Life Sciences Commons^™

Characterization Of The Alternative Oxidase From The Psychrophilic Green Alga Chlamydomonas Sp. Uwo241, Michael Sj Inman

Electronic Thesis and Dissertation Repository

The alternative oxidase (AOX) was studied in the psychrophilic green alga Chlamydomonas sp. UWO241. AOX is the sole component of the alternative pathway of mitochondrial electron transport and is present in all plant and algal species. In silico analysis of the deduced protein sequence of the cloned AOX cDNA showed that the UWO241 protein has lower amounts of proline and higher amounts of lysine and tryptophan compared to the AOX sequence of the mesophilic alga C. reinhardtii. These changes have been seen in other studies of cold-adapted enzymes. Interestingly, unlike C. reinhardtii, AOX transcript abundance in UWO241 …

Molecular Evolution Of Protein-Rna Mimicry As A Mechanism For Translational Control, Assaf Katz, Lindsey Solden, S. Betty Zou, William Wiley Navarre, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a conserved ribosome-binding protein that structurally mimics tRNA to enable the synthesis of peptides containing motifs that otherwise would induce translational stalling, including polyproline. In many bacteria, EF-P function requires post-translational modification with (R)-β-lysine by the lysyl-tRNA synthetase paralog PoxA. To investigate how recognition of EF-P by PoxA evolved from tRNA recognition by aminoacyl-tRNA synthetases, we compared the roles of EF-P/PoxA polar contacts with analogous interactions in a closely related tRNA/synthetase complex. PoxA was found to recognize EF-P solely via identity elements in the acceptor loop, the domain of the protein that interacts with the …

The Role Of Choline Acetyltransferase Variants In Alzheimer's Disease Models, Shawn Albers

Electronic Thesis and Dissertation Repository

The primate specific 82-kDa choline acetyltransferase (ChAT) isoform is found in the nuclei of cholinergic neurons, with a disruption in the subcellular localization in aging and AD brain samples# The functional significance of this protein is poorly understood. Previous studies have revealed a potentially protective role for 82-kDa ChAT, mediated through a reduction in amyloid-!1-42 (A!1-42) release in APP/PS1 double transgenic primary cortical neurons. Here we examine the effect of 82-kDa ChAT expression in transgenic neurons, on the amyloidogenic processing of amyloid precursor protein (APP) and A! production. In this study we demonstrate 82-kDa ChAT transcriptionally increases golgi- localized "-ear-containing …

The Effect Of Testosterone On The Spring Migratory Phenotype Of A North American Songbird (Zonotrichia Albicollis), Caitlin L. Vandermeer

Electronic Thesis and Dissertation Repository

In passerines, the endocrine modulators responsible for seasonal changes in migratory behaviour and physiology are unclear. Spring photoperiods alter androgen levels, influencing muscle mass and fat deposition rates to power migration, as well as enhance nocturnal migratory restlessness activity (Zugunruhe). My study compared physiological indicators and migratory restlessness in castrated and intact white-throated sparrows (Zonotrichia albicollis) following photoperiod and hormone manipulation. Nocturnal restlessness activity was highest in migratory intact males or migratory castrated males that received testosterone replacement. Liver mass decreased in all photostimulated migratory groups regardless of testosterone treatment. Likewise, oxidative enzyme activity was unrelated to testosterone, …

Transforming Growth Factor-Beta Receptor Signalling Is Modulated By Integrin-Linked Kinase, Stellar H. Boo

Electronic Thesis and Dissertation Repository

Transforming growth factor-beta 1 (TGF-β1) modulates regeneration after injury through induction of fibroblast proliferation, migration, and differentiation into myofibroblasts. Induction of myofibroblast differentiation by TGF-β1 requires expression of integrin-linked kinase (ILK). I now show that ILK interacts with TGF-β receptor type II (TβRII) in primary dermal fibroblasts. Further, colocalization of ILK and TβRII can be observed at the cell membrane and in intracellular vesicles. The association of TβRII and ILK does not require TGF-β1 stimulation, kinase activity of TGF-β1 receptor type I or TβRII, and it does not involve interactions between ILK and focal adhesion-associated proteins. When this interaction is …

