Molecular Biology Commons^™

Myod Targets Chromatin Remodeling Complexes To The Myogenin Locus Prior To Forming A Stable Dna-Bound Complex, Ivana L. De La Serna, Yasuyuki Ohkawa, Charlotte A. Berkes, Donald A. Bergstrom, Caroline S. Dacwag, Stephen J. Tapscott Fred Hutchinson Cancer Research Center, Anthony N. Imbalzano

Biology Faculty Publications

The activation of muscle-specific gene expression requires the coordinated action of muscle regulatory proteins and chromatin-remodeling enzymes. Microarray analysis performed in the presence or absence of a dominant-negative BRG1 ATPase demonstrated that approximately one-third of MyoD-induced genes were highly dependent on SWI/SNF enzymes. To understand the mechanism of activation, we performed chromatin immunoprecipitations analyzing the myogenin promoter. We found that H4 hyperacetylation preceded Brg1 binding in a MyoD-dependent manner but that MyoD binding occurred subsequent to H4 modification and Brg1 interaction. In the absence of functional SWI/SNF enzymes, muscle regulatory proteins did not bind to the myogenin promoter, thereby providing …

The Effect Of Rooibos Tea (Aspalathus Linearis) On The Survival And Transformation Of C3h-Bt1 Mouse Fibroblasts, Krista M. Beach, Paul J. Smith

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Defensin In The Ticks Dermacentor Variabilis And Ixodes Scapularis, Shane Michael Ceraul

Theses and Dissertations in Biomedical Sciences

This dissertation presents the identification, molecular structure and expression of defensin, an antimicrobial peptide, in the ticks, Dermacentor variabilis and Ixodes scapularis. A 624 bp cDNA molecule for defensin was cloned and sequenced from hemocytes, fat body and midgut of unstimulated D. variabilis ticks. Defensin peptide was detected only in the hemocyte lysates. These results suggest that the defensin from D. variabilis is synthesized and stored in the hemocytes, although the role of other tissues is not excluded.

The ability of the juvenile stage ticks to express the defensin gene was confirmed. Detection of the defensin transcript in all …

The Antitumor Agent, Arglabin-Dma, Preferentially Induces Apoptosis In Human Colon Tumor Cells, Sung Wook Kwon

Theses and Dissertations in Biomedical Sciences

Arglabin-DMA, an analog of farnesyl pyrophosphate (FPP), reportedly inhibits farnesyltransferase (FTase) directly by competitively blocking the binding of Ras protein and its posttranslational modification, as suggested in previous studies. But, the mechanisms by which Arglabin-DMA inhibits tumor growth in vivo and in vitro are still relatively poorly characterized. To determine the mechanism by which this drug inhibits tumor growth, the effects of Arglabin-DMA in two human colon tumor cell lines (mutant K-ras HCT 116 and wild-type ras HT-29) were explored on cell proliferation, apoptosis, and cell cycle kinetics in vitro. In cell viability studies, we showed that Arglabin-DMA …

Mechanisms Of Cell Death Initiated In Herpes Simplex Virus Thymidine Kinase Expressing Colon Tumor Cells Treated With Ganciclovir And Ucn-01, Christina Elizabeth Ahn

Theses and Dissertations in Biomedical Sciences

Metastatic colon carcinoma is the second leading cause of death from malignancy in the United States, and development of more effective treatments is essential. Heterologous expression of Herpes Simplex Virus Thymidine Kinase (HSVtk) in combination with the prodrug, ganciclovir (GCV), has shown great promise for the genetic therapy of many cancers, but most patients have had only a partial or minimal response to the therapy. After screening a panel of two drug combinations, our laboratory has shown that the combination of GCV and the protein kinase inhibitor UCN-01 (7-hydroxystaurosporine) enhances tumor cell death more effectively than either drug alone. However …

Identification And Expansion Of Pancreatic Stem/Progenitor Cells., You-Qing Zhang, Marcie Kritzik, Nora Sarvetnick

Journal Articles: Regenerative Medicine

Pancreatic islet transplantation represents an attractive approach for the treatment of diabetes. However, the limited availability of donor islets has largely hampered this approach. In this respect, the use of alternative sources of islets such as the ex vivo expansion and differentiation of functional endocrine cells for treating diabetes has become the major focus of diabetes research. Adult pancreatic stem cells /progenitor cells have yet to be recognized because limited markers exist for their identification. While the pancreas has the capacity to regenerate under certain circumstances, questions where adult pancreatic stem/progenitor cells are localized, how they are regulated, and even …

