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2013

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Articles 31 - 60 of 274

Full-Text Articles in Cell and Developmental Biology

Regulation Of Stress-Inducible Phosphoprotein 1 Nuclear Retention By Protein Inhibitor Of Activated Stat Pias1, Iaci N. Soares, Fabiana A. Caetano, Jordan Pinder, Bruna Roz Rodrigues, Flavio H. Beraldo, Valeriy G. Ostapchenko, Chantal Durette, Grace Schenatto Pereira, Marilene H. Lopes, Nicolle Queiroz-Hazarbassanov, Isabela W. Cunha, Paulo I. Sanematsu, Sergio Suzuki, Luiz F. Bleggi-Torres, Caroline Schild-Poulter, Pierre Thibault, Graham Dellaire, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado Nov 2013

Regulation Of Stress-Inducible Phosphoprotein 1 Nuclear Retention By Protein Inhibitor Of Activated Stat Pias1, Iaci N. Soares, Fabiana A. Caetano, Jordan Pinder, Bruna Roz Rodrigues, Flavio H. Beraldo, Valeriy G. Ostapchenko, Chantal Durette, Grace Schenatto Pereira, Marilene H. Lopes, Nicolle Queiroz-Hazarbassanov, Isabela W. Cunha, Paulo I. Sanematsu, Sergio Suzuki, Luiz F. Bleggi-Torres, Caroline Schild-Poulter, Pierre Thibault, Graham Dellaire, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado

Anatomy and Cell Biology Publications

Stress-inducible phosphoprotein 1 (STI1), a cochaperone for Hsp90, has been shown to regulate multiple pathways in astrocytes, but its contributions to cellular stress responses are not fully understood. We show that in response to irradiation-mediated DNA damage stress STI1 accumulates in the nucleus of astrocytes. Also, STI1 haploinsufficiency decreases astrocyte survival after irradiation. Using yeast two-hybrid screenings we identified several nuclear proteins as STI1 interactors. Overexpression of one of these interactors, PIAS1, seems to be specifically involved in STI1 nuclear retention and in directing STI1 and Hsp90 to specific sub-nuclear regions. PIAS1 and STI1 co-immunoprecipitate and PIAS1 can function as …

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Reflections On The Cost Of "Low-Cost" Whole Genome Sequencing: Framing The Health Policy Debate, Timothy Caulfield, Jim Evans, Amy Mcguire, Christopher Mccabe, Tania M. Bubela, Robert Cook-Deegan, Jennifer Fishman, Stuart Hogarth, Fiona A. Miller, Vardit Ravitsky Nov 2013

Reflections On The Cost Of "Low-Cost" Whole Genome Sequencing: Framing The Health Policy Debate, Timothy Caulfield, Jim Evans, Amy Mcguire, Christopher Mccabe, Tania M. Bubela, Robert Cook-Deegan, Jennifer Fishman, Stuart Hogarth, Fiona A. Miller, Vardit Ravitsky

Office of the Provost

The cost of whole genome sequencing is dropping rapidly. There has been a great deal of enthusiasm about the potential for this technological advance to transform clinical care. Given the interest and significant investment in genomics, this seems an ideal time to consider what the evidence tells us about potential benefits and harms, particularly in the context of health care policy. The scale and pace of adoption of this powerful new technology should be driven by clinical need, clinical evidence, and a commitment to put patients at the centre of health care policy.

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Prenatal Development: Annotated Bibliography, Victoria J. Molfese, Amanda Prokasky, Kathleen Moritz Rudasill, Ibrahim H. Acar, Xiaoqing Tu, Kate Sirota, Brian Keiser Nov 2013

Prenatal Development: Annotated Bibliography, Victoria J. Molfese, Amanda Prokasky, Kathleen Moritz Rudasill, Ibrahim H. Acar, Xiaoqing Tu, Kate Sirota, Brian Keiser

Department of Child, Youth, and Family Studies: Faculty Publications

For decades, researchers have investigated how events in the prenatal period impact women and their infants. These studies, particularly by researchers in the medical, neuroscience, and behavioral science fields, led to discoveries of important information regarding the prenatal events that were strongly associated with mortality (or death) and morbidity (or incidences of injury, pathology and abnormalities/anomalies, and neurobehavioral sequelae) in the neonatal and infancy periods. Among the many common findings from early research studies, two are particularly noteworthy. First, maternal and fetal risk conditions arising in the prenatal period do not do so in isolation. Sameroff and Chandler characterized this …