Leica Microscope Gpu Deconvolution Stellaris Fish Dataset #1, George Mcnamara

George McNamara

McNamara 20131101Fri Leica widefield microscope CUDA Deconvolution Stellaris FISH probe cultured cells dataset #1.zip

A text file in the zip archive has experiment details. I am posting this online so that researchers - whether academic or commercial - can evaluate the acquired data, the Bruce and Butte 2013 Optics Express ( http://www.opticsinfobase.org/oe/fulltext.cfm?uri=oe-21-4-4766 ) deconvolution result (note: I may not have used optimal settings), and to compare these deconvolution results to other methods. If anyone generates alternative spatial deconvolution output, such as from: * SVI Huygens * Media Cy AutoQuant * Agard's ER-Decon (Arigovindan 2013 PNAS) * Vicidomini SGP GPU Deconv …

Supervillin Binding To Myosin Ii And Synergism With Anillin Are Required For Cytokinesis, Tara C. Smith, Peter C. Fridy, Yinyin Li, Shruti Basil, Sneha Arjun, Ryan M. Friesen, John D. Leszyk, Brian T. Chait, Michael P. Rout, Elizabeth J. Luna

Elizabeth J. Luna

Cytokinesis, the process in which cytoplasm is apportioned between dividing daughter cells, requires coordination of myosin II function, membrane trafficking and central spindle organization. Most known regulators act during late cytokinesis; a few, including the myosin II-binding proteins anillin and supervillin, act earlier. Anillin's role in scaffolding the membrane cortex with the central spindle is well established, but the mechanism of supervillin action is relatively uncharacterized. We show here that two regions within supervillin affect cell division: residues 831-1281, which bind central spindle proteins, and residues 1-170, which bind the myosin II heavy chain (MHC) and the long form of …

Expression Analysis Of Histone Acetyltransferases In Rice Under Drought Stress, Hui Fang

Electronic Thesis and Dissertation Repository

Histone acetylation is one of the vital reversible modifications in eukaryotes. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) maintain the homeostasis of histone acetylation. HATs are associated with genome-wide transcriptional activation and various biological processes in response to various stresses. Drought stress causes a range of physiological and biochemical responses in plants. Eight HATs which belong to four different families (CBP, GNAT, MYST, and TAFII250 family) have been identified in rice. In this research, four OsHATs, one from each family, were chosen based on in silico domain and promoter analysis. The real-time qPCR analysis demonstrated that drought stress caused …

Acclimatization Of The Tropical Reef Coral Acropora Millepora To Hyperthermal Stress, Anthony John Bellantuono

FIU Electronic Theses and Dissertations

The demise of reef-building corals potentially lies on the horizon, given ongoing climate change amid other anthropogenic environmental stressors. If corals cannot acclimatize or adapt to changing conditions, dramatic declines in the extent and health of the living reefs are expected within the next half century. The primary and proximal global threat to corals is climate change. Reef-building corals are dependent upon a nutritional symbiosis with photosynthetic dinoflagellates belonging to the group Symbiodinium. The symbiosis between the cnidarian host and algal partner is a stress-sensitive relationship; temperatures just 1°C above normal thermal maxima can result in the breakdown of …

Aspirin And Low-Molecular Weight Heparin Combination Therapy Effectively Prevents Recurrent Miscarriage In Hyperhomocysteinemic Women., Pratip Chakraborty, Sayani Banerjee, Piyali Saha, Shyam Sundar Nandi, Sunita Sharma, Sourendra K. Goswami, Baidyanath Chakravarty, Syed N. Kabir

Journal Articles: Cellular & Integrative Physiology

The management of recurrent pregnancy loss (RPL) still remains a great challenge, and women with polycystic ovarian syndrome (PCOS) are at a greater risk for spontaneous abortion. Treatment with low-molecular-weight heparin (LMWH) has become an accepted treatment option for women with RPL; however, the subgroup of women, who are likely to respond to LMWH, has not been precisely identified. The present study evaluated the efficacy of LMWH with reference to PCOS and associated metabolic phenotypes including hyperhomocysteinemia (HHcy), insulin resistance (IR) and obesity. This prospective observational study was conducted at Institute of Reproductive Medicine, Kolkata, India. A total of 967 …