Novel Protein-Protein Interactions Regulate The Proteolytic Activity Of The Pro- Apoptotic Serine Protease, Omi/Htra2, Supriya Singh

Electronic Theses and Dissertations

Omi/HtrA2 is a mitochondrial serine protease with high homology to the bacterial HtrA proteins. Omi promotes caspase-dependent apoptosis by binding and degrading IAPs-inhibitor of apoptosis proteins. Omi can also induce caspase-independent apoptosis but the actual mechanism is still unknown. IAP's are not the only substrates cleaved by Omi. There are at least two more known substrates of Omi, the HAX-1 and the ped/pea-15 proteins. HS1-associated protein X-1 (HAX-1) is a mitochondrial protein, degraded by Omi after induction of caspase-dependent apoptosis. Ped/pea-15 is also an anti-apoptotic protein and is cleaved by Omi after induction of caspase-independent apoptosis. The proteolytic activity of …

The Effects Of Arsenic On Selenoprotein Biosythesis, Fanta Konate

Electronic Theses and Dissertations

Arsenic contamination of drinking water is a real public health problem in certain areas of South-East Asia where chronic exposure has been correlated to higher rates of lung, skin, bladder, kidney, and liver cancer. Although arsenic carcinogenicity is well established, the mechanism by which it induces cancer is poorly understood. Recent evidence suggests that oxidative stress could be a possible mechanism for the carcinogenic effects of arsenic. Selenium, in the form of selenocysteine, is necessary for the activity of several enzymes with a role in the defense against reactive oxygen species (ROS), primarily thioredoxin reductases (TrxR) and glutathione peroxidases (Gpx). …

Real Time Rt-Pcr For Direct Detection Of Viable Mycobacterium Avium Subspecies Paratuberculosis In Chron's Disease Patients And Association Of Map Infection With Downregulation In Interferon-Gamma Receptor (Infg1) Gene In Crohn's Disease Patients, Mounir Chehtane

Electronic Theses and Dissertations

Association of Mycobacterium avium subspecies paratuberculosis (MAP) with Crohn's disease (CD) and not with ulcerative colitis (UC), two forms of inflammatory bowel disease (IBD), has been vigorously debated in recent years. This theory has been strengthened by recent culture of MAP from breast milk, intestinal tissue and Blood from patients with active Crohn's disease. Culture of MAP from clinical samples remained challenging due to the fastidious nature of MAP including its lack of cell wall in infected patients. The advent of real time PCR has proven to be significant in infectious disease diagnostics. In this study, real time reverse transcriptase …

Expression Of Hepatitis C Viral Non-Structural 3 Antigen In Transgenic Chloroplasts, Anubhuti Bhati

Electronic Theses and Dissertations

Hepatitis C viral infection is the major cause of acute hepatitis and chronic liver disease and remains the leading cause of liver transplants (NIH). An estimated 180 million people are infected globally (WHO). There is no vaccine available to prevent hepatitis C. The treatment with antiviral drugs is expensive, accompanied with various side effects and is limited only to those at risk of developing advanced liver disease. The treatment is also effective in only about 30% to 50% of treated patients and still a high percentage of patients are resistant to therapy. Therefore, there is an urgent need for the …

Expression Of Cholera Toxin B Subunit-Rotavirus Nsp4 Enterotoxin Fusion Protein In Transgenic Chloroplasts, Anila Kalluri

Electronic Theses and Dissertations

Rotavirus, the major cause of life-threatening infantile gastroenteritis, is a member of the Reoviridae family and is considered to be the single most important cause of virus-based severe diarrheal illness in infants and young children particularly 6 months to 2 years of age in industrialized and developing countries. Infection in infants and young children is often accompanied by severe life threatening diarrhea, most commonly following primary infection. Diarrhea is the major cause of death among children around the world. Responsible for 4 to 6 million deaths per year according to the World Health Organization (WHO), diarrhea is especially dangerous for …

Receptor Mediated Oral Delivery Of Bioencapsulated Green Fluorescent Protein Expressed In Transgenic Chloroplasts, Arati Limaye