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Identification And Rna Binding Characterization Of Plant Virus Rna Silencing Suppressor Proteins, Jeff Vargason, Carissa J. Burch, Jesse W. Wilson Nov 2013

Identification And Rna Binding Characterization Of Plant Virus Rna Silencing Suppressor Proteins, Jeff Vargason, Carissa J. Burch, Jesse W. Wilson

Faculty Publications - Department of Biological & Molecular Science

Suppression is a common mechanism employed by viruses to evade the antiviral effects of the host’s RNA silencing pathway. The activity of suppression has commonly been localized to gene products in the virus, but the variety of mechanisms used in suppression by these viral proteins spans nearly the complete biochemical pathway of RNA silencing in the host. This review describes the agrofiltration assay and a slightly modified version of the agro-infiltration assay called co-infiltration, which are common methods used to observe RNA silencing and identify viral silencing suppressor proteins in plants, respectively. In addition, this review will provide an overview …

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Novel Neuroprotective Function Of Apical-Basal Polarity Genecrumbs In Amyloid Beta 42 (Aβ42) Mediated Neurodegeneration, Andrew Steffensmeier, Meghana Tare, Oorvashi Roy Puli, Rohan Modi, Jaison Nainaparampil, Madhuri Kango-Singh, Amit Singh Nov 2013

Novel Neuroprotective Function Of Apical-Basal Polarity Genecrumbs In Amyloid Beta 42 (Aβ42) Mediated Neurodegeneration, Andrew Steffensmeier, Meghana Tare, Oorvashi Roy Puli, Rohan Modi, Jaison Nainaparampil, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

Alzheimer's disease (AD, OMIM: 104300), a progressive neurodegenerative disorder with no cure to date, is caused by the generation of amyloid-beta-42 (Aβ42) aggregates that trigger neuronal cell death by unknown mechanism(s). We have developed a transgenic Drosophilaeye model where misexpression of human Aβ42 results in AD-like neuropathology in the neural retina. We have identified an apical-basal polarity gene crumbs (crb) as a genetic modifier of Aβ42-mediated-neuropathology. Misexpression of Aβ42 caused upregulation of Crb expression, whereas downregulation of Crb either by RNAi or null allele approach rescued the Aβ42-mediated-neurodegeneration. Co-expression of full length Crb with Aβ42 increased severity of Aβ42-mediated-neurodegeneration, …

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Killerflip: A Novel Lytic Peptide Specifically Inducing Cancer Cell Death, B Pennarun, G. Gaidos, O Bucur, A Tinari Oct 2013

Killerflip: A Novel Lytic Peptide Specifically Inducing Cancer Cell Death, B Pennarun, G. Gaidos, O Bucur, A Tinari

Dartmouth Scholarship

One of the objectives in the development of effective cancer therapy is induction of tumor-selective cell death. Toward this end, we have identified a small peptide that, when introduced into cells via a TAT cell-delivery system, shows a remarkably potent cytoxicity in a variety of cancer cell lines and inhibits tumor growth in vivo, whereas sparing normal cells and tissues. This fusion peptide was named killer FLIP as its sequence was derived from the C-terminal domain of c-FLIP, an anti-apoptotic protein. Using structure activity analysis, we determined the minimal bioactive core of killerFLIP, namely killerFLIP-E. Structural analysis of cells using …

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Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D. Oct 2013

Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Middle Eastern Respiratory Syndrome (MERS) is an emerging viral disease originating in the Arabian Peninsula with a current mortality rate of nearly fifty percent throughout Europe and Asia according to the World Health Organization. Characterization of this disease is being done to understand the basis of viral replication. One target for viral inhibition are replication proteases. Replication proteases are enzymes that cleave proteins specific to cell growth and reproduction that form the viral replicase complex making them an ideal target for viral replication inhibition. First, replication proteases were characterized using a fluorescence resonance energy transfer (FRET) construct by measuring the …

