Cell and Developmental Biology Commons^™

Dengue-Induced Autophagy, Virus Replication And Protection From Cell Death Require Er Stress (Perk) Pathway Activation, E. Datan, S. G. Roy, G. Germain, N. Zali, J. E. Mclean, G. Golshan, S. Harbajan, R. A. Lockshin, Z. Zakeri

Publications and Research

Avirus that reproduces in a host without killing cells can easily establish a successful infection. Previously, we showed that dengue-2, a virus that threatens 40% of the world, induces autophagy, enabling dengue to reproduce in cells without triggering cell death. Autophagy further protects the virus-laden cells from further insults. In this study, we evaluate how it does so; we show that dengue upregulates host pathways that increase autophagy, namely endoplasmic reticulum (ER) stress and ataxia telangiectasiamutated (ATM) signaling followed by production of reactive oxygen species (ROS). Inhibition of ER stress or ATM signaling abrogates the dengueconferred protection against other cell …

Characterization And Recombinant Expression Of Terebrid Venom Peptide From Terebra Guttata, John Moon, Juliette Gorson, Mary Elizabeth Wright, Laurel Yee, Samer Khawaja, Hye Young Shin, Yasmine Karma, Rajeeva Lochan Musunri, Michelle Yun, Mandë Holford

Publications and Research

Venom peptides found in terebrid snails expand the toolbox of active compounds that can be applied to investigate cellular physiology and can be further developed as future therapeutics. However, unlike other predatory organisms, such as snakes, terebrids produce very small quantities of venom, making it difficult to obtain sufficient amounts for biochemical characterization. Here, we describe the first recombinant expression and characterization of terebrid peptide, teretoxin Tgu6.1, from Terebra guttata. Tgu6.1 is a novel forty-four amino acid teretoxin peptide with a VI/VII cysteine framework (C–C–CC–C–C) similar to O, M and I conotoxin superfamilies. A ligation-independent cloning strategy with an ompT …

The Glucose Metabolite Methylglyoxal Inhibits Expression Of The Glucose Transport Genes By Inactivating The Cell Surface Glucose Sensors Rgt2 And Snf3 In Yeast, Adhiraj Roy, Salman Hashmi, Zerui Li, Angela Dement, Kyu Hong Cho, Jeong-Ho Kim

Biochemistry and Molecular Medicine Faculty Publications

Methylglyoxal (MG) is a cytotoxic by-product of glycolysis. MG has inhibitory effect on the growth of cells ranging from microorganisms to higher eukaryotes, but its molecular targets are largely unknown. The yeast cell-surface glucose sensors Rgt2 and Snf3 function as glucose receptors that sense extracellular glucose and generate a signal for induction of expression of genes encoding glucose transporters (HXTs). Here we provide evidence that these glucose sensors are primary targets of MG in yeast. MG inhibits the growth of glucose-fermenting yeast cells by inducing endocytosis and degradation of the glucose sensors. However, the glucose sensors with mutations …

Assembly And Structure Of Human Mitochondrial Transcription Initiation Complex, Yaroslav Morozov

Graduate School of Biomedical Sciences Theses and Dissertations

Mitochondria play a key role in energy metabolism in nearly all eukaryotic cells. Apart from that, they participate in many other biochemical pathways, such as amino acid and nucleotide metabolism, and biosynthesis of cholesterol, heme, and iron-sulfur clusters. Mitochondria are also involved in cell signaling, apoptosis and regulation of cell cycle. Abnormalities of mitochondrial morphology and function are often associated with tumor progression, neurodegeneration and aging.

Mitochondria are unique organelles in mammalian cells because they have their own genomic DNA, transcription and translation systems. Various mutations and defects in mitochondrial gene expression lead to severe diseases that include various mitochondrial …

Motor And Hippocampal Dependent Spatial Learning And Reference Memory Assessment In A Transgenic Rat Model Of Alzheimer's Disease With Stroke, Jennifer L. Au, Nina Weishaupt, Hayley J. Nell, Shawn N. Whitehead, David F. Cechetto

