked to the records of a large dialysis provider to identify individuals ≥67 years of age initiating hemodialysis between January 2006 and December 2011. We applied an extended Cox model as a function of a time-varying exposure to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) …

Contact Normalization And The Role Of Maackia Amurensis Seed Lectin As A Novel Chemotherapeutic And Antiviral Agent, Stephanie A. Sheehan

Graduate School of Biomedical Sciences Theses and Dissertations

Cells communicate with each other to coordinate tissue function and homeostasis. Diseases including cancer, arthritis, and acute respiratory disease syndrome (ARDS) require a breakdown in this intercellular communication. For example, cancer progression is suppressed by junctional communication between nontransformed and transformed cells. This process is called contact normalization. Junctional communication must be disrupted to enable transformed cells to grow into malignancies. However, the junctions and mechanisms by which nontransformed cells normalize cell behavior have not been clearly defined. My project aimed to identify junctions and elucidate mechanisms underlying contact normalization. We discovered that cadherins, specifically N-cadherin, form junctions that enable …

Ckb Inhibits Epithelial-Mesenchymal Transition And Prostate Cancer Progression By Sequestering And Inhibiting Akt Activation, Zheng Wang, Mohit Hulsurkar, Lijuan Zhuo, Jinbang Xu, Han Yang, Samira Naderinezhad, Lin Wang, Guoliang Zhang, Nanping Ai, Linna Li, Jeffrey T Chang, Songlin Zhang, Ladan Fazli, Chad J Creighton, Fang Bai, Michael M Ittmann, Martin E Gleave, Wenliang Li

Faculty, Staff and Students Publications

Epithelial-mesenchymal transition (EMT) contributes to tumor invasion, metastasis and drug resistance. AKT activation is key in a number of cellular processes. While many positive regulators for either EMT or AKT activation have been reported, few negative regulators are established. Through kinase cDNA screen, we identified brain-type creatine kinase (CKB or BCK) as a potent suppressor for both. As a ubiquitously expressed kinase in normal tissues, CKB is significantly downregulated in several solid cancer types. Lower CKB expression is significantly associated with worse prognosis. Phenotypically, CKB overexpression suppresses, while its silencing promotes, EMT and cell migration, xenograft tumor growth and metastasis …

Patient Characteristics And Outcomes Of Type 2 Myocardial Infarction During Heart Failure Hospitalizations In The United States, Salik Nazir, Abdul Mannan Khan Minhas, Ishan S Kamat, Robert W Ariss, George V Moukarbel, Juan Carlos Plana Gomez, Savitri Fedson, Ajith Nair, Biykem Bozkurt, Hani Jneid

Faculty, Staff and Students Publications

BACKGROUND: Type 2 myocardial infarction (MI) is increasingly diagnosed in patients with heart failure (HF). A paucity of data exists pertinent to the contemporary prevalence and impact of type 2 MI in patients with HF. We studied the patient profiles and the prognostic impact of type 2 MI on outcomes of HF hospitalizations.

METHODS: The Nationwide Readmission Database 2018 was queried for patients with HF hospitalizations with and without type 2 MI. Baseline characteristics, inpatient outcomes, and 30-day all-cause readmissions between both cohorts were compared.

RESULTS: Of 1,072,674 primary HF hospitalizations included in the study, 28,813 (2.7%) had type 2 …

Mortality, Kidney Failure, And Hospitalization Among Medicare Beneficiaries With Ckd And Pulmonary Hypertension, Sankar D Navaneethan, Carl P Walther, L Parker Gregg, Shweta Bansal, Wolfgang C Winkelmayer, Vijay Nambi, Jingbo Niu

Faculty, Staff and Students Publications

RATIONALE & OBJECTIVE: Pulmonary hypertension (PH) is highly prevalent among patients with chronic kidney disease (CKD) not requiring kidney replacement therapy. We studied the associations of PH with mortality, kidney failure, as well as cardiovascular (CV) and non-CV hospitalization among Medicare beneficiaries with a CKD diagnosis.

STUDY DESIGN: Retrospective, observational study using a matched cohort design.

SETTING & PARTICIPANTS: Patients with PH (based on 2 claims within 2 years) and patients without PH matched on CKD stage from the Medicare 5% CKD sample (1996-2016).

PREDICTOR: Presence of pulmonary hypertension.

OUTCOME: Mortality, kidney failure, and all-cause, CV, and non-CV hospitalization.