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Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs Oct 2013

Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Set1 complex, a histone methyltransferase complex found in S. cerevisiae (budding yeast), is the only histone methyltransferase responsible for catalyzing methylation of histone H3 at Lysine 4. It possesses homologues in other species, humans included. While yeast only have the Set1 complex, the human homologues of the yeast Set1 complex include mixed-lineage leukemia family (MLL1-4), Set1 A, Set1 B, among others. MLL1-4 has been shown to play a role in transcription, cell type specification, and the development of leukemia. One application of characterizing the role of a protein is that the information gained can provide insight into the function …

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Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao Oct 2013

Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Engineering synthetic multicellular systems will lead to new synthetic biology technological platforms, inform developmental biology through recapitulation of natural systems and possibly unveil novel morphologies with practical applications not before reached throughout natural history (Maharbiz, 2012). Creating an exogenous molecular circuit that will polarize unicellular cells into “apical” and “basal” domains relative to a substrate plane would fulfill a missing component towards fully multicellular synthetic cellular communities (Maharbiz, 2012). To this end, a PIP3 polarization network previously designed by Chau and associates (Chau, Walter, Gerardin, Tang, Lim 2012) was coupled to the specific activation by niacin of a recombinant …

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In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud, James T. Mccarthy, Andrew Schilb, Sarah Calve Oct 2013

In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud, James T. Mccarthy, Andrew Schilb, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

The extracellular matrix (ECM) is composed of many different proteins excreted by cells and is believed to play a very important role in development as well as regeneration and wound healing. In this research, a method to determine the ECM’s effect on the migration of muscle progenitor cells into the mammalian limb bud was investigated. It has traditionally been difficult to obtain in vivo images of the limb bud, due to the difficulty of maintaining embryos in culture and limitations of imaging techniques. In this study, we have worked on optimizing the culture conditions to allow growth of mouse embryos …

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Hair-Cell-Specific Genes In The Embryonic Chicken Inner Ear By Overexpression, Eric S. Traub, Donna Fekete Oct 2013

Hair-Cell-Specific Genes In The Embryonic Chicken Inner Ear By Overexpression, Eric S. Traub, Donna Fekete

The Summer Undergraduate Research Fellowship (SURF) Symposium

The inner ear houses organs used for hearing and balance that use hair cells to accomplish their tasks. Inner ear development remains to be fully understood, and advancing knowledge in development could lead to therapies and treatments for hearing problems. A gene called Atoh1 is necessary for hair cell formation and has been shown to increase hair cell number when overexpressed. Importantly, microRNAs from the 183 family (miRs-183, -182, and -96) are also expressed in developing hair cells. MicroRNAs are small RNA molecules that bind to messenger RNAs and prevent translation. MicroRNAs have been associated with cellular functions such as …

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The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve Oct 2013

The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

To improve the treatment of musculoskeletal injuries, a better understanding of the transitional environment in which progenitor cells form mature musculoskeletal constructs is necessary. This need arises because injury repair requires restructuring of tissue, similar to the initial tissue construction that occurs during embryonic development by progenitor cells. Differences in both the biochemical and mechanical environments between a transitional and a differentiated state are known to take place, but how these differences affect cell behavior had not yet been characterized in mammalian tendon cells. In order to investigate this, we have determined the effects of exogenous extracellular matrix and the …

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The Prion Protein Ligand, Stress-Inducible Phosphoprotein 1, Regulates Amyloid-Beta Oligomer Toxicity, Valeriy G. Ostapchenko, Flavio H. Beraldo, Amro H. Mohammad, Yu-Feng Xie, Pedro H. F. Hirata, Ana C. Magalhaes, Guillaume Lamour, Hongbin Li, Andrzej Maciejewski, Jillian C. Belrose, Bianca L. Teixeira, Margaret Fahnestock, Sergio T. Ferreira, Neil R. Cashman, Glaucia N. M. Hajj, Michael F. Jackson, Wing-Yiu Choy, John F. Macdonald, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado Oct 2013

