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Articles 1 - 22 of 22
Full-Text Articles in Enzymes and Coenzymes
Increased Intermembrane Space [Ca2+] Drives Mitochondrial Structural Damage In Cpvt, Shanna Hamilton, Radmila Terentyeva, Roland Veress, Fruzsina Perger, Zuzana Nichtova, Mark Bannister, Jinxi Wang, Sage Quiggle, Rachel Battershell, Matthew Gorr, Sandor Györke, Bum-Rak Choi, Christopher George, Andriy Belevych, György Csordás, Dmitry Terentyev
Increased Intermembrane Space [Ca2+] Drives Mitochondrial Structural Damage In Cpvt, Shanna Hamilton, Radmila Terentyeva, Roland Veress, Fruzsina Perger, Zuzana Nichtova, Mark Bannister, Jinxi Wang, Sage Quiggle, Rachel Battershell, Matthew Gorr, Sandor Györke, Bum-Rak Choi, Christopher George, Andriy Belevych, György Csordás, Dmitry Terentyev
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
BACKGROUND: Mitochondrial dysfunction caused by abnormally high RyR2 (ryanodine receptor) activity is a common finding in cardiovascular diseases. Mechanisms linking RyR2 gain of function with mitochondrial remodeling remain elusive. We hypothesized that RyR2 hyperactivity in cardiac disease increases [Ca 2+ ] in the mitochondrial intermembrane space (IMS) and activates the Ca 2+ -sensitive protease calpain, driving remodeling of mitochondrial cristae architecture through cleavage of structural protein OPA1 (optic atrophy protein 1).
METHODS: We generated a highly arrhythmogenic rat model of catecholaminergic polymorphic ventricular tachycardia, induced by RyR2 gain-of-function mutation S2236L(Ser2336Leu)(+/-) . We created a new biosensor to measure IMS-[Ca2+ ] …
Protein-Protein Interaction–Interfering Peptide Rescues Dysregulated Nmda Receptor Signaling, Robert E. Featherstone, Hongbin Li, Ameet S. Sengar, Karin E. Borgmann-Winter, Olya Melnychenko, Lindsey M. Crown, Ray L. Gifford, Felix Amirfathi, Anamika Banerjee, Aivi Tran, Krishna Parekh, Margaret Heller, Wenyu Zhang, Robert J. Gallop, Adam D. Marc, Pragya Komal, Michael W. Salter, Steven J. Siegel, Chang-Gyu Hahn
Protein-Protein Interaction–Interfering Peptide Rescues Dysregulated Nmda Receptor Signaling, Robert E. Featherstone, Hongbin Li, Ameet S. Sengar, Karin E. Borgmann-Winter, Olya Melnychenko, Lindsey M. Crown, Ray L. Gifford, Felix Amirfathi, Anamika Banerjee, Aivi Tran, Krishna Parekh, Margaret Heller, Wenyu Zhang, Robert J. Gallop, Adam D. Marc, Pragya Komal, Michael W. Salter, Steven J. Siegel, Chang-Gyu Hahn
Farber Institute for Neuroscience Faculty Papers
The complex and heterogeneous genetic architecture of neuropsychiatric illnesses compels us to look beyond individual risk genes for therapeutic strategies and target the interactive dynamics and convergence of their protein products. A mechanistic substrate for convergence of synaptic neuropsychiatric risk genes are protein-protein interactions (PPIs) in the N-methyl-D-aspartate receptor (NMDAR) complex. NMDAR hypofunction in schizophrenia is associated with hypoactivity of Src kinase, resulting from convergent alterations in PPIs of Src with its partners. Of these, the association of Src with PSD-95, which inhibits the activity of this kinase in the NMDAR complex, is known to be increased in schizophrenia. Here, …
The C-Terminal Phdvc5hch Tandem Domain Of Nsd2 Is A Combinatorial Reader Of Modified H3k4 And Tri-Methylated H3k27 That Regulates Transcription Of Cell Adhesion Genes In Multiple Myeloma, Andrea Berardi, Charlotte Leonie Kaestner, Michela Ghitti, Giacomo Quilici, Paolo Cocomazzi, Jianping Li, Federico Ballabio, Chiara Zucchelli, Stefan Knapp, Jonathan Licht, Giovanna Musco