Dirigent Domain-Containing Protein Is Part Of The Machinery Required For Formation Of The Lignin-Based Casparian Strip In The Root, Prashant S. Hosmani, Takehiro Kamiya, John Danku, Sadaf Naseer, Niko Geldner, Mary Lou Guerinot, David Salt

Dartmouth Scholarship

The endodermis acts as a "second skin" in plant roots by providing the cellular control necessary for the selective entry of water and solutes into the vascular system. To enable such control, Casparian strips span the cell wall of adjacent endodermal cells to form a tight junction that blocks extracellular diffusion across the endodermis. This junction is composed of lignin that is polymerized by oxidative coupling of monolignols through the action of a NADPH oxidase and peroxidases. Casparian strip domain proteins (CASPs) correctly position this biosynthetic machinery by forming a protein scaffold in the plasma membrane at the site where …

Atrial Fibrillation-Linked Germline Gja5/Connexin40 Mutants Showed An Increased Hemichannel Function, Matthew D. Hills

Electronic Thesis and Dissertation Repository

Mutations in GJA5 encoding the gap junction protein connexin40 (Cx40) have been linked to lone atrial fibrillation (AF). Some of these mutants result in impaired gap junction function due to either abnormal connexin localization or impaired gap junction channels, which may play a role in promoting AF. However, the effects of the AF-linked Cx40 mutants on hemichannel function has not been studied. Here we investigated two AF-linked germline Cx40 mutants, V85I and L221I. These two mutants formed putative gap junction plaques at cell-cell interfaces, with similar gap junction coupling conductance as that of wild-type Cx40. Connexin deficient HeLa cells expressing …

Cyanobacteria Predominance In Alberta's Eutrophic Lakes Linked To Iron Scavenging Strategy That Uses Siderophores And Toxins, Xue L. Du

Electronic Thesis and Dissertation Repository

The role of the micronutrient iron in the regulation of cyanobacteria dominance and cyanotoxicity is poorly understood. Iron is required for important metabolic pathways, including both phosphorus (P) and nitrogen (N) assimilation, and low levels of this element may influence the assimilation of the macronutrients. The hypothesis tested was that cyanobacteria produce and utilize siderophores and toxins in low iron conditions to scavenge iron, when P and N are not limiting algal growth, providing some cyanobacteria with a competitive advantage over other algal species. Among the naturally eutrophic lakes studied, cyanobacteria were dominant at low iron (>pFe19) concentrations (Spearman …

Med13p Prevents Stress-Independent Mitochondrial Hyperfragmentation And Aberrant Apoptosis Activation In Saccharomyces Cerevisiae By Controlling Cyclin C Nuclear Localization, Svetlana Khakhina

Graduate School of Biomedical Sciences Theses and Dissertations

During aging, and as a result of environmental changes, cells are exposed to elevated levels of reactive oxygen species (ROS). High ROS levels induce lipid oxidation, protein aggregation, mitochondrial hyperfragmentation, DNA damage and programmed cell death (PCD), also called apoptosis. PCD is a highly regulated process and its misregulation has been linked to neurodegenerative diseases and cancer development.

Our hypothesis is that cyclin C plays a role in the initiation of apoptosis. During normal conditions, cyclin C represses the transcription of stress response genes (SRG). In response to stress, cyclin C translocates to the cytoplasm where it facilitates mitochondrial hyperfragmentation …

Skin Diseases And Non-Syndromic Hearing Loss Linked To Cx30 Mutations Arise Through Several Distinct Mechanisms, Amy C. Berger

Electronic Thesis and Dissertation Repository

Connexin 30 (Cx30), a member of the large gap junction protein family, plays a role in the homeostasis of the epidermis and inner ear through gap junctional intercellular communication (GJIC). Here, we investigated four autosomal dominant Cx30 gene mutations linked to hearing loss and/or various skin diseases. First, the T5M mutant linked to non-syndromic hearing loss formed functional gap junction channels and hemichannels, similar to wild-type Cx30. The V37E mutant associated with keratitis-ichthyosis-deafness (KID) syndrome was retained in the endoplasmic reticulum (ER) and significantly induced unfolded protein response (UPR)-mediated apoptosis. The loss-of-function G59R mutant linked to Vohwinkel and Bart-Pumphrey syndromes …