The Prion Protein Ligand, Stress-Inducible Phosphoprotein 1, Regulates Amyloid-Beta Oligomer Toxicity, Valeriy G. Ostapchenko, Flavio H. Beraldo, Amro H. Mohammad, Yu-Feng Xie, Pedro H. F. Hirata, Ana C. Magalhaes, Guillaume Lamour, Hongbin Li, Andrzej Maciejewski, Jillian C. Belrose, Bianca L. Teixeira, Margaret Fahnestock, Sergio T. Ferreira, Neil R. Cashman, Glaucia N. M. Hajj, Michael F. Jackson, Wing-Yiu Choy, John F. Macdonald, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado

Anatomy and Cell Biology Publications

In Alzheimer's disease (AD), soluble amyloid-beta oligomers (A beta Os) trigger neurotoxic signaling, at least partially, via the cellular prion protein (PrPC). However, it is unknown whether other ligands of PrPC can regulate this potentially toxic interaction. Stress-inducible phosphoprotein 1 (STI1), an Hsp90 cochaperone secreted by astrocytes, binds to PrPC in the vicinity of the A beta O binding site to protect neurons against toxic stimuli. Here, we investigated a potential role of STI1 in A beta O toxicity. We confirmed the specific binding of A beta Os and STI1 to the PrP and showed that STI1 efficiently inhibited A …

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Endogenous Human Mdm2-C Is Highly Expressed In Human Cancers And Functions As A P53-Independent Growth Activator, Danielle R. Okoro, Nicoleta Arva, Chong Gao, Alla Polotskaia, Cindy Puente, Melissa Rosso, Jill Bargonetti Oct 2013

Endogenous Human Mdm2-C Is Highly Expressed In Human Cancers And Functions As A P53-Independent Growth Activator, Danielle R. Okoro, Nicoleta Arva, Chong Gao, Alla Polotskaia, Cindy Puente, Melissa Rosso, Jill Bargonetti

Publications and Research

Human cancers over-expressing mdm2, through a T to G variation at a single nucleotide polymorphism at position 309 (mdm2 SNP309), have functionally inactivated p53 that is not effectively degraded. They also have high expression of the alternatively spliced transcript, mdm2-C. Alternatively spliced mdm2 transcripts are expressed in many forms of human cancer and when they are exogenously expressed they transform human cells. However no study to date has detected endogenous MDM2 protein isoforms. Studies with exogenous expression of splice variants have been carried out with mdm2-A and mdm2-B, but the mdm2-C isoform has remained virtually unexplored. We addressed the cellular …

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The Mechanism Of The Gastric Epithelial Stem Cell Response To Metaplastic Injury, Shradha Sachin Khurana Oct 2013

The Mechanism Of The Gastric Epithelial Stem Cell Response To Metaplastic Injury, Shradha Sachin Khurana

All Theses and Dissertations (ETDs)

Almost nothing is known about the identity of the epithelial stem cell of the gastric corpus, either during normal turnover or in response to injury. Our lab has shown that injection of the selective estrogen receptor modulator tamoxifen leads to near complete atrophy of parietal cells by 3 days and induces expansion of an undifferentiated cell population within the normal stem cell niche in the isthmus of the gastric unit. Here we show that CD44 labels the membranes of such undifferentiated isthmal cells, both in the normal gastric epithelium and when those cells expand fourfold upon injury with tamoxifen. Loss …

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Development Of A Conditional Mesd (Mesoderm Development) Allele For Functional Analysis Of The Low-Density Lipoprotein Receptor-Related Family In Defined Tissues, Andrew V. Taibi, Janet K. Lighthouse, Richard C. Grady, Kenneth R. Shroyer, Bernadette Holdener Oct 2013

Development Of A Conditional Mesd (Mesoderm Development) Allele For Functional Analysis Of The Low-Density Lipoprotein Receptor-Related Family In Defined Tissues, Andrew V. Taibi, Janet K. Lighthouse, Richard C. Grady, Kenneth R. Shroyer, Bernadette Holdener

