Biochemistry, Biophysics, and Structural Biology Commons^™

Loss Of Speg Inhibitory Phosphorylation Of Ryanodine Receptor Type-2 Promotes Atrial Fibrillation, Hannah M Campbell, Ann P Quick, Issam Abu-Taha, David Y Chiang, Carlos F Kramm, Tarah A Word, Sören Brandenburg, Mohit Hulsurkar, Katherina M Alsina, Hui-Bin Liu, Brian Martin, Dennis Uhlenkamp, Oliver M Moore, Satadru K Lahiri, Eleonora Corradini, Markus Kamler, Albert J R Heck, Stephan E Lehnart, Dobromir Dobrev, Xander H T Wehrens

Faculty, Staff and Students Publications

BACKGROUND: Enhanced diastolic calcium (Ca

METHODS: Western blotting was performed with right atrial biopsies from patients with paroxysmal AF. SPEG atrial knockout mice were generated using adeno-associated virus 9. In mice, AF inducibility was determined using intracardiac programmed electric stimulation, and diastolic Ca

RESULTS: Western blotting revealed decreased SPEG protein levels in atrial biopsies from patients with paroxysmal AF in comparison with patients in sinus rhythm. SPEG atrial-specific knockout mice exhibited increased susceptibility to pacing-induced AF by programmed electric stimulation and enhanced Ca

CONCLUSIONS: Unlike other kinases (PKA, CaMKII) that increase RyR2 activity, SPEG phosphorylation reduces RyR2-mediated sarcoplasmic reticulum Ca

Atom Identifiers Generated By A Neighborhood-Specific Graph Coloring Method Enable Compound Harmonization Across Metabolic Databases, Huan Jin, Joshua M. Mitchell, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Metabolic flux analysis requires both a reliable metabolic model and reliable metabolic profiles in characterizing metabolic reprogramming. Advances in analytic methodologies enable production of high-quality metabolomics datasets capturing isotopic flux. However, useful metabolic models can be difficult to derive due to the lack of relatively complete atom-resolved metabolic networks for a variety of organisms, including human. Here, we developed a neighborhood-specific graph coloring method that creates unique identifiers for each atom in a compound facilitating construction of an atom-resolved metabolic network. What is more, this method is guaranteed to generate the same identifier for symmetric atoms, enabling automatic identification of …

Estimating Partial Body Ionizing Radiation Exposure By Automated Cytogenetic Biodosimetry, Peter Rogan

Biochemistry Publications

Purpose: Inhomogeneous exposures to ionizing radiation can be detected and quantified with the Dicentric Chromosome Assay (DCA) of metaphase cells. Complete automation of interpretation of the DCA for whole body irradiation has significantly improved throughput without compromising accuracy, however low levels of residual false positive dicentric chromosomes (DCs) have confounded its application for partial body exposure determination.

Materials and Methods: We describe a method of estimating and correcting for false positive DCs in digitally processed images of metaphase cells. Nearly all DCs detected in unirradiated calibration samples are introduced by digital image processing. DC frequencies of irradiated calibration …

Structural Insights Of Transcriptionally Active, Full-Length Androgen Receptor Coactivator Complexes, Xinzhe Yu, Ping Yi, Ross A Hamilton, Hong Shen, Muyuan Chen, Charles E Foulds, Michael A Mancini, Steven J Ludtke, Zhao Wang, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptors activate gene transcription by recruiting coactivators to initiate transcription of their target genes. For most nuclear receptors, the ligand-dependent activation function domain-2 (AF-2) is a primary contributor to the nuclear receptor (NR) transcriptional activity. In contrast to other steroid receptors, such as ERα, the activation function of androgen receptor (AR) is largely dependent on its ligand-independent AF-1 located in its N-terminal domain (NTD). It remains unclear why AR utilizes a different AF domain from other receptors despite that NRs share similar domain organizations. Here, we present cryoelectron microscopy (cryo-EM) structures of DNA-bound full-length AR and its complex structure …

Characterization Of Retinal Biomechanical Properties Using Brillouin Microscopy, Yogeshwari S Ambekar, Manmohan Singh, Giuliano Scarcelli, Elda M Rueda, Benjamin M Hall, Ross A Poché, Kirill V Larin

Faculty, Staff and Students Publications

SIGNIFICANCE: The retina is critical for vision, and several diseases may alter its biomechanical properties. However, assessing the biomechanical properties of the retina nondestructively is a challenge due to its fragile nature and location within the eye globe. Advancements in Brillouin spectroscopy have provided the means for nondestructive investigations of retina biomechanical properties.

