Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Life Sciences

A Novel Role Of Human Dna Damage Checkpoint Protein Atr In Suppressing Ca2+ Overload-Induced Parp1-Mediated Necrosis, Hui Wang-Heaton Dec 2016

A Novel Role Of Human Dna Damage Checkpoint Protein Atr In Suppressing Ca2+ Overload-Induced Parp1-Mediated Necrosis, Hui Wang-Heaton

Electronic Theses and Dissertations

Ataxia telangiectasia and Rad3-related (ATR) is well known for its regulatory role in DNA damage responses (DDR) as a checkpoint kinase that phosphorylates hundreds of protein substrates. However, its role in cellular non-DNA damage stress responses (NDDR) is unknown. Necrosis is one form of cell death and traditionally has been regarded as a passive and uncontrolled cell death. Recently, evidence has emerged to support the concept that necrosis also may occur in a programmed manner and that PARP1 can be a mediator. Active poly (ADP-ribose) polymerase 1 (PARP1) hydrolyzes nicotinamide adenine dinucleotide (NAD+) to produce poly (ADP-ribose) (PAR) …


Investigation Of Novel Functions For Dna Damage Response And Repair Proteins In Escherichia Coli And Humans, Benjamin A. Hilton May 2016

Investigation Of Novel Functions For Dna Damage Response And Repair Proteins In Escherichia Coli And Humans, Benjamin A. Hilton

Electronic Theses and Dissertations

Endogenous and exogenous agents that can damage DNA are a constant threat to genome stability in all living cells. In response, cells have evolved an array of mechanisms to repair DNA damage or to eliminate the cells damaged beyond repair. One of these mechanisms is nucleotide excision repair (NER) which is the major repair pathway responsible for removing a wide variety of bulky DNA lesions. Deficiency, or mutation, in one or several of the NER repair proteins is responsible for many diseases, including cancer. Prokaryotic NER involves only three proteins to recognize and incise a damaged site, while eukaryotic NER …


Role Of Microrna-21 In Atherogenesis., Rihab Hamed-Berair May 2016

Role Of Microrna-21 In Atherogenesis., Rihab Hamed-Berair

Electronic Theses and Dissertations

MicroRNA-21 (miR-21) is an evolutionarily conserved microRNA, abundant in most cardiovascular tissues. It has been implicated in the pathogenesis of several cardiovascular diseases including restenosis, myocardial infarction, and heart failure. However, little is known about the contribution of miR-21 in atherosclerosis. My data show that expression of miR-21 is increased by >1.5-fold in murine atherosclerotic lesions and by 1.5-2.0-fold in the macrophages of Western diet (WD)-fed LDLR-KO mice (for 12-20 weeks). In vitro, LDL, oxidized LDL, acetylated LDL and LPS induced miR-21 by 2-4-fold and down-regulated its target protein, PDCD4, in bone marrow-derived macrophages. Basally, macrophages isolated from miR-21-KO …


Modulation Of Cell Death Signaling And Cell Proliferation By The Interaction Of Homoserine Lactones And Paraoxonase 2., Aaron Mackallan Neely May 2016

Modulation Of Cell Death Signaling And Cell Proliferation By The Interaction Of Homoserine Lactones And Paraoxonase 2., Aaron Mackallan Neely

Electronic Theses and Dissertations

Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule that functions to facilitate bacteria-bacteria communication. C12 has also been reported to affect many aspects of human host cell physiology, including evoking cell death in various types of cells. However, the signaling pathway(s) leading to C12-triggerred cell death remains unclear. To clarify cell death signaling induced by C12, we examined mouse embryonic fibroblasts (MEFs) deficient in one or more caspases. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in cells, probably through the direct induction of mitochondrial membrane permeabilization. Previous studies indicate that …


A Fret Investigation Into Molecular Mechanisms Of Cardiac Troponin Activation In Reconstituted Thin Filaments, Maria Eleni Moutsoglou Jan 2016

A Fret Investigation Into Molecular Mechanisms Of Cardiac Troponin Activation In Reconstituted Thin Filaments, Maria Eleni Moutsoglou