Direction Of Aminoacylated Transfer Rnas Into Antibiotic Synthesis And Peptidoglycan-Mediated Antibiotic Resistance, Jennifer Shepherd, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Prokaryotic aminoacylated‐transfer RNAs often need to be efficiently segregated between translation and other cellular biosynthetic pathways. Many clinically relevant bacteria, including Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa direct some aminoacylated‐tRNA species into peptidoglycan biosynthesis and/or membrane phospholipid modification. Subsequent indirect peptidoglycan cross‐linkage or change in membrane permeability is often a prerequisite for high‐level antibiotic resistance. In Streptomycetes, aminoacylated‐tRNA species are used for antibiotic synthesis as well as antibiotic resistance. The direction of coding aminoacylated‐tRNA molecules away from translation and into antibiotic resistance and synthesis pathways are discussed in this review.

Lipid Ii-Independent Trans Editing Of Mischarged Trnas By The Penicillin Resistance Factor Murm, Jennifer Shepherd, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Streptococcus pneumoniae is a causative agent of nosocomial infections such as pneumonia, meningitis, and septicemia. Penicillin resistance in S. pneumoniae depends in part upon MurM, an aminoacyl-tRNA ligase that attaches l-serine or l-alanine to the stem peptide lysine of Lipid II in cell wall peptidoglycan. To investigate the exact substrates the translation machinery provides MurM, quality control by alanyl-tRNA synthetase (AlaRS) was investigated. AlaRS mischarged serine and glycine to tRNAAla, as observed in other bacteria, and also transferred alanine, serine, and glycine to tRNA^Phe. S. pneumoniae tRNA^Phe has an unusual U4:C69 mismatch in its acceptor stem that …

Alcohol-Induced Il-1beta In The Brain Is Mediated By Nlrp3/Asc Inflammasome Activation That Amplifies Neuroinflammation, Dora Lippai, Shashi Bala, Jan Petrasek, Timea Csak, Ivan Levin, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Alcohol-induced neuroinflammation is mediated by proinflammatory cytokines, including IL-1beta. IL-1beta production requires caspase-1 activation by inflammasomes-multiprotein complexes that are assembled in response to danger signals. We hypothesized that alcohol-induced inflammasome activation contributes to increased IL-1beta in the brain. WT and TLR4-, NLRP3-, and ASC-deficient (KO) mice received an ethanol-containing or isocaloric control diet for 5 weeks, and some received the rIL-1ra, anakinra, or saline treatment. Inflammasome activation, proinflammatory cytokines, endotoxin, and HMGB1 were measured in the cerebellum. Expression of inflammasome components (NLRP1, NLRP3, ASC) and proinflammatory cytokines (TNF-alpha, MCP-1) was increased in brains of alcohol-fed compared with control mice. Increased …

Effect Of Shear Stress On Ecnos Expression And Dilation In Soleus Feed Arteries, Blanca Perez, Jay L. Brewster, Jeffrey Jasperse

Featured Research

Shear stress causes artery dilation and increased expression of endothelial cell nitric oxide synthase (ecNOS) in coronary and placental arteries. We sought to determine the importance of shear stress in maintaining normal dilation and normal levels of ecNOS in rat soleus feed arteries (SFA). SFA were isolated from male Sprague-Dawley rats and cannulated for in vitro microscopy (Fig. 6). SFA were exposed to no shear stress, low shear stress, or high shear stress conditions for 4 hours. After 4 hours, endothelium-dependent dilation (acetylcholine: ACh) and endothelium-independent dilation (sodium nitroprusside: SNP) were tested. Arteries were then uncannulated, mRNA was isolated, and …