Electronic Theses and Dissertations

The skyrocketing costs of prescription medicine in developed countries and their lack of availability in developing countries are the most challenging problems of human health. Primary reasons for such high cost are fermentation-based production, expensive purification methods, the need for low temperature storage and transportation and the delivery through sterile injections. Most of these expenses could be minimized or eliminated when therapeutic proteins are expressed and orally delivered via plant cells. Chloroplasts have the machinery to fold complex and biologically active eukaryotic proteins in the soluble chloroplast stromal compartment. Protein expression through chloroplast transformation system offers a number of advantages …

Protein Sequence Entropy Is Closely Related To Packing Density And Hydrophobicity, H Liao, W Yeh, D Chiang, R L. Jernigan, Brooke Lustig

Faculty Publications, Chemistry

We investigated the correlation between the Shannon information entropy, ‘sequence entropy’, with respect to the local flexibility of native globular proteins as described by inverse packing density. These are determined at each residue position for a total set of 130 query proteins, where sequence entropies are calculated from each set of aligned residues. For the accompanying aggregate set of 130 alignments, a strong linear correlation is observed between the calculated sequence entropy and the corresponding inverse packing density determined at an associated residue position. This region of linearity spans the range of Cα packing densities from 12 to 25 amino …

Selenotrisulfide Derivative Of Alpha-Lipoic Acid: Evaluation In A Cell Culture Model For Potential Use As A Topical Antioxidant, Melenie Lee Alonis

Electronic Theses and Dissertations

Selenium is a required micronutrient in mammalian cells. It is incorporated in the form of selenocysteine into selenoenzymes such as glutathione peroxidase and thioredoxin reductase, and is absolutely required for activity. Thioredoxin reductase is necessary for reduction of oxidized thioredoxin and therefore plays a major role in maintaining the redox status of the cell. Glutathione peroxidase is responsible for reducing peroxides into their corresponding alcohols and water. Together, these selenoenzymes constitute a significant part of the cell's arsenal to defend itself against oxidative stress. Exogenous sources of oxidative stress, such as UV radiation, are capable of generating reactive oxygen species …

Reduced Macrophage Apoptosis Is Associated With Accelerated Atherosclerosis In Low-Denstiy Lipoprotein Receptor-Null Mice, Michael Sinensky, J. Liu, D. P. Thweke, Y. R. Su, M. F. Linton, S. Fazio

Faculty Publications, Biological Sciences

Objective— The majority of apoptotic cells in atherosclerotic lesions are macrophages. However, the pathogenic role of macrophage apoptosis in the development of atherosclerosis remains unclear. Elevated expression of Bax, one of the pivotal proapoptotic proteins of the Bcl-2 family, has been found in human atherosclerotic plaques. Activation of Bax also occurs in free cholesterol-loaded and oxysterol-treated mouse macrophages. In this study, we examined the effect of Bax deficiency in bone marrow-derived leukocytes on the development of atherosclerosis in low-density lipoprotein receptor-null (LDLR−/−) mice. Methods and Results— Fourteen 8-week-old male LDLR−/− mice were lethally irradiated and reconstituted with either wild-type (WT) …

Condensed Protocol For Competent Cell Preparation And Transformation Of The Methylotrophic Yeast Pichia Pastoris, Joan Lin-Cereghino, William Wong, See Xiong, William Giang, Linda Luong, Jane Vu, Sabrina Johnson, Geoff P. Lin-Cereghino

College of the Pacific Faculty Articles

No abstract provided.

Mapping Of Ssdna Nicks Within Dsdna Genomes By Two-Dimensional Gel Electrophoresis, Wayne P. Wahls, K. Mark Dewall, Mari K. Davidson

Journal of the Arkansas Academy of Science

DNA molecules within chromosomes undergo constant, dynamic changes yet maintain the integrity of the primary DNA sequence. DNA replication, adjustment of helical density, resolution of catenenes, repair of DNA damage, and homologous recombination each involve breakage and religation of the phosphate backbone of the double helix. Although the analysis of dsDNA breaks is facile, the analysis of ssDNA nicks is not. The principal impediment is that conventional, one-dimensional electrophoresis methods cannot readily detect ssDNA nicks in the context of dsDNA breaks. We therefore developed a two dimensional (native/denaturing) gel electrophoresis approach to map the positions of ssDNA nicks. Analysis of …