Anatomy and Cell Biology Publications

Alzheimer's disease (AD) is a debilitating neurodegenerative disease that results in neurodegeneration and memory loss. While age is a major risk factor for AD, stroke has also been implicated as a risk factor and an exacerbating factor. The co-morbidity of stroke and AD results in worsened stroke-related motor control and AD-related cognitive deficits when compared to each condition alone. To model the combined condition of stroke and AD, a novel transgenic rat model of AD, with a mutated form of amyloid precursor protein (a key protein involved in the development of AD) incorporated into its DNA, is given a small …

Shaping The Growth Behaviour Of Biofilms Initiated From Bacterial Aggregates, Gavin Melaugh, Jaime B. Hutchison, Kasper N. Kragh, Yasuhiko Irie, Aled E. L. Roberts, Thomas Bjarnsholt, Stephen P. Diggle, Vernita Gordon, Rosalind J. Allen

Biology Faculty Publications

Bacterial biofilms are usually assumed to originate from individual cells deposited on a surface. However, many biofilm-forming bacteria tend to aggregate in the planktonic phase so that it is possible that many natural and infectious biofilms originate wholly or partially from pre-formed cell aggregates. Here, we use agent-based computer simulations to investigate the role of pre-formed aggregates in biofilm development. Focusing on the initial shape the aggregate forms on the surface, we find that the degree of spreading of an aggregate on a surface can play an important role in determining its eventual fate during biofilm development. Specifically, initially spread …

Analysis Of Enzyme-Responsive Peptide Surfaces By Raman Spectroscopy, Jugal Kishore Sahoo, Narayana M.S. Sirimuthu, Anne Canning, Mischa Zelzer, Duncan Graham, Rein V. Ulijn

Advanced Science Research Center

We report on the use of Raman spectroscopy as a tool to characterize model peptide functionalised surfaces. By taking advantage of Raman reporters built into the peptide sequence, the enzymatic hydrolysis of these peptides could be determined.

The Role Of Hypoxia On Pyruvate Kinase M2, Mammalian Target Of Rapamycin, Mitochondrial Function, And Cell Invasion In The Trophoblast, Rebecca Lutz Kimball

Theses and Dissertations

This thesis will be organized into two chapters discussing the role of hypoxia in the human placenta. The goal of this thesis is to characterize pyruvate kinase M2, mammalian target of rapamycin, mitochondrial function, and cell invasion in hypoxic conditions in the trophoblast. Understanding the mechanisms of placental metabolism can lead to further treatments for placental diseases. Chapter one covers the background of intrauterine growth restriction, hypoxia, placental metabolism, and pyruvate kinase M2 (PKM2). Little is currently understood about the role of the mitochondria in placental diseases. Expression of PKM2, trophoblast cell invasion, and mitochondrial function is shown to be …

Explicit Time Deficit In Schizophrenia: Systematic Review And Meta-Analysis Indicate It Is Primary And Not Domain Specific, V Ciullo, G Spalletta, C Caltagirone, Re Jorge, F Piras

Faculty, Staff and Students Publications

Although timing deficits are a robust finding in schizophrenia (SZ), the notion of a genuine time perception disorder in SZ is still being debated because distortions in timing might depend on neuropsychological deficits that are characteristics of the illness. Here we used meta-analytic methods to summarize the evidence of timing deficits in SZ and moderator analyses to determine whether defective timing in SZ arises from nontemporal sources or from defective time perception. PubMed Services, PsycNET, and Scopus were searched through March 2015, and all references in articles were investigated to find other relevant studies. Studies were selected if they included …

Genome Engineering: Drosophila Melanogaster And Beyond, Kjt Venken, A Sarrion-Perdigones, Pj Vandeventer, Ns Abel, Ae Christiansen, Kl Hoffman

Faculty, Staff and Students Publications

A central challenge in investigating biological phenomena is the development of techniques to modify genomic DNA with nucleotide precision that can be transmitted through the germ line. Recent years have brought a boon in these technologies, now collectively known as genome engineering. Defined genomic manipulations at the nucleotide level enable a variety of reverse engineering paradigms, providing new opportunities to interrogate diverse biological functions. These genetic modifications include controlled removal, insertion, and substitution of genetic fragments, both small and large. Small fragments up to a few kilobases (e.g., single nucleotide mutations, small deletions, or gene tagging at single or multiple …

Ct-Based Structural Rigidity Analysis Is More Accurate Than Mirels Scoring For Fracture Prediction In Metastatic Femoral Lesions, Ta Damron, A Nazarian, V Entezari, C Brown, W Grant, N Calderon, Et Al.