Regulation Of Trpm2 Channels By Fyn Kinase, Matthew L. Johnston

Electronic Thesis and Dissertation Repository

TRPM2 is a calcium-permeable non-selective cation channel that acts as a mediator of cell death in response to oxidative stress. It has been shown that oxidative stress increases TRPM2 tyrosine phosphorylation and activation – an effect that is blocked by PP2, a non-specific inhibitor of Src family kinases. However, the kinase and target TRPM2 tyrosine residue(s) involved have not yet been identified. Here, we investigated the potential regulation of TRPM2 by Fyn. Intracellular application of recombinant Fyn potentiated TRPM2 currents in HEK293 cells expressing inducible TRPM2 (TRPM2-HEK293 cells). Further, a physical interaction between Fyn and TRPM2 was demonstrated by co-immunoprecipitation …

Modeling The Influence Of Vitamin D Deficiency On Cigarette Smoke-Induced Emphysema, Mardi A. Crane-Godreau, Candice C. Black, Andrew J. Giustini, Tenzin Dechen, Jihan Ryu, James A. Jukosky, Hong-Kee Lee, Katherine Bessette, Nora R. Ratcliffe, P. Jack Hoopes, Steven Fiering, John A. Kelly, J. C. Leiter

Dartmouth Scholarship

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. While the primary risk factor for COPD is cigarette smoke exposure, vitamin D deficiency has been epidemiologically implicated as a factor in the progressive development of COPD-associated emphysema. Because of difficulties inherent to studies involving multiple risk factors in the progression of COPD in humans, we developed a murine model in which to study the separate and combined effects of vitamin D deficiency and cigarette smoke exposure. During a 16-week period, mice were exposed to one of four conditions, control diet breathing room air (CD-NS), control …

A C-Terminus Mitochondrial-Localization Region And Bh3 Domain Of Puma Are Required For Apoptotic Function, Liz A. Merwin

Electronic Thesis and Dissertation Repository

Apoptosis is known to contribute to the loss of neurological function in brain injury and several neurodegenerative diseases. The Bcl-2 family of proteins consist of pro-apoptotic and anti-apoptotic members that interact physically and functionally to regulate apoptosis in a cell type and stimulus specific manner. We have previously demonstrated that the Bcl-2 family member Puma plays a key role in triggering neuronal apoptosis under diverse stress conditions. However, the mechanism by which Puma mediates apoptosis remains unclear. Here we found that Puma contains two domains required for its apoptotic function: the BH3 domain and a region in the c-terminus that …

Enabling Sum Frequency Spectroscopy And Fluorescence Correlation Spectroscopy Of Model Cellular Membranes, Sarah M. Sterling

Electronic Theses and Dissertations

The majority of proteins secreted from cells contain a signal peptide sequence that is required for secretion mediated by the endoplasmic reticulum and Golgi apparatus. However, many proteins lack the essential signal peptide sequence, yet still undergo secretion. Such proteins are known to regulate cell proliferation, differentiation, and migration. Fibroblast growth factor 1 (FGF-1) is one protein which undergoes non-classical protein transport. The role of its interactions with the cellular membrane during non-classical protein transport is not fully understood, although FGF-1 has shown preferential destabilizing effects on artificial membranes composed of acidic phospholipids. In the present work, physiologically relevant model …

A Literature Review Of Risk Factors For The Development Of Breast Cancer: Risks And Prevention Methods, Anna K. Manneschmidt

Chancellor’s Honors Program Projects

No abstract provided.

Nuclear Localization Of Cpi-17, A Protein Phosphatase-1 Inhibitor Protein, Affects Histone H3 Phosphorylation And Corresponds To Proliferation Of Cancer And Smooth Muscle Cells., Masumi Eto, Jason A Kirkbride, Rishika Chugh, Nana Kofi Karikari, Jee In Kim

Department of Molecular Physiology and Biophysics Faculty Papers

CPI-17 (C-kinase-activated protein phosphatase-1 (PP1) inhibitor, 17kDa) is a cytoplasmic protein predominantly expressed in mature smooth muscle (SM) that regulates the myosin-associated PP1 holoenzyme (MLCP). Here, we show CPI-17 expression in proliferating cells, such as pancreatic cancer and hyperplastic SM cells. Immunofluorescence showed that CPI-17 was concentrated in nuclei of human pancreatic cancer (Panc1) cells. Nuclear accumulation of CPI-17 was also detected in the proliferating vascular SM cell culture and cells at neointima of rat vascular injury model. The N-terminal 21-residue tail domain of CPI-17 was necessary for the nuclear localization. Phospho-mimetic Asp-substitution of CPI-17 at Ser12 attenuated the nuclear …