Department of Biomedical Engineering Faculty Publications

The Low-density lipoprotein receptor-Related Protein (LRP) family members are essential for diverse processes ranging from the regulation of gastrulation to the modulation of lipid homeostasis. Receptors in this family bind and internalize a diverse array of ligands in the extracellular matrix (ECM). As a consequence, LRPs regulate a wide variety of cellular functions including, but not limited to lipid metabolism, membrane composition, cell motility, and cell signaling. Not surprisingly, mutations in single human LRPs are associated with defects in cholesterol metabolism and development of atherosclerosis, abnormalities in bone density, or aberrant eye vasculature, and may be a contributing factor in …

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Bacterial Transcription Factors Grea, Greb And Dksa: Characterization Of Their Interaction With Rna Polymerase And Molecular Mechanism Of Action, Andrey Parshin Oct 2013

Bacterial Transcription Factors Grea, Greb And Dksa: Characterization Of Their Interaction With Rna Polymerase And Molecular Mechanism Of Action, Andrey Parshin

Graduate School of Biomedical Sciences Theses and Dissertations

The activity of RNA polymerase (RNAP), the key enzyme of transcription process, is regulated by a large number of transcription factors acting at each step of the transcription cycle. Our research project is focused on studying the structure and function of bacterial transcript cleavage factors GreA, GreB and the stringent response regulator DksA. Gre factors bind in the secondary channel of RNAP in backtracked (inactive) ternary elongation complexes and stimulate the enzyme's intrinsic RNase activity, which is required for suppression of transcription pause and arrest, enhancement of transcription fidelity, and efficient promoter escape. DksA also acts through the RNAP secondary …

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Synthesis And Antiproliferative Activities Of Quebecol And Its Analogs, Kasiviswanadharaju Pericherla, Amir Nasrolahi Shirazi, V. Kameshwara Rao, Rakesh Tiwari, Nicholas Dasilva, Kellen Mccaffrey, Yousef A. Beni, Antonio González- Sarrías, Navindra P. Seeram, Keykavous Parang, Anil Kumar Oct 2013

Synthesis And Antiproliferative Activities Of Quebecol And Its Analogs, Kasiviswanadharaju Pericherla, Amir Nasrolahi Shirazi, V. Kameshwara Rao, Rakesh Tiwari, Nicholas Dasilva, Kellen Mccaffrey, Yousef A. Beni, Antonio González- Sarrías, Navindra P. Seeram, Keykavous Parang, Anil Kumar

Pharmacy Faculty Articles and Research

Simple and efficient synthesis of quebecol and a number of its analogs was accomplished in five steps. The synthesized compounds were evaluated for antiproliferative activities against human cervix adenocarcinoma (HeLa), human ovarian carcinoma (SK-OV-3), human colon carcinoma (HT-29), and human breast adenocarcinoma (MCF-7) cancer cell lines. Among all the compounds, 7c, 7d, 7f, and 8f exhibited antiproliferative activities against four tested cell lines with inhibition over 80% at 75 mu M after 72 h, whereas, compound 7b and 7g were more selective towards MCF-7 cell line. The IC50 values for compounds 7c, 7d, and 7f were 85.1 mu M, 78.7 …

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Establishing The Role Of The Pancreatic Transcription Factor Mist1 In Xbp1-Mediated Maintenance Of Pancreatic Acinar Cell Homeostasis, David Alan Hess Oct 2013

Establishing The Role Of The Pancreatic Transcription Factor Mist1 In Xbp1-Mediated Maintenance Of Pancreatic Acinar Cell Homeostasis, David Alan Hess

Open Access Dissertations

Pancreatic acinar cells (PACs) continuously produce more protein than any other cell type in the human body. As a result, PACs and other specialized secretory cells have a constant demand placed on their protein synthetic and packaging machinery. When demand for secreted products exceeds the capacity of the cell's basal protein production facilities, dangerous accumulations of misfolded proteins can build up, resulting in a condition known as ER stress. To ameliorate this stress, secretory cells activate a coordinated, three-part compensatory network collectively known as the unfolded protein response (UPR) to both expand the capacity of the ER and directly assist …

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Measuring And Modeling The Response Characteristics Of The Environmental Phosphate Transducer In Escherichia Coli, Chetan Sood Oct 2013

Measuring And Modeling The Response Characteristics Of The Environmental Phosphate Transducer In Escherichia Coli, Chetan Sood