The C-Terminal Phdvc5hch Tandem Domain Of Nsd2 Is A Combinatorial Reader Of Modified H3k4 And Tri-Methylated H3k27 That Regulates Transcription Of Cell Adhesion Genes In Multiple Myeloma, Andrea Berardi, Charlotte Leonie Kaestner, Michela Ghitti, Giacomo Quilici, Paolo Cocomazzi, Jianping Li, Federico Ballabio, Chiara Zucchelli, Stefan Knapp, Jonathan Licht, Giovanna Musco
Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers
Histone methyltransferase NSD2 (MMSET) overexpression in multiple myeloma (MM) patients plays an important role in the development of this disease subtype. Through the expansion of transcriptional activating H3K36me2 and the suppression of repressive H3K27me3 marks, NSD2 activates an aberrant set of genes that contribute to myeloma growth, adhesive and invasive activities. NSD2 transcriptional activity also depends on its non-catalytic domains, which facilitate its recruitment to chromatin through histone binding. In this study, using NMR, ITC and molecular dynamics simulations, we show that the tandem PHD domain of NSD2 (PHDVC5HCHNSD2) is a combinatorial reader of unmodified histone H3K4 and tri-methylated H3K27 …
Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux
Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux
Theses and Dissertations (Comprehensive)
Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …
Opa1 And Disease-Causing Mutants Perturb Mitochondrial Nucleoid Distribution, J. Macuada, I. Molina-Riquelme, G. Vidal, N. Pérez-Bravo, C. Vásquez-Trincado, G. Aedo, D. Lagos, P. Yu-Wai-Man, R. Horvath, T. J. Rudge, B. Cartes-Saavedra, V. Eisner
Opa1 And Disease-Causing Mutants Perturb Mitochondrial Nucleoid Distribution, J. Macuada, I. Molina-Riquelme, G. Vidal, N. Pérez-Bravo, C. Vásquez-Trincado, G. Aedo, D. Lagos, P. Yu-Wai-Man, R. Horvath, T. J. Rudge, B. Cartes-Saavedra, V. Eisner
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Optic atrophy protein 1 (OPA1) mediates inner mitochondrial membrane (IMM) fusion and cristae organization. Mutations in OPA1 cause autosomal dominant optic atrophy (ADOA), a leading cause of blindness. Cells from ADOA patients show impaired mitochondrial fusion, cristae structure, bioenergetic function, and mitochondrial DNA (mtDNA) integrity. The mtDNA encodes electron transport chain subunits and is packaged into nucleoids spread within the mitochondrial population. Nucleoids interact with the IMM, and their distribution is tightly linked to mitochondrial fusion and cristae shaping. Yet, little is known about the physio-pathological relevance of nucleoid distribution. We studied the effect of OPA1 and ADOA-associated mutants on …
The Effects Of Sex On Zebrafish Bone Metabolism, Simon Bagatto
The Effects Of Sex On Zebrafish Bone Metabolism, Simon Bagatto
Williams Honors College, Honors Research Projects
I investigated the effects of diet and sex on zebrafish bone metabolism. Zebrafish were subjected to either a high-calorie or low-calorie diet over a five-week period. After this diet, zebrafish scales were used to measure alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) enzyme activity with a fluorescent substrate. The enzyme activities were markers of the osteoblasts (ALP) and the osteoclasts (TRAP). These data were compared among sex and diet of the zebrafish using a repeated measures ANOVA statistical test. I also measured the number of resorption lacunae per scale (another indicator of osteoclast activity). The results showed higher TRAP …
Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel
Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel
Masters Theses
