Medicine and Health Sciences Commons^™

Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta

Journal Articles: Biochemistry & Molecular Biology

The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …

Biomolecular Tuning Of Electronic Transport Properties Of Carbon Nanotubes Via Antibody Functionalization, Kasif Teker, Dr. Eric Wickstrom, Balaji Panchapakesan

Department of Biochemistry and Molecular Biology Faculty Papers

Carbon nanotubes (CNTs) are remarkable solidstate nanomaterials due to their unique electrical and mechanical properties. The electronic properties of nanotubes combined with biological molecules such as proteins could make miniature devices for biological sensing applications. In this paper, the noncovalent interaction of single-wall CNTs with antibodies is presented for its potential applications for detecting overexpressed cell surface receptors in breast cancer cells. The degree of binding of antibodies on CNTs was found to be more than 80% for an extended sampling area by confocal microscopy. The key to achieve such high degree of functionalization is due to the separation of …

Multiple Domains In Siz Sumo Ligases Contribute To Substrate Selectivity., Alison Reindle, Irina Belichenko, Gwendolyn R Bylebyl, Xiaole L Chen, Nishant Gandhi, Erica S Johnson

Department of Biochemistry and Molecular Biology Faculty Papers

Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of …

Bibliography Of Secondary Sources On The History Of Dermatology Iii. Books, Monographs, And Chapters In English Supplemented Through 2005., Lawrence Charles Parish, John Thorne Crissey, Jennifer L Parish, Daniel H Parish

Department of Dermatology and Cutaneous Biology Faculty Papers

Providing supplements to the history of dermatology bibliographic record has been a continuous project for the past four decades. When the endeavor was initiated, the original authors decided that only contributions in English and those directly related to dermatology, excluding sexually transmitted diseases as such, would be indexed.

There is the perennial question of whether such a manually created bibiliographic project has a need. The obvious answer remains yes. While Index Medicus has expanded the number of journals that are indexed, the number of dermatology publications currently included by Index Medicus is just over fifty. Granted, most of the papers …

Diabetes Alters Vascular Mechanotransduction: Pressure-Induced Regulation Of Mitogen Activated Protein Kinases In The Rat Inferior Vena Cava, Kevin M. Rice, Devashish H. Desai, Sunil K. Kakarla, Anjaiah Katta, Deborah L. Preston, Paulette Wehner, Eric R. Blough

MIIR Faculty Research

Background

Diabetes mellitus is an important risk factor for increased vein graft failure after bypass surgery. However, the cellular and molecular mechanism(s) underlying vessel attrition in this population remain largely unexplored. Recent reports have suggested that the pathological remodeling of vein grafts may be mediated by mechanically-induced activation of the mitogen activated protein kinase (MAPK) signaling pathways and the MAPK-related induction of caspase-3 activity. On the basis of these findings, we hypothesized that diabetes may be associated with alterations in how veins "sense" and "respond" to altered mechanical loading.

Methods

Inferior venae cavae (IVC) from the non-diabetic lean (LNZ) and …

Silica-Coated Lanthanum-Strontium Manganites For Hyperthermia Treatments, Vuk Uskoković, Aljoša Košak, Miha Drofenik

Pharmacy Faculty Articles and Research

La_0.76Sr_0.24MnO_{3 + δ} particles, prepared by performing a traditional, solid-state method of synthesis, were coated by uniform layers of silica via initiating hydrolysis and condensation of TEOS in aqueous–alcoholic alkali environment. The eventually obtained samples exhibited Curie temperature at ∼40 °C, and comprised core-shell particles of ∼250 nm in diameter. By varying stoichiometric ratio of cations within manganite cores of the particles, Curie point of the resulting material can be varied too, thus opening a way for the simple design of biocompatible, temperature-self-regulating particles for application in hyperthermia treatments, with Curie point thereof adjusted to …

High-Affinity Binding Of The Nc1 Domain Of Collagen Vii To Laminin 5 And Collagen Iv, Raymond Brittingham, Jouni Uitto, Andrzej Fertala

Department of Dermatology and Cutaneous Biology Faculty Papers

Anchoring functions of collagen VII depend on its ability to form homotypic fibrils and to bind to other macromolecules to form heterotypic complexes. Biosensor-based binding assays were employed to analyze the kinetics of the NC1 domain-mediated binding of collagen VII to laminin 5, collagen IV, and collagen I. We showed that collagen VII interacts with laminin 5 and collagen IV with Kd values of 10-9 M. In contrast, the NC1-mediated binding to collagen I was weak with a Kd value of 10-6 M. Binding assays also showed that the NC1 domain utilizes the same region to bind to both laminin …