AIM: We assessed the biomechanical properties of mouse retinas using Brillouin microscopy noninvasively and showed the potential of Brillouin microscopy to differentiate the type and layers of retinas based on stiffness.

APPROACH: We used Brillouin microscopy to quantify stiffness of fresh and paraformaldehyde (PFA)-fixed retinas. As further …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Structure And Mechanism Of A Unique Diiron Center In Mammalian Stearoyl-Coa Desaturase, Jiemin Shen, Gang Wu, Ah-Lim Tsai, Ming Zhou

Faculty, Staff and Students Publications

Stearoyl-CoA desaturase 1 (SCD1) is a membrane-embedded metalloenzyme that catalyzes formation of a double-bond on a saturated acyl-CoA. SCD1 has a diiron center and its proper function requires an electron transport chain composed of NADH (or NADPH), cytochrome b5 reductase (b5R), and cytochrome b5 (cyt b5). Since SCD1 is a key regulator in fat metabolism and is required for survival of cancer cells, there is intense interest in targeting SCD1 for various metabolic diseases and cancers. Crystal structures of human and mouse SCD1 were reported recently, however, both proteins have two zinc ions instead of two iron ions in the …

The Ubiquitin Ligase Cullin-1 Associates With Chromatin And Regulates Transcription Of Specific C-Myc Target Genes, Melanie A Sweeney, Polina Iakova, Laure Maneix, Fu-Yuan Shih, Hannah E Cho, Ergun Sahin, Andre Catic

Faculty, Staff and Students Publications

Transcription is regulated through a dynamic interplay of DNA-associated proteins, and the composition of gene-regulatory complexes is subject to continuous adjustments. Protein alterations include post-translational modifications and elimination of individual polypeptides. Spatially and temporally controlled protein removal is, therefore, essential for gene regulation and accounts for the short half-life of many transcription factors. The ubiquitin-proteasome system is responsible for site- and target-specific ubiquitination and protein degradation. Specificity of ubiquitination is conferred by ubiquitin ligases. Cullin-RING complexes, the largest family of ligases, require multi-unit assembly around one of seven cullin proteins. To investigate the direct role of cullins in ubiquitination of …

Modulation Of Lymphocyte Potassium Channel Kv13 By Membrane-Penetrating, Joint-Targeting Immunomodulatory Plant Defensin, Seow Theng Ong, Saumya Bajaj, Mark R Tanner, Shih Chieh Chang, Bankala Krishnarjuna, Xuan Rui Ng, Rodrigo A V Morales, Ming Wei Chen, Dahai Luo, Dharmeshkumar Patel, Sabina Yasmin, Jeremy Jun Heng Ng, Zhong Zhuang, Hai M Nguyen, Abbas El Sahili, Julien Lescar, Rahul Patil, Susan A Charman, Edward G Robins, Julian L Goggi, Peng Wen Tan, Pragalath Sadasivam, Boominathan Ramasamy, Siddana V Hartimath, Vikas Dhawan, Janna Bednenko, Paul Colussi, Heike Wulff, Michael W Pennington, Serdar Kuyucak, Raymond S Norton, Christine Beeton, K George Chandy

Faculty, Staff and Students Publications

We describe a cysteine-rich, membrane-penetrating, joint-targeting, and remarkably stable peptide, EgK5, that modulates voltage-gated KV1.3 potassium channels in T lymphocytes by a distinctive mechanism. EgK5 enters plasma membranes and binds to KV1.3, causing current run-down by a phosphatidylinositol 4,5-bisphosphate-dependent mechanism. EgK5 exhibits selectivity for KV1.3 over other channels, receptors, transporters, and enzymes. EgK5 suppresses antigen-triggered proliferation of effector memory T cells, a subset enriched among pathogenic autoreactive T cells in autoimmune disease. PET-CT imaging with 18F-labeled EgK5 shows accumulation of the peptide in large and small joints of rodents. In keeping with its arthrotropism, EgK5 treats disease in a rat …

Metabolism Of Jq1, An Inhibitor Of Bromodomain And Extra Terminal Bromodomain Proteins, In Human And Mouse Liver Microsomes†, Feng Li, Kevin R Mackenzie, Prashi Jain, Conrad Santini, Damian W Young, Martin M Matzuk