Faculty, Staff and Students Publications

BACKGROUND: Controversy continues regarding the appropriate assessment of fracture risk in long bone lesions affected by disseminated malignancy. QUESTIONS/PURPOSES: The purpose of this ongoing Musculoskeletal Tumor Society-sponsored, multi-institutional prospective cross-sectional clinical study is to compare CT-based structural rigidity analysis (CTRA) with physician-derived Mirels scoring for predicting pathologic fracture in femoral bone lesions. We hypothesized CTRA would be superior to Mirels in predicting fracture risk within the first year based on (1) sensitivity, specificity, positive predictive value, and negative predictive value; (2) receiver operator characteristic (ROC) analysis; and (3) fracture prediction after controlling for potential confounding variables such as age and …

Role Of Deubiquitinating Enzymes In Dna Repair, Younghoon Kee, Tony T. Huang

Molecular Biosciences Faculty Publications

Both proteolytic and nonproteolytic functions of ubiquitination are essential regulatory mechanisms for promoting DNA repair and the DNA damage response in mammalian cells. Deubiquitinating enzymes (DUBs) have emerged as key players in the maintenance of genome stability. In this minireview, we discuss the recent findings on human DUBs that participate in genome maintenance, with a focus on the role of DUBs in the modulation of DNA repair and DNA damage signaling.

Pi(4)P Promotes Phosphorylation And Conformational Change Of Smoothened Through Interaction With Its C-Terminal Tail, Kai Jiang, Yajuan Liu, Junkai Fan, Jie Zhang, Xiang-An Li, B. Mark Evers, Haining Zhu, Jianhang Jia

Markey Cancer Center Faculty Publications

In Hedgehog (Hh) signaling, binding of Hh to the Patched-Interference Hh (Ptc-Ihog) receptor complex relieves Ptc inhibition on Smoothened (Smo). A longstanding question is how Ptc inhibits Smo and how such inhibition is relieved by Hh stimulation. In this study, we found that Hh elevates production of phosphatidylinositol 4-phosphate (PI(4)P). Increased levels of PI(4)P promote, whereas decreased levels of PI(4)P inhibit, Hh signaling activity. We further found that PI(4)P directly binds Smo through an arginine motif, which then triggers Smo phosphorylation and activation. Moreover, we identified the pleckstrin homology (PH) domain of G protein-coupled receptor kinase 2 (Gprk2) as an …

The Two-Component System Cpxra Negatively Regulates The Locus Of Enterocyte Effacement Of Enterohemorrhagic Escherichia Coli Involving Σ32 And Lon Protease, Miguel A. De La Cruz, Jason K. Morgan, Miguel A. Ares, Jorge A. Yáñez-Santos, James T. Riordan, Jorge A. Girón

Molecular Biosciences Faculty Publications

Enterohemorrhagic Escherichia coli (EHEC) is a significant cause of serious human gastrointestinal disease worldwide. EHEC strains contain a pathogenicity island called the locus of enterocyte effacement (LEE), which encodes virulence factors responsible for damaging the gut mucosa. The Cpx envelope stress response of E. coli is controlled by a two-component system (TCS) consisting of a sensor histidine kinase (CpxA) and a cytoplasmic response regulator (CpxR). In this study, we investigated the role of CpxRA in the expression of LEE-encoded virulence factors of EHEC. We found that a mutation in cpxA significantly affected adherence of EHEC to human epithelial cells. Analysis …

Non-Thermal Atmospheric Plasma Induces Ros-Independent Cell Death In U373mg Glioma Cells And Augments The Cytotoxicity Of Temozolomide, Gillian Conway, Alan Casey, Vladimir Milosavljevic, Yupeng Liu, Orla L. Howe, Patrick J. Cullen, James Curtin

Articles

Non-thermal atmospheric plasma (NTAP) is an ionised gas produced under high voltage that can generate short-lived chemically active species and induce a cytotoxic insult in cancer cells. Cell-specific resistance to NTAP-mediated cytotoxicity has been reported in the literature. The aim of this study was to determine whether resistance against NTAP could be overcome using the human glioma cell line U373MG.