Drug metabolism is the biochemical process of modifying drugs to detoxify and remove them through enzymatic transformations. These biotransformation’s occur primarily in the liver and are critical to understanding how pharmaceutical compounds are chemically altered inside the human body. Human carboxylesterases (CESs) catalyze the hydrolysis of esters, amides, thioesters, and carbamates. CES-mediated hydrolysis plays an important role in the metabolism of many drugs including the first FDA approved antiviral treatment for COVID-19, remdesivir (Veklury), the seizure control medication rufinamide (Banzel), and the flu antiviral drug oseltamivir (Tamiflu). CES activity is known to be influenced by a variety of factors including …
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
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 Gαs so it was long assumed that all ACs are activated by Gαs-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form …
The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber
The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber
Dissertations, Theses, and Capstone Projects
Light provides organisms with energy and spatiotemporal information. To survive and adapt, organisms have developed the ability to sense light to drive biochemical effects that underlie vision, entrainment of circadian rhythm, stress response, virulence, and many other important molecularly driven responses. Blue-light sensing Light-Oxygen-Voltage (LOV) domains are ubiquitous across multiple kingdoms of life and modulate various physiological events via diverse effector domains. Using a small molecule flavin chromophore, the LOV domain undergoes light-dependent structural changes leading to activation or repression of these catalytic and non-catalytic effectors. In silico analyses of high-throughput genomic sequencing data has led to the marked expansion …
Targeting Plasma Membrane Phosphatidylserine Content To Inhibit Oncogenic Kras Function, Walaa E. Kattan
Targeting Plasma Membrane Phosphatidylserine Content To Inhibit Oncogenic Kras Function, Walaa E. Kattan
Dissertations and Theses (Open Access)
The small GTPase KRAS, which is frequently mutated in human cancers, must be localized to the plasma membrane (PM) for biological activity. We recently showed that the KRAS C-terminal membrane anchor exhibits exquisite lipid-binding specificity for select species of phosphatidylserine (PtdSer). We therefore investigated whether reducing PM PtdSer content is sufficient to abrogate KRAS oncogenesis. Oxysterol-related binding proteins ORP5 and ORP8 exchange PtdSer synthesized in the ER for phosphatidylinositol-4-phosphate (PI4P) synthesized in the PM. We show that depletion of ORP5 or ORP8 reduced PM PtdSer levels, resulting in extensive mislocalization of KRAS from the PM. Concordantly, ORP5 or ORP8 depletion …
Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky
Anatomy And Physiology Preparatory Course Textbook (2nd Edition), Carlos Liachovitzky
Open Educational Resources
The goal of this preparatory textbook is to give students a chance to become familiar with some terms and some basic concepts they will find later on in the Anatomy and Physiology course, especially during the first few weeks of the course.
Organization and functioning of the human organism are generally presented starting from the simplest building blocks, and then moving into levels of increasing complexity. This textbook follows the same presentation. It begins introducing the concept of homeostasis, then covers the chemical level, and later on a basic introduction to cellular level, organ level, and organ system level. This …
“Do We Know Jack” About Jak? A Closer Look At Jak/Stat Signaling Pathway, Emira Bousoik, Hamidreza Montazeri Aliabadi
“Do We Know Jack” About Jak? A Closer Look At Jak/Stat Signaling Pathway, Emira Bousoik, Hamidreza Montazeri Aliabadi