Quality Control During Aminoacyl-Trna Synthesis, M. Praetorius-Ibba, S. Ataide, C. Hausmann, J. Levengood, J. Ling, S. Wang, H. Roy, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The fidelity of translation is determined at two major points: the accuracy of aminoacyl-tRNA selection by the ribosomes and synthesis of cognate amino acid/tRNA pairs by aminoacyl-tRNA synthetases (aaRSs) in the course of the aminoacylation reaction. The most important point in aminoacylation is the accurate recognition of cognate substrates coupled with discrimination of non-cognates. While this is generally accomplished by a single enzyme, we have recently found that discrimination against lysine analogues requires the existence of two unrelated lysyl-tRNA synthetases. For other amino acids, initial recognition is not sufficiently accurate with errors being corrected by an intrinsic editing activity. Recent …

A Novel Binding Interaction For The Paxillin Ld3 Motif: Paxillin Ld3 Mediates Merlin-Paxillin Binding At Paxillin Binding Domain 1, Sandra E. Beattie Geden

Electronic Theses and Dissertations

Neurofibromatosis type 2, an autosomal dominant genetic disorder, causes predisposed individuals to develop various benign central and peripheral nervous system tumors. The characteristic tumors of this disease are schwannomas, which are tumors of the Schwann cells, typically on the vestibular nerve. These and the other associated tumors slowly compress nervous system structures causing deafness and loss of balance, resulting in an average life-span of less than 40 years. The product of the Nf2 gene is the protein named merlin or schwannomin. In individuals diagnosed with NF2, merlin is either absent or mutated to the point of inactivation. As such, merlin …

Characterization Of Photosynthetic Reaction Centers From Bradyrhizobium Strain Btai 1, Isaac P. Forquer

Browse all Theses and Dissertations

Photosynthetic rhizobia have been studied for about 15 years now. They are now considered to be metabolically aligned with a relatively recently discovered group of bacteria, the anoxygenic aerobic phototrophs (AAP’s).Rhizobia form symbiotic relationships with plants from the Fabaceae family. Photosynthetic rhizobia not only nodulate the roots, as most other rhizobia do, but they also form nodules on the stems of certain leguminous plants. The plant provides carbon to the bacteria and the bacteria provides the plant with soluble nitrogen fixed from the biologically inert but abundant atmospheric N2. A key question regarding photosynthetic rhizobia and other AAP’s derives from …

Identification Of Fatty Acid Oxidation Disorder Patients With Lowered Acyl-Coa Thioesterase Activity In Human Skin Fibroblasts, Mary Hunt, Jos Ruiter, Petra Mooyer, Carlo W T Van Roermond, Rob Ofman, Lodewig Ijlst, Ronald J A Wanders

Articles

Background: Acyl-CoA thioesterases are enzymes that hydrolyze acyl-CoAs to the free fatty acid and coenzyme A (CoASH). These enzymes have been identified in several cellular compartments and are thought to regulate intracellular levels of acyl-CoAs, free fatty acids and CoASH. However, to date no patients deficient in acyl-CoA thioesterases have been identified. Design: Acyl-CoA thioesterase activity was measured in human skin fibroblasts. Western blot analysis was used to determine Type-II acyl-CoA thioesterase protein levels in patients. Results: Activity was found in human fibroblasts with all saturated acyl-CoAs from C4:0- to C18:0-CoA, with highest activity detected with lauroyl-CoA and myristoyl-CoA (C12:0 …

New Insights Into Bile Acid Amidation, Mary Hunt, Eithne O'Shea, Karianne Solaas, Bengt Kase, Stefan Alexson

Articles

No abstract provided.

Regulation Of Sparc Gene Expression By The Activator Protein 1 Transcription Factor, Joseph William Briggs

Theses and Dissertations in Biomedical Sciences

Overexpression of the c-Jun proto-oncogene in MCF7 breast cancer cells results in a variety of phenotypic changes related to malignant progression including a shift to estrogen independent growth, increased cell motility and invasion. Concurrent with these phenotypic changes are alterations to cellular gene expression patterns. One gene that becomes highly upregulated is SPARC (secreted protein acidic and rich in cysteine). Increased SPARC expression is associated with malignant progression in a variety of different cancers, although little is known regarding the mechanisms of SPARC gene regulation. Therefore, the objectives of this study were: (1) to determine the mechanisms by which c-Jun …

Tumor Response Tcf-4/Β-Catenin Regulatory Elements For Enhancing Cancer Gene Therapies, Saurabh Kumar Gupta