Methods:

Non-thermal atmospheric plasma was generated using a Dielectric Barrier Device (DBD) system with a maximum voltage output of 120 kV at 50 Hz. The viability of U373MG GBM cells and HeLa cervical carcinoma cells was determined using morphology, flow …

Toward Repurposing Metformin As A Precision Anti-Cancer Therapy Using Structural Systems Pharmacology, Thomas Hart, Shihab Dider, Weiwei Han, Hua Xu, Zhongming Zhao, Lei Xie

Publications and Research

Metformin, a drug prescribed to treat type-2 diabetes, exhibits anti-cancer effects in a portion of patients, but the direct molecular and genetic interactions leading to this pleiotropic effect have not yet been fully explored. To repurpose metformin as a precision anti-cancer therapy, we have developed a novel structural systems pharmacology approach to elucidate metformin’s molecular basis and genetic biomarkers of action. We integrated structural proteome-scale drug target identification with network biology analysis by combining structural genomic, functional genomic, and interactomic data. Through searching the human structural proteome, we identified twenty putative metformin binding targets and their interaction models. We experimentally …

K14+ Compound Niches Are Present On The Mouse Cornea Early After Birth And Expand After Debridement Wounds., Ahdeah Pajoohesh-Ganji, Sonali Pal-Ghosh, Gauri Tadvalkar, Mary Ann Stepp

Anatomy and Regenerative Biology Faculty Publications

Background: We previously identified compound niches (CNs) at the limbal:corneal border of the mouse cornea that contain corneal epithelial progenitor cells, express Keratin 8 (K8), and goblet cell mucin Muc5AC. During re-epithelialization after 2.5 mm epithelial debridement wounds, CNs migrate onto the cornea and expand in number mimicking conjunctivalization. When CNs form during development and whether they express corneal epithelial progenitor cell enriched K14 was not known.

Results: To provide insight into corneal epithelial homeostasis, we quantify changes in expression of simple (K8, K18, K19) and stratified squamous epithelial keratins (K5, K12, K14, and K15) during postnatal development and in …

Stepping Into And Out Of The Void: Funding Dynamics Of Human Embryonic Stem Cell Research In California, Sweden, And South Korea, Noomi Weinryb, Tania M. Bubela

Office of the Provost

Nonprofit organizations and philanthropists stepped into a funding void caused by controversies over public funding of human embryonic stem cell (hESC) research. Based on interviews of 83 representatives of 53 funders, we examine the motivations and accountability structures of public agencies, corporations, fundraising dependent nonprofit organizations and philanthropic organizations that funded hESC research in three jurisdictions: California, Sweden, and South Korea. While non-traditional forms of funding are essential in the early stages of research advancement, they are unreliable for the long timeframes necessary to advance cell therapies. Such funding sources may enter the field based on high expectations, but may …

Global Regulator Of Virulence A (Grva) Coordinates Expression Of Discrete Pathogenic Mechanisms In Enterohemorrhagic Escherichia Coli Through Interactions With Gadw-Gade, Jason K. Morgan, Ronan K. Carroll, Carly M. Harro, Khoury W Vendura, Lindsey N. Shaw, James T. Riordan

Molecular Biosciences Faculty Publications

UNLABELLED: Global regulator of virulence A (GrvA) is a ToxR-family transcriptional regulator that activates locus of enterocyte effacement (LEE)-dependent adherence in enterohemorrhagic Escherichia coli (EHEC). LEE activation by GrvA requires the Rcs phosphorelay response regulator RcsB and is sensitive to physiologically relevant concentrations of bicarbonate, a known stimulant of virulence systems in intestinal pathogens. This study determines the genomic scale of GrvA-dependent regulation and uncovers details of the molecular mechanism underlying GrvA-dependent regulation of pathogenic mechanisms in EHEC. In a grvA-null background of EHEC strain TW14359, RNA sequencing analysis revealed the altered expression of over 700 genes, including the downregulation …

Analogous Cellular Contribution And Healing Mechanisms Following Digit Amputation And Phalangeal Fracture In Mice, Lindsay A. Dawson, Jennifer Simkin, Michelle Sauque, Maegan Pela, Teresa Palkowski, Ken Muneoka