Pharmacy Faculty Articles and Research
Janus tyrosine kinase (JAK) family of proteins have been identified as crucial proteins in signal transduction initiated by a wide range of membrane receptors. Among the proteins in this family JAK2 has been associated with important downstream proteins, including signal transducers and activators of transcription (STATs), which in turn regulate the expression of a variety of proteins involved in induction or prevention of apoptosis. Therefore, the JAK/STAT signaling axis plays a major role in the proliferation and survival of different cancer cells, and may even be involved in resistance mechanisms against molecularly targeted drugs. Despite extensive research focused on the …
Pde8 Is Expressed In Human Airway Smooth Muscle And Selectively Regulates Camp Signaling By Β 2 Ar-Ac6, Timothy B. Johnstone, Kaitlyn H. Smith, Cynthia J. Koziol-White, Fengying Li, Austin G. Kazarian, Maia L. Corpuz, Maya Shumyachter, Frederick J. Ehlert, Bianca E. Himes, Reynold A. Pannettieri Jr., Rennolds S. Ostrom
Pde8 Is Expressed In Human Airway Smooth Muscle And Selectively Regulates Camp Signaling By Β 2 Ar-Ac6, Timothy B. Johnstone, Kaitlyn H. Smith, Cynthia J. Koziol-White, Fengying Li, Austin G. Kazarian, Maia L. Corpuz, Maya Shumyachter, Frederick J. Ehlert, Bianca E. Himes, Reynold A. Pannettieri Jr., Rennolds S. Ostrom
Pharmacy Faculty Articles and Research
Two cAMP signaling compartments centering around adenylyl cyclase (AC) exist in human airway smooth muscle (HASM) cells, one containing ß2AR-AC6 and another containing E prostanoid receptors (EPR)-AC2. We hypothesized that different phosphodiesterase (PDE) isozymes selectively regulate cAMP signaling in each compartment. According to RNA-seq data, 18 of 24 PDE genes were expressed in primary HASM cells derived from age- and gender-matched donors with and without asthma. PDE8A was the third most abundant of the cAMP-degrading PDE genes, after PDE4A and PDE1A. Knockdown of PDE8A using shRNA evoked 2-fold greater cAMP responses to 1 DM forskolin in the presence of IBMX. …
Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski
Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski
Toxicology and Cancer Biology Faculty Publications
Ultraviolet light (UV) is an inducer of reactive oxygen species (ROS) as well as 6-4-photoproducts and cyclobutane pyrimidine dimers (CPD) in the skin, which further cause damage to the skin cells. Irradiation of cultured human melanocytes with UVB stimulated ROS production, which was reduced in cells treated with melatonin or its metabolites: 6-hydroxymelatonin (6-OHM), N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N-acetylserotonin (NAS), and 5-methoxytryptamine (5-MT). Melatonin and its derivatives also stimulated the expression of NRF2 (nuclear factor erythroid 2 [NF-E2]-related factor 2) and its target enzymes and proteins that play an important role in cell protection from different damaging factors including UVB. Silencing …
Human Anatomy And Physiology Preparatory Course: Part 1 Of 4 (Interactive), Carlos Liachovitzky
Human Anatomy And Physiology Preparatory Course: Part 1 Of 4 (Interactive), Carlos Liachovitzky
Open Educational Resources
The overall purpose of these preparatory course set of learning objectives is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.
These 40+ learning objectives to prepare for Human Anatomy and Physiology can be downloaded and played in a desktop, or laptop (windows exe file).
The entire course has four parts:
Each learning objective is followed by a set of multiple choice question similar to those found later in a Human Anatomy and Physiology course.