Electronic Theses and Dissertations

Cardiomyopathies (CM) are the leading cause of death in America, and can develop from mutations in sarcomeric proteins, leading to altered protein structure and function. Current therapies target upstream signaling pathways to treat the symptoms of heart failure, but are associated with increased mortality by affecting downstream signaling pathways and other muscle types. Rational drug design can develop therapies to treat CM at the protein level. However, a detailed knowledge of how sarcomeric proteins regulate muscle contraction is required. Muscle contraction occurs through a cyclic interaction between actin thin and myosin thick filaments, regulated by intracellular Ca2+ concentration. Troponin (Tn), …


Functional Effects Of Calcium Regulation Of Thin Filaments At Single Particle Resolution, Christopher Solis-Ocampo Jan 2016

Functional Effects Of Calcium Regulation Of Thin Filaments At Single Particle Resolution, Christopher Solis-Ocampo

Electronic Theses and Dissertations

Heart disease is the leading cause of death in the United States. Understanding heart function at the molecular level is critical for developing of more effective treatments. In the cardiac muscle, the thin filament is composed by troponin (Tn), tropomyosin (Tm), and F-actin. It provides Ca2+-dependent regulation of contraction by modulating myosin attachment and force generation in a cooperative scheme. However, this mechanism remains unclear. To understand thin filament activation, we studied the binding and functional properties of Tn and Tm to F-actin at single particle resolution by employing fluorescence image colocalization, in vitro motility assays, and Förster resonance energy …


Towards Structural Determination Of Human Α1-Glycine Receptor Allostery, Rathna Jyothi Veeramachaneni Jan 2016

Towards Structural Determination Of Human Α1-Glycine Receptor Allostery, Rathna Jyothi Veeramachaneni

Electronic Theses and Dissertations

Recent advances in technology have led to the determination of numerous notable structures of membrane proteins. While they provide valuable information about the structure of membrane proteins these studies often provide static images with potentially limited dynamics, and structural determination often requires truncation of flexible regions, and often utilizes bacterial homologs given the need for stable, heterologous overexpression. In order to better understand allostery at a molecular level, state-dependent crosslinking studies coupled with multidimensional mass spectrometry (MS) were conducted on glycine receptor (GlyR) stabilized in different allosteric states. Predominant allosteric states were stabilized using wild type or mutated receptor in …


Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan Jan 2016

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …


C-Reactive Protein Interactions With Cellular Membranes And Supported Lipid Bilayers, Aml Abd Alhamed Alnaas Jan 2016

C-Reactive Protein Interactions With Cellular Membranes And Supported Lipid Bilayers, Aml Abd Alhamed Alnaas

Electronic Theses and Dissertations

C-reactive protein (CRP) is a serum protein that binds to damaged membranes and initiates the complement immune response. Different forms of CRP are thought to alter how the body responds to inflammation and the degradation of foreign material. Despite knowing that a modified form of CRP(mCRP) binds to downstream protein binding partners better than the native pentameric form, the role of CRP conformation on lipid binding is yet unknown. In this work, three main assays were performed to characterize how conformation affects CRP-membrane interactions. The first assay utilized supported lipid bilayers that mimic the plasma membrane of apoptotic cells. The …


Small Molecule Disruption Of Ros-Regulating Pathways In Human Carcinoma, Rebecca E. Mccall Jan 2016

Small Molecule Disruption Of Ros-Regulating Pathways In Human Carcinoma, Rebecca E. Mccall

Electronic Theses and Dissertations

Gold (I) coordinated N-heterocyclic carbenes containing appended redox cycling moieties were designed and analyzed for their ability to target the antioxidant network via multiple mechanisms in various human cancer cell models. Complexes containing either ferrocene or naphthoquinone redox cycling moieties were screened for inhibition of cell growth, inhibition of thioredoxin reductase (TrxR), and accentuation of exogenous ROS. The cell death pathway employed was determined by flow cytometry via detection of Annexin-V FITC. Furthermore, differential gene expression between treated cells and untreated cells revealed the induction of endoplasmic reticulum stress and unfolded protein response pathways.