Open Access Dissertations

The PhoR/PhoB two-component system in Escherichia coli is a biological transducer that senses the limitation of environmental inorganic orthophosphate, the bacteria's preferred source of the essential nutrient phosphate, and transmits that information to the interior of the cell initiating a response that mitigates phosphate starvation. In the first part of this study, we present and apply a fluorescence microscopy technique to measure, in vivo, the dynamic response characteristics of the transducer with single-cell resolution. We report that the transience in the PhoR/PhoB TCS response is consistent with the transducer having a threshold sensitivity to the concentration of environmental phosphate, …

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Small Molecule Antagonists Of Melanopsin-Mediated Phototransduction, Kenneth A. Jones, Megumi Hatori, Ludovic S. Mure, Jayne R. Bramley, Roman Artymyshyn, Sang-Phyo Hong, Mohammad Marzabadi, Huailing Zhong, Jeffrey Sprouse, Quansheng Zhu, Andrew T. E. Hartwick, Patricia J. Sollars, Gary E. Pickard, Satchidananda Panda Oct 2013

Small Molecule Antagonists Of Melanopsin-Mediated Phototransduction, Kenneth A. Jones, Megumi Hatori, Ludovic S. Mure, Jayne R. Bramley, Roman Artymyshyn, Sang-Phyo Hong, Mohammad Marzabadi, Huailing Zhong, Jeffrey Sprouse, Quansheng Zhu, Andrew T. E. Hartwick, Patricia J. Sollars, Gary E. Pickard, Satchidananda Panda

School of Veterinary and Biomedical Sciences: Faculty Publications

Melanopsin, expressed in a subset of retinal ganglion cells, mediates behavioral adaptation to ambient light and other non-image forming photic responses. This has raised the possibility that pharmacological manipulation of melanopsin can modulate several CNS responses including photophobia, sleep, circadian rhythms and neuroendocrine function. Here we describe the identification of a potent synthetic melanopsin antagonist with in vivo activity. Novel sulfonamide compounds inhibiting melanopsin (opsinamides) compete with retinal binding to melanopsin and inhibit its function without affecting rod/cone mediated responses. In vivo administration of opsinamides to mice specifically and reversibly modified melanopsin-dependent light responses including the pupillary light reflex and …

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Protein Kinase Ck2 Phosphorylates And Activates P21-Activated Kinase 1, Yong Jae Shin, Yong-Bae Kim, Jeong-Ho Kim Sep 2013

Protein Kinase Ck2 Phosphorylates And Activates P21-Activated Kinase 1, Yong Jae Shin, Yong-Bae Kim, Jeong-Ho Kim

Biochemistry and Molecular Medicine Faculty Publications

Activation of the p21-activated kinase 1 (PAK1) is achieved through a conformational change that converts an inactive PAK1 dimer to an active monomer. In this paper, we show that this change is necessary but not sufficient to activate PAK1 and that it is, rather, required for CK2-dependent PAK1S223 phosphorylation that converts a monomeric PAK1 into a catalytically active form. This phosphorylation appears to be essential for autophosphorylation at specific residues and overall activity of PAK1. A phosphomimetic mutation (S223E) bypasses the requirement for GTPases in PAK1 activation, whereas the constitutive activity of the PAK1 mutant (PAK1H83,86L), postulated to mimic GTPase-induced …

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Identification Of Proteins Potentially Involved In The Formation Of Lafora Bodies, A Hallmark Of Lafora Disease, Elham Schokraie, Oliver Kötting, Matthew S. Gentry Sep 2013

Identification Of Proteins Potentially Involved In The Formation Of Lafora Bodies, A Hallmark Of Lafora Disease, Elham Schokraie, Oliver Kötting, Matthew S. Gentry

Molecular and Cellular Biochemistry Presentations

Lafora Disease (LD) is a fatal teenage-onset progressive myoclonus epilepsy. It is characterized by the formation of Lafora bodies (LBs), deposits of abnormally branched, insoluble, hyperphosphorylated glycogen-like polymers that are generally believed to trigger the development of the clinical symptoms of LD. 58% and 35% of the LD cases are caused by mutations in EPM2A (laforin) and EPM2B (malin), respectively. However, little is known about their function in LB formation. Two different mechanisms have been proposed to explain the accumulation of insoluble LBs: first, excessive glycogen phosphorylation and, second, an imbalance between glycogen synthesizing enzymes. The present study aims at …