Theses and Dissertations in Biomedical Sciences

Mutations in the adenomatous polyposis coli gene are frequently associated with progression of colon carcinoma and most other types of epithelial carcinomas. This usually results in stabilization of β-catenin protein levels, followed by transactivation of Tcf-4/β-catenin responsive genes. The effectiveness of a Tcf-4/β-catenin transcriptional enhancer element in combination with a c-fos or carcinoembryonic antigen promoter was tested for its ability to act as a tumor specific regulator of gene expression in a panel of human tumor and normal cell lines. Luciferase reporter assays indicated enhanced activity of the Tcf-4/β-catenin transcriptional element only in tumor cell lines, with minimal activities in …

Isolation Of Cancer Stem Cells From Adult Glioblastoma Multiforme, Xianpeng Yuan, James Curtin, Yizhi Xiong, Gentao Liu, Sebastian Waschsmann-Hogiu, Daniel Farkas, Keith Black, John Yu

Articles

Glioblastoma multiforme (GBM) is the most common adult primary brain tumor and is comprised of a heterogeneous population of cells. It is unclear which cells within the tumor mass are responsible for tumor initiation and maintenance. In this study, we report that brain tumor stem cells can be identified from adult GBMs. These tumor stem cells form neurospheres, possess the capacity for self-renewal, express genes associated with neural stem cells (NSCs), generate daughter cells of different phenotypes from one mother cell, and differentiate into the phenotypically diverse populations of cells similar to those present in the initial GBM. Having a …

Rhodobacter Capsulatus Porphobilinogen Synthase, A High Activity Metal Ion Independent Hexamer, David Bollivar

Scholarship

No abstract provided.

Phylogenetic Analysis Of The Formin Homology 2 Domain, Henry N. Higgs, Kevin J. Peterson

Dartmouth Scholarship

Formin proteins are key regulators of eukaryotic actin filament assembly and elongation, and many species possess multiple formin isoforms. A nomenclature system based on fundamental features would be desirable, to aid the rapid identification and characterization of novel formins. In this article, we attempt to systematize the formin family by performing phylogenetic analyses of the formin homology 2 (FH2) domain, an independently folding region common to all formins, which alone can influence actin dynamics. Through database searches, we identify 101 FH2 domains from 26 eukaryotic species, including 15 in mice. Sequence alignments reveal a highly conserved yeast-specific insert in the …

On Thacker's Biomedia (2004), Nicholas Ruiz Iii

Reconstruction: Studies in Contemporary Culture

[First paragraph]

Only we could have done it. The Code (DNA and its analogs, etc.) that we perhaps only narrate, never forgetting all of the fictions that narration portends, today consciously edits the text that evolution has edited unconsciously for eons. Thacker considers how humans -- perhaps little more than interactive Code, manipulate the Code -- with the technology of the Code. No other faction of Code has yet to make such heady ‘gains.’ Where posthumanity was always a literary endeavor, a literary bypass, out of instrumental science and into fictive states, it now is a technical endeavor, encompassing a …

Paradigm Shifts And New Worldviews: Kuhn, Laudan And Discovery In Molecular Biology, Priya Venkatesan

Reconstruction: Studies in Contemporary Culture

[Editors' Introduction]

The author poses an alternate set of ideas concerning paradigms, normal science, research traditions and scientific revolution on the basis of the unique and inherently distinctive development of molecular biology and genetics; for, a new set of conceptual tools concerning scientific progress are required for an adequate understanding of how biological processes were elucidated under the scientific auspices of the central dogma of the genetic code. This essay concentrates on a limited study of three aspects in genetics: the study of chromosome structure, dynamics and function, reverse transcriptases, and the discovery of RNA catalysts. In attempting to analyze …

Cloning And Functional Analysis Of The Putative Tetracycline Resistance Gene Hp1165 In Helicobacter Pylori, Yuhuan Li

All-Inclusive List of Electronic Theses and Dissertations

Tetracycline has been used in combination with other antibiotics in treatment of Helicobacter pylori infection. However, tetracycline resistance has developed in clinical isolates of H. pylori, rendering treatment failure. Mutations in the 16S rRNA gene have been reported to mediate tetracycline resistance in some patient isolates. Nevertheless, the diversity of tetracycline resistance cases suggests multiple genes are involved. HPl 165, a putative tetracycline resistance gene in the genome of H. pylori 26695, displays 49.8% identity to the tetracycline efflux gene tetA (P) from Clostridium perfringens. To determine the function of the HPl 165 gene and gain a better understanding of …