Faculty, Staff and Students Publications

JQ1 is a small-molecule inhibitor of the bromodomain and extra terminal (BET) protein family that potently inhibits the bromodomain testis-specific protein (BRDT), which is essential for spermatogenesis. JQ1 treatment produces a reversible contraceptive effect by targeting the activity of BRDT in mouse male germ cells, validating BRDT as a male contraceptive target. Although JQ1 possesses favourable physical properties, it exhibits a short half-life. Because the details of xenobiotic metabolism play important roles in the optimization of drug candidates and in determining the role of metabolism in drug efficacy, we investigated the metabolism of JQ1 in human and mouse liver microsomes. …

A Global Slc7a7 Knockout Mouse Model Demonstrates Characteristic Phenotypes Of Human Lysinuric Protein Intolerance, Bridget M Stroup, Ronit Marom, Xiaohui Li, Chih-Wei Hsu, Cheng-Yen Chang, Luan D Truong, Brian Dawson, Ingo Grafe, Yuqing Chen, Ming-Ming Jiang, Denise Lanza, Jennie Rose Green, Qin Sun, J P Barrish, Safa Ani, Audrey E Christiansen, John R Seavitt, Mary E Dickinson, Farrah Kheradmand, Jason D Heaney, Brendan Lee, Lindsay C Burrage

Faculty, Staff and Students Publications

Lysinuric protein intolerance (LPI) is an inborn error of cationic amino acid (arginine, lysine, ornithine) transport caused by biallelic pathogenic variants in SLC7A7, which encodes the light subunit of the y+LAT1 transporter. Treatments for the complications of LPI, including growth failure, renal disease, pulmonary alveolar proteinosis, autoimmune disorders and osteoporosis, are limited. Given the early lethality of the only published global Slc7a7 knockout mouse model, a viable animal model to investigate global SLC7A7 deficiency is needed. Hence, we generated two mouse models with global Slc7a7 deficiency (Slc7a7em1Lbu/em1Lbu; Slc7a7Lbu/Lbu and Slc7a7em1(IMPC)Bay/em1(IMPC)Bay; Slc7a7Bay/Bay) using CRISPR/Cas9 technology by introducing a deletion of exons …

Gut Microbiota-Derived Short-Chain Fatty Acids Promote Poststroke Recovery In Aged Mice, Juneyoung Lee, John D'Aigle, Louise Atadja, Victoria Quaicoe, Pedram Honarpisheh, Bhanu P Ganesh, Ahmad Hassan, Joerg Graf, Joseph Petrosino, Nagireddy Putluri, Liang Zhu, David J Durgan, Robert M Bryan, Louise D Mccullough, Venugopal Reddy Venna

Faculty, Staff and Students Publications

RATIONALE: The elderly experience profound systemic responses after stroke, which contribute to higher mortality and more severe long-term disability. Recent studies have revealed that stroke outcomes can be influenced by the composition of gut microbiome. However, the potential benefits of manipulating the gut microbiome after injury is unknown.

OBJECTIVE: To determine if restoring youthful gut microbiota after stroke aids in recovery in aged subjects, we altered the gut microbiome through young fecal transplant gavage in aged mice after experimental stroke. Further, the effect of direct enrichment of selective bacteria producing short-chain fatty acids (SCFAs) was tested as a more targeted …