The organization and …
Normal Glycolytic Enzyme Activity Is Critical For Hypoxia Inducible Factor-1a Activity And Provides Novel Targets For Inhibiting Tumor Growth, Geoffrey Grandjean Phd
Normal Glycolytic Enzyme Activity Is Critical For Hypoxia Inducible Factor-1a Activity And Provides Novel Targets For Inhibiting Tumor Growth, Geoffrey Grandjean Phd
Dissertations and Theses (Open Access)
Normal Glycolytic Enzyme Activity is Critical for Hypoxia Inducible Factor-1α Activity and Provides Novel Targets for Inhibiting Tumor Growth
By Geoffrey Grandjean
Advisory Professor: Garth Powis, D. Phil
Unique to proliferating cancer cells is the observation that their increased need for energy is provided by a high rate of glycolysis followed by lactic acid fermentation in a process known as the Warburg Effect, a process many times less efficient than oxidative phosphorylation employed by normal cells to satisfy a similar energy demand [1]. This high rate of glycolysis occurs regardless of the concentration of oxygen in the cell and …
Src Homology 2 Domain-Containing 5’-Inositol Phosphatase-2 (Ship2) Is An Effector Of Lymphatic Dysfunction, Germaine D. Agollah
Src Homology 2 Domain-Containing 5’-Inositol Phosphatase-2 (Ship2) Is An Effector Of Lymphatic Dysfunction, Germaine D. Agollah
Dissertations and Theses (Open Access)
The lymphatic system is essential for the transport of excess fluid, protein, and foreign materials from interstitial tissues to lymph nodes; for immune surveillance, and to maintain fluid homeostasis. Dysregulated lymphatics can be attributed to pathological conditions including tumor metastasis, inflammation, chronic wounds, obesity, blood vascular disorders, and lymphedema. Of these, lymphedema is the most extreme of lymphatic disorders and is represented by a spectrum of symptoms ranging from mild, subtle presentation to severe, disfiguring, overt presentation. Lymphedema is more manageable in the early stages of disease but severely reduces quality of life with progression. Due to lack of molecular …
Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky
Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky
Open Educational Resources
The overall purpose of this preparatory course textbook is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.
The organization and functioning of the human organism generally is discussed in terms of different levels of increasing complexity, from the smallest building blocks to the entire body. This Anatomy and Physiology preparatory course covers the foundations on the chemical level, and a basic introduction to cellular level, organ level, and organ system levels. There is also an introduction to homeostasis at the beginning.
A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel
A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel
CMC Senior Theses
The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …
The Effects Of Glutathione On Human Keratinocyte, Manisha N. Trivedi
The Effects Of Glutathione On Human Keratinocyte, Manisha N. Trivedi
Theses and Dissertations in Biomedical Sciences
Cultured human keratinocytes were grown in vitro to assess the effects of glutathione, a thiol, on human keratinocyte proliferation. Single keratinocytes were harvested from newborn (greater than 5 days old) foreskin and were grown in culture flasks such that experiments could be performed in approximately 2 to 3 weeks. In order to evaluate the effects of glutathione (GSH) on keratinocyte growth, experiments were performed to determine the growth curve, plating efficiency, and incorporation of radiolabelled thymidine. Growth studies, performed with different concentrations of glutathione, revealed that 0.065 μM was the most effective concentration when compared to control cell cultures, and …
Determination Of Human Sperm Cell Acrosin Activity From Normal And Subfertile Men, Dilrowshan H. Haque
Determination Of Human Sperm Cell Acrosin Activity From Normal And Subfertile Men, Dilrowshan H. Haque
Chemistry & Biochemistry Theses & Dissertations
Acrosin is an acrosomal enzyme which is reported to be involved in sperm penetration through cumulus, zona, and ooplasma. This enzyme has been reported to be significantly lower in sperm of infertile men compared to sperm of fertile men. The acrosin assay which has been developed can be used for studies in patients with suspected infertility and may be used on a fraction of most semen specimens being evaluated in a clinical andrology laboratory.
Within-run precision studies yielded coefficients of variation of 11% for a low-activity pool and 9% for normalactivity pool specimens. Between-run precision studies using a single donor …
In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup
In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup
Chemistry & Biochemistry Theses & Dissertations
An assay procedure for in vitro enzymatic methylation of mannnalian ribosomal RNA has been developed in this study. The assay procedure, utilized for the comparison of normal and neoplastic methylase activities (using mouse liver and Ehrlich ascites cells as sources of enzyme), is a modification of previously published methods (52,53). A 100,000 x g supernatant (SlOO) enzyme preparation was incubated with 28S-5.8S rRNA and tritium-labeled S-adenosyl-L-methionine. The RNA was extracted, applied to DEAE cellulose paper, washed, and the radioactivity counted. The neoplastic cell methylase preparation was more active in methylating both exogenous neoplastic and normal 28S-5.8S rRNA than the normal …