Divergent Protein Motifs Direct Ef-P Mediated Translational Regulation In Salmonella And Escherichia Coli, Steven J. Hersch, Mengchi Wang, S. Betty Zou, Kyung-Mee Moon, Leonard J. Foster, Michael Ibba, William Wiley Navarre

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a universally conserved bacterial translation factor homologous to eukaryotic/archaeal initiation factor 5A. In Salmonella, deletion of the efp gene results in pleiotropic phenotypes, including increased susceptibility to numerous cellular stressors. Only a limited number of proteins are affected by the loss of EF-P, and it has recently been determined that EF-P plays a critical role in rescuing ribosomes stalled at PPP and PPG peptide sequences. Here we present an unbiased in vivo investigation of the specific targets of EF-P by employing stable isotope labeling of amino acids in cell culture (SILAC) to compare the …

Flash4 Dark Reference Images, George Mcnamara

George McNamara

Hamamatsu FLASH4.0 dark reference images, acquired with 10 second exposure times, no light to camera. Camera offset (set by Hamamatsu( is ~100 (the average intensity of the first image is always ~1 intensity level higher - an odd feature, but trivial in practice for a 16-bit camera).

George McNamara, Ph.D.

Single Cells Analyst at L.J.N. Cooper Lab

University of Texas M.D. Anderson Cancer Center

Intrinsic Apoptotic Pathway: Effects Of Calcium On Murine Cytochrome C Release In Brain And Liver Mitochondria, Dane M. Edwards

Senior Honors Theses

A cell may use one of three main apoptotic pathways leading to programmed cell death: the extrinsic pathway, the perforin/granzyme pathway and the intrinsic pathway. The most pertinent to this discussion is the intrinsic pathway, which utilizes the mitochondria as an essential intermediary. Mitochondria’s primary function in relation to this pathway is the subsequent release of pro-apoptotic factors including cytochrome c, which activate a caspase cascade leading to the death of the cell. Cytochrome c is released partly due to an increase in cytosolic calcium levels. Two methods of the release of cytochrome c have been proposed. The first is …

Ectopic Mineralization Of Spinal Tissues In Mice Lacking Equilibrative Nucleoside Transporter 1, Sumeeta Warraich

Electronic Thesis and Dissertation Repository

Equilibrative nucleoside transporter 1 (ENT1) regulates the bi-directional transfer of hydrophilic nucleosides, such as adenosine, across the plasma membrane. Mice lacking ENT1 developed calcified lesions resembling diffuse idiopathic skeletal hyperostosis (DISH) in humans. By 12 months of age, ENT1^-/- mice exhibit spine stiffness, hind limb dysfunction, and paralysis. Histological examination of ENT1^-/- mice revealed irregular accumulations of eosinophilic material in paraspinal ligaments and entheses, intervertebral discs, and sternocostal articulations. There was no evidence of mineralization in appendicular joints or blood vessels. Analysis of intervertebral disc tissues of 6 month old ENT1^-/- and wild-type mice revealed reduced expression …

Elongation Factor 1a-1 And Hepatocyte Response To Fatty Acid Excess, Alexandra M. Stoianov

Electronic Thesis and Dissertation Repository

Obesity is associated with elevated levels of serum fatty acids, which accumulate in nonadipose tissues including the liver. Elongation factor 1A-1 (EF1A-1) has previously been shown to participate in the cell stress and death response of cardiomyocytes to excess saturated fatty exposure, and in steatotic mouse myocardium. In this thesis, the hypothesis that the hepatocyte response to fatty acid overload involves EF1A-1 was tested. EF1A-1 expression was induced in the livers of obese mice in association with severe hepatic steatosis, and in HepG2 human hepatoma cells in response to excess palmitate. Partial translocation of EF1A-1 from the ER to polymerized …