Reduced Intensity Conditioning For Acute Myeloid Leukemia Using Melphalan- Vs Busulfan-Based Regimens: A Cibmtr Report, Zheng Zhou, Rajneesh Nath, Jan Cerny, Hai-Lin Wang, Mei-Jie Zhang, Hisham Abdel-Azim, Vaibhav Agrawal, Gulrayz Ahmed, A Samer Al-Homsi, Mahmoud Aljurf, Hassan B Alkhateeb, Amer Assal, Ulrike Bacher, Ashish Bajel, Qaiser Bashir, Minocher Battiwalla, Vijaya Raj Bhatt, Michael Byrne, Jean-Yves Cahn, Mitchell Cairo, Hannah Choe, Edward Copelan, Corey Cutler, Moussab B Damlaj, Zachariah Defilipp, Marcos De Lima, Miguel Angel Diaz, Nosha Farhadfar, James Foran, César O Freytes, Aaron T Gerds, Usama Gergis, Michael R Grunwald, Zartash Gul, Mehdi Hamadani, Shahrukh Hashmi, Mark Hertzberg, Gerhard C Hildebrandt, Nasheed Hossain, Yoshihiro Inamoto, Luis Isola, Tania Jain, Rammurti T Kamble, Muhammad Waqas Khan, Mohamed A Kharfan-Dabaja, Partow Kebriaei, Natasha Kekre, Nandita Khera, Hillard M Lazarus, Jane L Liesveld, Mark Litzow, Hongtao Liu, David I Marks, Rodrigo Martino, Vikram Mathews, Asmita Mishra, Hemant S Murthy, Arnon Nagler, Ryotaro Nakamura, Sunita Nathan, Taiga Nishihori, Rebecca Olin, Richard F Olsson, Neil Palmisiano, Sagar S Patel, Mrinal M Patnaik, Attaphol Pawarode, Miguel-Angel Perales, Ioannis Politikos, Uday Popat, David Rizzieri, Brenda M Sandmaier, Bipin N Savani, Sachiko Seo, Nirav N Shah, Geoffrey L Uy, David Valcárcel, Leo F Verdonck, Edmund K Waller, Youjin Wang, Daniel Weisdorf, Baldeep Wirk, Eric Wong, Jean A Yared, Wael Saber

Faculty, Staff and Students Publications

There is a lack of large comparative study on the outcomes of reduced intensity conditioning (RIC) in acute myeloid leukemia (AML) transplantation using fludarabine/busulfan (FB) and fludarabine/melphalan (FM) regimens. Adult AML patients from Center for International Blood and Marrow Transplant Research who received first RIC allo-transplant between 2001 and 2015 were studied. Patients were excluded if they received cord blood or identical twin transplant, total body irradiation in conditioning, or graft-versus-host disease (GVHD) prophylaxis with in vitro T-cell depletion. Primary outcome was overall survival (OS), secondary end points were leukemia-free survival (LFS), nonrelapse mortality (NRM), relapse, and GVHD. Multivariate survival …

Etiology Of Lumbosacral Radiculoplexopathy: Sacral Insufficiency Fracture On Magnetic Resonance Imaging, Christian Geannette, Susan C Lee, Darryl B Sneag

Faculty, Staff and Students Publications

BACKGROUND: Sacral insufficiency fracture (SIF) can cause lumbosacral radiculoplexopathy (LSRP) and is probably under-recognized. Symptoms may include nonspecific lumbar spine or buttock pain that is exacerbated by physical activity and alleviated with rest. The frequency of LSRP secondary to SIF has not been reported.

QUESTIONS/PURPOSES: We aimed to determine the frequency of LSRP associated with SIF using magnetic resonance imaging (MRI) of the lumbar spine.

METHODS: We searched a radiology database at our institution using the keywords "sacral insufficiency fracture" and "lumbar spine MRI" for patient records from January 2014 through December 2017. We assessed for the presence of LSRP, …

Glycemic Control And Infections Among Us Hemodialysis Patients With Diabetes Mellitus, Jinnie J Rhee, Yuanchao Zheng, Sai Liu, Maria E Montez-Rath, Richard J Hamill, Julie H Ishida, Wolfgang C Winkelmayer

Faculty, Staff and Students Publications

INTRODUCTION: Patients with diabetes mellitus (DM) on hemodialysis (HD) may be particularly vulnerable to infections.

METHODS: We used merged data from the United States Renal Data System and electronic health records data from a large US dialysis provider to retrospectively examine the association between glycemic control and infections in these patients. Adult patients with DM aged ≥18 years who initiated in-center maintenance HD treatment from 2006 to 2011 and survived >90 days were included. Quarterly mean time-averaged hemoglobin A1c (HbA1c) values were categorized into

RESULTS: In a cohort of 33,753 eligible patients, those with higher HbA1c levels had higher rates …

Correction: Double-Blind, Placebo-Controlled, Dose-Ranging Trial Of Intravenous Ketamine As Adjunctive Therapy In Treatment-Resistant Depression (Trd), Maurizio Fava, Marlene P Freeman, Martina Flynn, Heidi Judge, Bettina B Hoeppner, Cristina Cusin, Dawn F Ionescu, Sanjay J Mathew, Lee C Chang, Dan V Iosifescu, James Murrough, Charles Debattista, Alan F Schatzberg, Madhukar H Trivedi, Manish K Jha, Gerard Sanacora, Samuel T Wilkinson, George I Papakostas