Biology Faculty Publications

Regeneration of amputated structures is severely limited in humans and mice, with complete regeneration restricted to the distal portion of the terminal phalanx (P3). Here, we investigate the dynamic tissue repair response of the second phalangeal element (P2) post amputation in the adult mouse, and show that the repair response of the amputated bone is similar to the proximal P2 bone fragment in fracture healing. The regeneration-incompetent P2 amputation response is characterized by periosteal endochondral ossification resulting in the deposition of new trabecular bone, corresponding to a significant increase in bone volume; however, this response is not associated with bone …

Chamber-Specific Patterns Of Epicardium Formation In Zebrafish, Sana Khan

Dissertations, Theses, and Capstone Projects

The outer cardiac layer, the epicardium, coordinates the final steps of vertebrate heart development. This cardiac tissue arises from cells in the proepicardial organ (PEO) that forms around the base of the inflow tract. Its general location is conserved across species despite morphological differences. Cellular mechanisms of migration differ across species. Three strategies of PEO migration are described: 1) The floating cyst model - PEO cells released into the pericardial cavity are directed by fluid movements to migrate onto the myocardium; 2) Villi transfer - cardiac contractions may mediate multicellular PEO villi contact to the myocardium; and 3) Tissue bridge-mediated …

Deciphering The Role Of Gfi1b Gene Target Rgs18 In Erythro-Megakaryocytic Lineage Divergence, Ananya Sengupta

Dissertations, Theses, and Capstone Projects

The molecular programs that govern the specification of erythroid and megakaryocytic lineages remain incompletely defined. Gene targeting experiments have shown the transcriptional repressor Gfi (Growth factor independence) 1b to be essential for the generation of both erythroid and megakaryocyte cells. Transcriptional repression of Gfi1b target genes is mediated mainly by the cofactors LSD (lysine demethylase) 1 and CoREST/Rcor1 (REST corepressor 1) or other Rcor factors. To understand the mechanism of Gfi1b action, its target genes were identified by chromatin immunoprecipitation (ChIP on Chip) screens. In this study we present the role of Rgs18 (Regulator of G protein signaling 18), a …

Decorin As A Multivalent Therapeutic Agent Against Cancer., Thomas Neill, Liliana Schaefer, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin is a prototypical small leucine-rich proteoglycan that epitomizes the multifunctional nature of this critical gene family. Soluble decorin engages multiple receptor tyrosine kinases within the target-rich environment of the tumor stroma and tumor parenchyma. Upon receptor binding, decorin initiates signaling pathways within endothelial cells downstream of VEGFR2 that ultimately culminate in a Peg3/Beclin 1/LC3-dependent autophagic program. Concomitant with autophagic induction, decorin blunts capillary morphogenesis and endothelial cell migration, thereby significantly compromising tumor angiogenesis. In parallel within the tumor proper, decorin binds multiple RTKs with high affinity, including Met, for a multitude of oncosuppressive functions including growth inhibition, tumor cell …

High Genetic Diversity But Low Population Structure In The Frog Pseudopaludicola Falcipes (Hensel, 1867) (Amphibia, Anura) From The Pampas Of South America, José A. Langone, Arley Camargo, Rafael O. De Sá

Biology Faculty Publications

Relative to South America’s ecoregions, the temperate grasslands of the Pampas have been poorly studied from a phylogeographic perspective. Based on an intermediate biogeographic setting between subtropical forest (Atlantic Forest) and arid ecosystems (Chaco and Patagonia), Pampean species are expected to show unstable demographic histories due to the Quaternary climatic oscillations. Herein, we investigate the phylogenetic relatedness and phylogeographic history of Pseudopaludicola falcipes, a small and common frog that is widely distributed across the Pampean grasslands. First, we use molecular data to assess if P. falcipes represents a single or multiple, separately evolving cryptic lineages. Because P. falcipes is …

Role Of Bec-1/Beclin 1 And Autophagy Genes In C.Elegans Germline Cell Proliferation, Kristina Ames