ANALYTICAL …

Untargeted Lipidomics Of Non-Small Cell Lung Carcinoma Demonstrates Differentially Abundant Lipid Classes In Cancer Vs. Non-Cancer Tissue, Joshua M. Mitchell, Robert M. Flight, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Lung cancer remains the leading cause of cancer death worldwide and non-small cell lung carcinoma (NSCLC) represents 85% of newly diagnosed lung cancers. In this study, we utilized our untargeted assignment tool Small Molecule Isotope Resolved Formula Enumerator (SMIRFE) and ultra-high-resolution Fourier transform mass spectrometry to examine lipid profile differences between paired cancerous and non-cancerous lung tissue samples from 86 patients with suspected stage I or IIA primary NSCLC. Correlation and co-occurrence analysis revealed significant lipid profile differences between cancer and non-cancer samples. Further analysis of machine-learned lipid categories for the differentially abundant molecular formulas identified a high abundance sterol, …

Physiological Roles Of Mammalian Transmembrane Adenylyl Cyclase Isoforms, Katrina F. Ostrom, Justin E. Lavigne, Tarsis F. Brust, Roland Seifert, Carmen Dessauer, Val J. Watts, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors. The transmembrane ACs display varying expression patterns across tissues, giving potential for them having a wide array of physiologic roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gα_s so it was long assumed that all ACs are activated by Gα_s-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form …

Super-Resolution Microscopy Reveals Photoreceptor-Specific Subciliary Location And Function Of Ciliopathy-Associated Protein Cep290, Valencia L Potter, Abigail R Moye, Michael A Robichaux, Theodore G Wensel

Faculty, Staff and Students Publications

Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multiorgan ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used super-resolution fluorescence microscopy and electron microscopy to localize CEP290 in the CC and in the primary cilia of cultured cells with subdiffraction resolution and to determine effects of CEP290 deficiency in 3 mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout …

Inheritance Of A Mutation Causing Neuropathy With Splayed Forelimbs In Jersey Cattle, A. Al-Khudhair, D. J. Null, J. B. Cole, C. W. Wolfe, David J. Steffen, P. M. Vanraden

School of Veterinary and Biomedical Sciences: Faculty Publications

A new undesirable genetic factor, neuropathy with splayed forelimbs (JNS), has been identified recently in the Jersey breed. Calves affected with JNS are unable to stand on splayed forelimbs that exhibit significant extensor rigidity and excessive lateral abduction at birth. Affected calves generally are alert at birth but exhibit neurologic symptoms, including spasticity of head and neck and convulsive behavior. Other symptoms reported include dislocated shoulders, congenital craniofacial anomalies, and degenerative myelopathy. Inheritance of an undesirable genetic factor was determined from a study of 16 affected calves reported by Jersey breeders across the United States. All of their pedigrees traced …

Simultaneous Monitoring Cytoplasmic Calcium Ion And Cell Surface Phosphatidylserine In The Necrotic Touch Neurons Of Caenorhabditis Elegans, Yoshitaka Furuta, Zheng Zhou

Faculty, Staff and Students Publications

Calcium ions trigger many cellular events, including the release of neurotransmitters at the synaptic terminal and excitotoxic cell death. Recently, we have discovered that a transient increase in the level of cytoplasmic Ca2+ triggers the exposure of phosphatidylserine (PS) on the surfaces of necrotic cells in the nematode Caenorhabditis elegans. PS serves as an “eat me” signal that attracts engulfing cells to engulf and degrade necrotic cells. During the above study, we developed a microscopic imaging protocol for real-time monitoring the levels of cytoplasmic Ca2+ and cell surface PS in Caenorhabditis elegans touch neurons. Previously, Ca2+ dynamics was monitored …

Norovirus Protease Structure And Antivirals Development, Boyang Zhao, Liya Hu, Yongcheng Song, Ketki Patil, Sasirekha Ramani, Robert L Atmar, Mary K Estes, B V Venkataram Prasad

Faculty, Staff and Students Publications

Human norovirus (HuNoV) infection is a global health and economic burden. Currently, there are no licensed HuNoV vaccines or antiviral drugs available. The protease encoded by the HuNoV genome plays a critical role in virus replication by cleaving the polyprotein and is an excellent target for developing small-molecule inhibitors. The current strategy for developing HuNoV protease inhibitors is by targeting the enzyme's active site and designing inhibitors that bind to the substrate-binding pockets located near the active site. However, subtle differential conformational flexibility in response to the different substrates in the polyprotein and structural differences in the active site and …

The Novel Orfv Protein Orfv113 Activates Lpa-P38 Signaling, Sushil Khatiwad, Gustavo Delho, Sabal Chaulagai, Daniel L. Rock