Faculty, Staff and Students Publications

Numerous placebo-controlled studies have demonstrated the ability of ketamine, an NMDA receptor antagonist, to induce rapid (within hours), transient antidepressant effects when administered intravenously (IV) at subanesthetic doses (0.5 mg/kg over 40 min). However, the optimal antidepressant dose remains unknown. We aimed to compare to active placebo the rapid acting antidepressant properties of a broad range of subanesthetic doses of IV ketamine among outpatients with treatment-resistant depression (TRD). A range of IV ketamine doses were compared to active placebo in the treatment of adult TRD over a 3-day period following a single infusion over 40 min. This was an outpatient …

Mechanistic And Translational Studies On Skeletal Malignancies, Jeremy Mcguire

USF Tampa Graduate Theses and Dissertations

New treatment strategies are desperately needed for treating skeletal malignancy. Skeletal malignancies can be either primary cancer that originated in the bone, such as osteosarcoma, or metastatic cancer that spread from another organ to the skeleton, as in the case of breast or prostate cancer. In this thesis, I will detail two projects that focus on the discovery of new treatment strategies for both primary skeletal malignancy and metastatic skeletal malignancy.

The first project focuses on the primary skeletal malignancy, osteosarcoma, a rare cancer that is commonly diagnosed in children and young adults and metastasizes to the lungs. The survival …

Nuclear Localization Of A Novel Calpain-2 Mediated Junctophilin-2 C-Terminal Cleavage Peptide Promotes Cardiomyocyte Remodeling, Satadru K Lahiri, Ann P Quick, Benoit Samson-Couterie, Mohit Hulsurkar, Ies Elzenaar, Ralph J Van Oort, Xander H T Wehrens

Faculty, Staff and Students Publications

Heart failure (HF) is a leading cause of morbidity and mortality worldwide. Patients with HF exhibit a loss of junctophilin-2 (JPH2), a structural protein critical in forming junctional membrane complexes in which excitation-contraction takes place. Several mechanisms have been proposed to mediate the loss of JPH2, one being cleavage by the calcium-dependent protease calpain. The downstream mechanisms underlying HF progression after JPH2 cleavage are presently poorly understood. In this study, we used Labcas to bioinformatically predict putative calpain cleavage sites on JPH2. We identified a cleavage site that produces a novel C-terminal JPH2 peptide (JPH2-CTP) using several domain-specific antibodies. Western …

Acute Tubular Injury In A Patient On A Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitor, June K Pickett, Maulin Shah, Michael Gillette, Peter Jones, Salim Virani, Christie Ballantyne, Vijay Nambi

Faculty, Staff and Students Publications

A 72-year-old man with coronary artery disease, statin intolerance, and chronic kidney disease stage IIIa was initiated on alirocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, and developed acute kidney injury. A kidney biopsy was performed and suggested acute tubular injury. The serum creatinine returned to baseline after discontinuation of alirocumab. (Level of Difficulty: Intermediate.)

Aav-Crispr Gene Editing Is Negated By Pre-Existing Immunity To Cas9, Ang Li, Mark R Tanner, Ciaran M Lee, Ayrea E Hurley, Marco De Giorgi, Kelsey E Jarrett, Timothy H Davis, Alexandria M Doerfler, Gang Bao, Christine Beeton, William R Lagor

Faculty, Staff and Students Publications

Adeno-associated viral (AAV) vectors are a leading candidate for the delivery of CRISPR-Cas9 for therapeutic genome editing in vivo. However, AAV-based delivery involves persistent expression of the Cas9 nuclease, a bacterial protein. Recent studies indicate a high prevalence of neutralizing antibodies and T cells specific to the commonly used Cas9 orthologs from Streptococcus pyogenes (SpCas9) and Staphylococcus aureus (SaCas9) in humans. We tested in a mouse model whether pre-existing immunity to SaCas9 would pose a barrier to liver genome editing with AAV packaging CRISPR-Cas9. Although efficient genome editing occurred in mouse liver with pre-existing SaCas9 immunity, this was accompanied by …

Myeloid-Derived Suppressor Cells Infiltration In Non-Small-Cell Lung Cancer Tumor And Mage-A4 And Ny-Eso-1 Expression, Zhenbo Hou, Xiao Liang, Xinmei Wang, Ziqiang Zhou, Guilan Shi