Dissertations, Theses, and Capstone Projects

Autophagy is an evolutionary conserved process involved in the cellular adaptation to stress and basal levels of autophagy are crucial for cellular metabolism and homeostasis. Cellular recycling by autophagy is characterized by the formation of distinctive double-membrane vesicles (autophagosomes) that engulf unnecessary cytoplasmic components, such as organelles and long-lived proteins. Failure to remove protein aggregates and/or damaged organelles, via autophagy, has been implicated in various medical conditions such as liver disease, neurodegenerative diseases and cancer. Autophagy may suppress or promote cellular proliferation in tumors, depending on the type and metabolic state of the cell, where autophagy is generally believed to …

Lim Protein Ajuba Participates In The Repression Of Atr-Mediated Dna Damage Response In Human Cells, Sampada Kalan

Dissertations, Theses, and Capstone Projects

LIM proteins constitute a superfamily characterized by the presence of specialized domains called LIM. LIM domain is a unique double-zinc finger motif found in a variety of proteins and is mainly involved in protein-protein interactions. Previous work has implicated that members of the Zyxin subfamily of LIM proteins, namely TRIP6 and LPP are involved in the repression of the DNA damage response (DDR) at telomeres. We further explore if another member from this family has an influence on DDR prevention in the cells. Here, we describe a novel role for Ajuba, a Zyxin family LIM protein, in repressing inappropriate activation …

Glial Contributions To Neural Function And Disease, Mn Rasband

Faculty, Staff and Students Publications

The nervous system consists of neurons and glial cells. Neurons generate and propagate electrical and chemical signals, whereas glia function mainly to modulate neuron function and signaling. Just as there are many different kinds of neurons with different roles, there are also many types of glia that perform diverse functions. For example, glia make myelin; modulate synapse formation, function, and elimination; regulate blood flow and metabolism; and maintain ionic and water homeostasis to name only a few. Although proteomic approaches have been used extensively to understand neurons, the same cannot be said for glia. Importantly, like neurons, glial cells have …

Eosinophilic Esophagitis In Children And Its Relationship With Parental Allergies: Texas Children's Hospital Experience, G Hiremath, D Byramji, A Pacheco, G Constantine, C Davis, R Shulman, A Olive

Faculty, Staff and Students Publications

BACKGROUND: Eosinophilic esophagitis (EoE) is an allergen-mediated, clinicopathological condition affecting all ages. The characteristics of children with EoE in the southwestern USA have not been fully described. Furthermore, very little is known about the relationship between parental allergies and risk of EoE in their offspring in this patient population. AIMS: To characterize children with EoE and to examine the relationship between prevalence of parental allergies and occurrence of EoE in their offspring at a single referral pediatric center in the southwestern USA. METHODS: Demographic and clinical information of 126 children (=18 years of age) with EoE was abstracted in a …

Early Rescue Of Interneuron Disease Trajectory In Developmental Epilepsies, Ms Siehr, Jl Noebels

Faculty, Staff and Students Publications

The discovery of over 150 monogenic epilepsies and advances in early genetic diagnoses have launched a search for molecular strategies and developmental timetables to reverse or even prevent the course of these debilitating brain disorders. Orthologous rodent models of key disease genes are providing important examples of the range of targets, and serve as valuable test systems for perinatal therapeutic approaches. While gene-specific analyses of single rare 'orphan' diseases are each narrow in scope, they illuminate downstream pathways converging onto interneurons, and treatments that strengthen inhibition during cortical maturation may provide broad protection against these seemingly disparate gene errors. Several …

Efficacy Of Psychosocial Interventions In Inducing And Maintaining Alcohol Abstinence In Patients With Chronic Liver Disease: A Systematic Review, A Khan, A Tansel, Dl White, Wt Kayani, Wt Bano, J Lindsay, Hb El-Serag, F Kanwal

Faculty, Staff and Students Publications

BACKGROUND & AIMS: We conducted a systematic review of efficacy of psychosocial interventions in inducing or maintaining alcohol abstinence in patients with chronic liver disease (CLD) and alcohol use disorder (AUD). METHODS: We performed structured keyword searches in PubMed, PsychINFO, and MEDLINE for original research articles that were published from January 1983 through November 2014 that evaluated the use of psychosocial interventions to induce or maintain alcohol abstinence in patients with CLD and AUD. RESULTS: We identified 13 eligible studies that comprised 1945 patients; 5 were randomized controlled trials (RCTs). Delivered therapies included motivational enhancement therapy, cognitive behavioral therapy (CBT), …