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Forebrain Deletion Of The Vesicular Acetylcholine Transporter Results In Deficits In Executive Function, Metabolic, And Rna Splicing Abnormalities In The Prefrontal Cortex, Benjamin Kolisnyk, Mohammed A. Al-Onaizi, Pedro H. F. Hirata, Monica S. Guzman, Simona Nikolova, Shahar Barbash, Hermona Soreq, Robert Bartha, Marco A. M. Prado, Vania F. Prado Sep 2013

Forebrain Deletion Of The Vesicular Acetylcholine Transporter Results In Deficits In Executive Function, Metabolic, And Rna Splicing Abnormalities In The Prefrontal Cortex, Benjamin Kolisnyk, Mohammed A. Al-Onaizi, Pedro H. F. Hirata, Monica S. Guzman, Simona Nikolova, Shahar Barbash, Hermona Soreq, Robert Bartha, Marco A. M. Prado, Vania F. Prado

Anatomy and Cell Biology Publications

One of the key brain regions in cognitive processing and executive function is the prefrontal cortex (PFC), which receives cholinergic input from basal forebrain cholinergic neurons. We evaluated the contribution of synaptically released acetylcholine (ACh) to executive function by genetically targeting the vesicular acetylcholine transporter (VAChT) in the mouse forebrain. Executive function was assessed using a pairwise visual discrimination paradigm and the 5-choice serial reaction time task (5-CSRT). In the pairwise test, VAChT-deficient mice were able to learn, but were impaired in reversal learning, suggesting that these mice present cognitive inflexibility. Interestingly, VAChT-targeted mice took longer to reach criteria in …

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Centrosomal Kinase Nek2 Cooperates With Oncogenic Pathways To Promote Metastasis, T K. Das, Dibyendu Dana, Suneeta S. Paroly, S. K. Perumal, S. Singh, H. Jhun, J. Pendse, R. L. Cagan, T. T. Talele, Sanjai Kumar Sep 2013

Centrosomal Kinase Nek2 Cooperates With Oncogenic Pathways To Promote Metastasis, T K. Das, Dibyendu Dana, Suneeta S. Paroly, S. K. Perumal, S. Singh, H. Jhun, J. Pendse, R. L. Cagan, T. T. Talele, Sanjai Kumar

Publications and Research

Centrosomal kinase Nek2 is overexpressed in different cancers, yet how it contributes toward tumorigenesis remains poorly understood. dNek2 overexpression in a Drosophila melanogaster model led to upregulation of Drosophila Wnt ortholog wingless (Wg), and alteration of cell migration markers—Rho1, Rac1 and E-cadherin (Ecad)—resulting in changes in cell shape and tissue morphogenesis. dNek2 overexpression cooperated with receptor tyrosine kinase and mitogen-activated protein kinase signaling to upregulate activated Akt, Diap1, Mmp1 and Wg protein to promote local invasion, distant seeding and metastasis. In tumor cell injection assays, dNek2 cooperated with Ras and Src signaling to promote aggressive colonization of tumors into different …

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Exploring New Chemotherapeutic Strategies Against Brain Cancer, Seol Kim, Anthony J. Berdis Sep 2013

Exploring New Chemotherapeutic Strategies Against Brain Cancer, Seol Kim, Anthony J. Berdis

Undergraduate Research Posters 2013

Approximately 4,000 children in the United States are diagnosed each year with a brain tumor. Brain cancers are the deadliest of all pediatric cancers as they have survival rates of less than 20%. Typical treatments include surgery and radiation therapy. However, chemotherapy is the primary therapeutic option for children, especially against aggressive brain tumors. An important chemotherapeutic agent is temozolomide, an alkylating agent that causes cell death by damaging DNA. In this project, we tested the ability of non-natural nucleosides developed in our lab in order to increase the ability of temozolomide to kill brain cancer cells. Our results show …

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Function Of A Novel Checkpoint Protein In The Germ Line, Steven Drellishak, Marina Bykova, G. Valentin Börner Sep 2013