Bioelectrics Publications

Cancer/testis antigens melanoma‑associated antigen 4 (MAGE‑A4) and New York esophageal squamous cell carcinoma‑1 (NY‑ESO‑1) are of clinical interest as biomarkers and present valuable targets for immunotherapy; however, they are poor prognostic markers in non‑small cell lung cancer (NSCLC). In addition, myeloid derived suppressor cells (MDSCs) are recognized as a key element in tumor escape and progression. The aim of the present study was to investigate the diagnostic and prognostic value of MAGE‑A4 and NY‑ESO‑1, and their association with MDSCs in NSCLC samples. The expression levels of MAGE‑A4 and NY‑ESO‑1, and the infiltration of MDSCs (CD33+), were analyzed by immunohistochemistry of …

Rapid And Efficient Synthetic Assembly Of Multiplex Luciferase Reporter Plasmids For The Simultaneous Monitoring Of Up To Six Cellular Signaling Pathways, Alejandro Sarrion-Perdigones, Yezabel Gonzalez, Koen J T Venken

Faculty, Staff and Students Publications

High-throughput cell-based screening assays are valuable tools in the discovery of chemical probes and therapeutic agents. Such assays are designed to examine the effects of small compounds on targets, pathways, or phenotypes participating in normal and disease processes. While most cell-based assays measure single quantities, multiplexed assays seek to address these limitations by obtaining multiple simultaneous measurements. The signals from such measurements should be independently detectable and cover large dynamic ranges. Luciferases are good candidates for generation of such signals. They are genetically encoded, versatile, and cost-effective, and their output signals can be sensitively detected. We recently developed a multiplex …

Pooled Crispr Screens With Imaging On Microraft Arrays Reveals Stress Granule-Regulatory Factors, Emily C Wheeler, Anthony Q Vu, Jaclyn M Einstein, Matthew Disalvo, Noorsher Ahmed, Eric L Van Nostrand, Alexander A Shishkin, Wenhao Jin, Nancy L Allbritton, Gene W Yeo

Faculty, Staff and Students Publications

Genetic screens using pooled CRISPR-based approaches are scalable and inexpensive, but restricted to standard readouts, including survival, proliferation and sortable markers. However, many biologically relevant cell states involve cellular and subcellular changes that are only accessible by microscopic visualization, and are currently impossible to screen with pooled methods. Here we combine pooled CRISPR-Cas9 screening with microraft array technology and high-content imaging to screen image-based phenotypes (CRaft-ID; CRISPR-based microRaft followed by guide RNA identification). By isolating microrafts that contain genetic clones harboring individual guide RNAs (gRNA), we identify RNA-binding proteins (RBPs) that influence the formation of stress granules, the punctate protein-RNA …

Simultaneous Examination Of Cellular Pathways Using Multiplex Hextuple Luciferase Assaying, Alejandro Sarrion-Perdigones, Lyra Chang, Yezabel Gonzalez, Tatiana Gallego-Flores, Damian W Young, Koen J T Venken

Faculty, Staff and Students Publications

Multiplex experimentation that can assay multiple cellular signaling pathways in the same cells requires orthogonal genetically encoded reporters that report over large dynamic ranges. Luciferases are cost-effective, versatile candidates whose output signals can be sensitively detected in a multiplex fashion. Commonly used dual luciferase reporter assays detect one luciferase that is coupled to a single cellular pathway, and a second that is coupled to a control pathway for normalization purposes. We expanded this approach to multiplex hextuple luciferase assaying that can report on five cellular signaling pathways and one control, each of which is encoded by a unique luciferase. Light …

Age-Dependent Involvement Of Gut Mast Cells And Histamine In Post-Stroke Inflammation, Maria Pilar Blasco, Anjali Chauhan, Pedram Honarpisheh, Hilda Ahnstedt, John D'Aigle, Arunkumar Ganesan, Sriram Ayyaswamy, Frank Blixt, Susan Venable, Angela Major, David Durgan, Anthony Haag, Julia Kofler, Robert Bryan, Louise D Mccullough, Bhanu Priya Ganesh

Faculty, Staff and Students Publications

BACKGROUND: Risk of stroke-related morbidity and mortality increases significantly with age. Aging is associated with chronic, low-grade inflammation, which is thought to contribute to the poorer outcomes after stroke seen in the elderly. Histamine (HA) is a major molecular mediator of inflammation, and mast cells residing in the gut are a primary source of histamine.