School of Veterinary and Biomedical Sciences: Faculty Publications

Viruses have evolved mechanisms to subvert critical cellular signaling pathways that regulate a wide range of cellular functions, including cell differentiation, proliferation and chemotaxis, and innate immune responses. Here, we describe a novel ORFV protein, ORFV113, that interacts with the G protein-coupled receptor Lysophosphatidic acid receptor 1 (LPA₁). Consistent with its interaction with LPA₁, ORFV113 enhances p38 kinase phosphorylation in ORFV infected cells in vitro and in vivo, and in cells transiently expressing ORFV113 or treated with soluble ORFV113. Infection of cells with virus lacking ORFV113 (OVIA82Δ113) significantly decreased p38 phosphorylation and viral plaque size. …

Alterations To The Brain Following Traumatic Brain Injury, Jacqueline Mader

Honors Projects

Traumatic brain injuries (TBIs) have been labeled as a modern-day epidemic, increasing exponentially with the advancement of technology and society. Gaining a better understanding of the cognitive paths, including the chemical and electrical signals of the brain, neural correlates, and possible interventions for TBI patients allows for the best possible outcome for every patient, and allows for the further advancement of care. By revising and reassessing the ways in which TBIs are categorized and described the prognosis for recovery paints a more realistic view for each individual patient case. The symptoms and impairments that may occur post-injury can be monitored …

Cellular Regeneration As A Potential Strategy To Treat Cardiac Conduction Disorders, Satadru K Lahiri, Mohit M Hulsurkar, Xander Ht Wehrens

Faculty, Staff and Students Publications

Loss of atrioventricular conduction system (AVCS) cells due to either inherited or acquired deficits leads to conduction diseases, which can deteriorate into fatal cardiac arrhythmias and sudden death. In this issue of the JCI, Wang et al. constructed a mouse model of atrioventricular block (AVB) by inducing AVCS cell-specific injury using the Cx30.2 enhancer to drive expression of diphtheria toxin fragment A. AVCS cell ablation in adult mice led to irreversible AVB. jkjkIn contrast, AVCS cell injury in neonatal mice was followed by spontaneous recovery in a subset of mice, revealing a limited postnatal time window during which the regeneration …

Supercoiling And Looping Promote Dna Base Accessibility And Coordination Among Distant Sites, Jonathan M Fogg, Allison K Judge, Erik Stricker, Hilda L Chan, Lynn Zechiedrich

Faculty, Staff and Students Publications

DNA in cells is supercoiled and constrained into loops and this supercoiling and looping influence every aspect of DNA activity. We show here that negative supercoiling transmits mechanical stress along the DNA backbone to disrupt base pairing at specific distant sites. Cooperativity among distant sites localizes certain sequences to superhelical apices. Base pair disruption allows sharp bending at superhelical apices, which facilitates DNA writhing to relieve torsional strain. The coupling of these processes may help prevent extensive denaturation associated with genomic instability. Our results provide a model for how DNA can form short loops, which are required for many essential …

Determining Effective Drug Concentrations For Selection And Counterselection Genetics In Drosophila Melanogaster, Nick Matinyan, Yezabel Gonzalez, Herman A Dierick, Koen J T Venken

Faculty, Staff and Students Publications

We recently integrated into fly genetics a set of four selection and two counterselection markers and their corresponding drugs that can be used individually or in combination. These markers eliminate the need to visually screen progeny. Before using these markers in new genetic backgrounds, effective selection/counterselection concentrations should be established for each marker/drug combination. This protocol describes how to set up, perform, and analyze a drug titration curve to determine the effective selection/counterselection drug concentrations for their corresponding markers. For complete details on the use and execution of this protocol, please refer to Matinyan et al., 2021.

Multiplexed Drug-Based Selection And Counterselection Genetic Manipulations In Drosophila, Nick Matinyan, Mansi S Karkhanis, Yezabel Gonzalez, Antrix Jain, Alexander Saltzman, Anna Malovannaya, Alejandro Sarrion-Perdigones, Herman A Dierick, Koen J T Venken

Faculty, Staff and Students Publications

The power of Drosophila melanogaster as a model system relies on tractable germline genetic manipulations. Despite Drosophila's expansive genetics toolbox, such manipulations are still accomplished one change at a time and depend predominantly on phenotypic screening. We describe a drug-based genetic platform consisting of four selection and two counterselection markers, eliminating the need to screen for modified progeny. These markers work reliably individually or in combination to produce specific genetic outcomes. We demonstrate three example applications of multiplexed drug-based genetics by generating (1) transgenic animals, expressing both components of binary overexpression systems in a single transgenesis step; (2) dual selectable …