Function Of A Novel Checkpoint Protein In The Germ Line, Steven Drellishak, Marina Bykova, G. Valentin Börner

Undergraduate Research Posters 2013

Successful reproduction of Saccharomyces cerevisiae relies on the organism’s ability to complete the meiotic cell cycle and produce viable gametes. Zip1 is a protein that constitutes the central component of a protein structure that connects homologous chromosomes known as the synaptonemal complex. Zip1 is important for progression through the meiotic cell cycle. The C terminus of the coiled-coil Zip 1 protein is responsible for localization to the axes of the chromosomes. An internal deletion near the C terminus of Zip1, called zip1-c1, yields a stronger meiotic arrest than a mutation where Zip1 is completely deleted. The more efficient meiotic progression …

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Effects Of Butyltins On Mitogen-Activated-Protein Kinase Kinase Kinase And Ras Activity In Human Natural Killer Cells, Lindsay J. Celada, Margaret M. Whalen Sep 2013

Effects Of Butyltins On Mitogen-Activated-Protein Kinase Kinase Kinase And Ras Activity In Human Natural Killer Cells, Lindsay J. Celada, Margaret M. Whalen

Chemistry Faculty Research

Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT) diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The …

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Pseudomonas Aeruginosa Exotoxin Y-Mediated Tau Hyperphosphorylation Impairs Microtubule Assembly In Pulmonary Microvascular Endothelial Cells, Ron Balczon, Nutan Prasain, Cristhiaan Ochoa, Jason Prater, Bing Zhu, Mikhail Alexeyev, Sarah Sayner, Dara W. Frank, Troy Stevens Sep 2013

Pseudomonas Aeruginosa Exotoxin Y-Mediated Tau Hyperphosphorylation Impairs Microtubule Assembly In Pulmonary Microvascular Endothelial Cells, Ron Balczon, Nutan Prasain, Cristhiaan Ochoa, Jason Prater, Bing Zhu, Mikhail Alexeyev, Sarah Sayner, Dara W. Frank, Troy Stevens

University Faculty and Staff Publications

Pseudomonas aeruginosa uses a type III secretion system to introduce the adenylyl and guanylyl cyclase exotoxin Y (ExoY) into the cytoplasm of endothelial cells. ExoY induces Tau hyperphosphorylation and insolubility, microtubule breakdown, barrier disruption and edema, although the mechanism(s) responsible for microtubule breakdown remain poorly understood. Here we investigated both microtubule behavior and centrosome activity to test the hypothesis that ExoY disrupts microtubule dynamics. Fluorescence microscopy determined that infected pulmonary microvascular endothelial cells contained fewer microtubules than control cells, and further studies demonstrated that the microtubule-associated protein Tau was hyperphosphorylated following infection and dissociated from microtubules. Disassembly/reassembly studies determined that …

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Resistance Of Human Cytomegalovirus To Cyclopropavir Maps To A Base Pair Deletion In The Open Reading Frame Of Ul97, Brian G. Gentry, Laura E. Vollmer, Ellie D. Hall, Katherine Z. Borysko, Jiri Zemlicka, Jeremy P. Kamil, John C. Drach Sep 2013

Resistance Of Human Cytomegalovirus To Cyclopropavir Maps To A Base Pair Deletion In The Open Reading Frame Of Ul97, Brian G. Gentry, Laura E. Vollmer, Ellie D. Hall, Katherine Z. Borysko, Jiri Zemlicka, Jeremy P. Kamil, John C. Drach

Oncology Faculty Publications

Human cytomegalovirus (HCMV) is a widespread pathogen in the human population, affecting many immunologically immature and immunocompromised patients, and can result in severe complications, such as interstitial pneumonia and mental retardation. Current chemotherapies for the treatment of HCMV infections include ganciclovir (GCV), foscarnet, and cidofovir. However, the high incidences of adverse effects (neutropenia and nephrotoxicity) limit the use of these drugs. Cyclopropavir (CPV), a guanosine nucleoside analog, is 10-fold more active against HCMV than GCV (50% effective concentrations [EC50s] = 0.46 and 4.1 μM, respectively). We hypothesize that the mechanism of action of CPV is similar to that …

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