METHODS: Stroke was induced in male C57BL/6 J mice at 3 months (young) and 20 months (aged) of age. Role of histamine after stroke was examined using young (Yg) and aged (Ag) mice; mice underwent MCAO surgery and were euthanized at 6 h, 24 h, …

Tfeb Regulates Murine Liver Cell Fate During Development And Regeneration, Nunzia Pastore, Tuong Huynh, Niculin J Herz, Alessia Calcagni', Tiemo J Klisch, Lorenzo Brunetti, Kangho Ho Kim, Marco De Giorgi, Ayrea Hurley, Annamaria Carissimo, Margherita Mutarelli, Niya Aleksieva, Luca D'Orsi, William R Lagor, David D Moore, Carmine Settembre, Milton J Finegold, Stuart J Forbes, Andrea Ballabio

Faculty, Staff and Students Publications

It is well established that pluripotent stem cells in fetal and postnatal liver (LPCs) can differentiate into both hepatocytes and cholangiocytes. However, the signaling pathways implicated in the differentiation of LPCs are still incompletely understood. Transcription Factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, is known to be involved in osteoblast and myeloid differentiation, but its role in lineage commitment in the liver has not been investigated. Here we show that during development and upon regeneration TFEB drives the differentiation status of murine LPCs into the progenitor/cholangiocyte lineage while inhibiting hepatocyte differentiation. Genetic interaction studies show that …

Proteolysis-Targeting Chimera (Protac) For Targeted Protein Degradation And Cancer Therapy, Xin Li, Yongcheng Song

Faculty, Staff and Students Publications

Proteolysis-targeting chimera (PROTAC) has been developed to be a useful technology for targeted protein degradation. A bifunctional PROTAC molecule consists of a ligand (mostly small-molecule inhibitor) of the protein of interest (POI) and a covalently linked ligand of an E3 ubiquitin ligase (E3). Upon binding to the POI, the PROTAC can recruit E3 for POI ubiquitination, which is subjected to proteasome-mediated degradation. PROTAC complements nucleic acid-based gene knockdown/out technologies for targeted protein reduction and could mimic pharmacological protein inhibition. To date, PROTACs targeting ~ 50 proteins, many of which are clinically validated drug targets, have been successfully developed with several …

A Goldenbraid Cloning System For Synthetic Biology In Social Amoebae, Peter Kundert, Alejandro Sarrion-Perdigones, Yezabel Gonzalez, Mariko Katoh-Kurasawa, Shigenori Hirose, Peter Lehmann, Koen J T Venken, Gad Shaulsky

Faculty, Staff and Students Publications

GoldenBraid is a rapid, modular, and robust cloning system used to assemble and combine genetic elements. Dictyostelium amoebae represent an intriguing synthetic biological chassis with tractable applications in development, chemotaxis, bacteria-host interactions, and allorecognition. We present GoldenBraid as a synthetic biological framework for Dictyostelium, including a library of 250 DNA parts and assemblies and a proof-of-concept strain that illustrates cAMP-chemotaxis with four fluorescent reporters coded by one plasmid.

The Current Neuroscientific Understanding Of Alzheimer's Disease, Rachel A. Brandes

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Alzheimer’s disease is a degenerative neurological illness characterized by the deterioration of brain regions implicated in memory and cognitive function. While researchers have yet to find a cure or effective treatment, they have gained a better understanding of its pathology and development. Through years of neuroscience research, scientists have discovered much of what happens in the brain during Alzheimer’s disease onset and how this causes its symptoms; many hypotheses regarding this aspect of the illness involve temporal lobe atrophy, neurofibrillary tangles, and amyloid plaques. Although Alzheimer’s disease affects millions of people every day, it seems that most are unaware of …

Investigating The Redox Sensitivity Of Mitf Splice Variants, Rachel Berryman

Senior Theses

Within pigment-producing cells known as melanocytes, the transcription factor MITF is intimately involved in regulating genes associated with cell cycle maintenance and melanocyte differentiation. Research, however, has provided conflicting results on the relationship between the expression levels of MITF and melanocyte cell fate. To complicate matters, two splice variants of MITF exist, differing by only 18 base pairs. These variants have been observed at variable levels of expression in melanocyte and melanoma cells, raising the question as to their functional purpose. Building upon previous research by the Leachman/Cassidy lab that identified the redox sensitivity of MITF while additionally establishing a …