Circadian Rhythmicity By Autocatalysis, Arun Mehra, Christian I. Hong, Mi Shi, Jennifer J. Loros, Jay C. Dunlap, Peter Ruoff

Dartmouth Scholarship

The temperature compensated in vitro oscillation of cyanobacterial KaiC phosphorylation, the first example of a thermodynamically closed system showing circadian rhythmicity, only involves the three Kai proteins (KaiA, KaiB, and KaiC) and ATP. In this paper, we describe a model in which the KaiA- and KaiB-assisted autocatalytic phosphorylation and dephosphorylation of KaiC are the source for circadian rhythmicity. This model, based upon autocatalysis instead of transcription-translation negative feedback, shows temperature-compensated circadian limit-cycle oscillations with KaiC phosphorylation profiles and has period lengths and rate constant values that are consistent with experimental observations.

The Vaccinia-Related Kinases Phosphorylate The N' Terminus Of Baf, Regulating Its Interaction With Dna And Its Retention In The Nucleus, R. Jeremy Nichols, Matthew S. Wiebe, Paula Traktman

Nebraska Center for Virology: Faculty Publications

The vaccinia-related kinases (VRKs) comprise a branch of the casein kinase family whose members are characterized by homology to the vaccinia virus B1 kinase. The VRK orthologues encoded by Caenorhabditis elegans and Drosophila melanogaster play an essential role in cell division; however, substrates that mediate this role have yet to be elucidated. VRK1 can complement the temperature sensitivity of a vaccinia B1 mutant, implying that VRK1 and B1 have overlapping substrate specificity. Herein, we demonstrate that B1, VRK1, and VRK2 efficiently phosphorylate the extreme N' terminus of the BAF protein (Barrier to Autointegration Factor). BAF binds to both DNA and …

Secondary N-Nitrosocarbamate Anions: Structure And Alkylation Reactions. A Dft Study, Vladimir Benin

Chemistry Faculty Publications

The current article reports theoretical studies (DFT: B3LYP/6-31+G(d)) on the structure and alkylation reactions of the anions of some secondary N-nitrosocarbamates, a class of ambident nucleophiles whose chemistry has been little explored. Several anions (1–4), with an increasing size of the carbamate alkyl (aryl) group were investigated, in an attempt to establish the influence of the size of that group on the thermal stability and regioselectivity of alkylation of the title anions. The conclusion is that thermal stability and the mode of reaction are affected significantly only in the presence of very large and branched carbamate groups. The thermal …

The Ribosome-Recycling Step: Consensus Or Controversy?, Go Hirokawa, Natalia Demeshkina, Nobuhiro Iwakura, Hideko Kaji, Akira Kaji

Department of Biochemistry and Molecular Biology Faculty Papers

Ribosome recycling, the last step in translation, is now accepted as an essential process for prokaryotes. In 2005, three laboratories showed that ribosome-recycling factor (RRF) and elongation factor G (EF-G) cause dissociation of ribosomes into subunits, solving the long-standing problem of how this essential step of translation occurs. However, there remains ongoing controversy regarding the other actions of RRF and EF-G during ribosome recycling. We propose that the available data are consistent with the notion that RRF and EF-G not only split ribosomes into subunits but also participate directly in the release of deacylated tRNA and mRNA for the next …

Lung Development In Laminin Γ2 Deficiency: Abnormal Tracheal Hemidesmosomes With Normal Branching Morphogenesis And Epithelial Differentiation, Nguyet M. Nguyen, Leena Pulkkinen, Jessica A. Schlueter, Guerrino Meneguzzi, Jouni Uitto, Robert M. Senior

Department of Dermatology and Cutaneous Biology Faculty Papers

Background

Laminin γ2 (Lamc2), one of the polypeptides in laminin-332 (laminin-5), is prominent in the basement membrane of alveolar walls and airways of developing and adult lung. Laminins are important for lung morphogenesis and based on its localization, a function for laminin γ2 in lung development has been hypothesized. Targeted deletion of the laminin γ2 gene in mice results in skin blistering and neonatal death at 3–5 days after birth due to failure to thrive.

Methods

Examination of lung development in Lamc2-/- mice through 1–2 days postnatal was accomplished by morphometric analysis, lung bud culture, electron microscopy, immunohistochemical …

Antisense Inhibition Of Cyclin D1 Expression Is Equivalent To Flavopiridol For Radiosensitization Of Zebrafish Embryos, Mary Frances Mcaleer, Kevin T. Duffy, William R. Davidson, Gabor Kari, Adam P. Dicker, Ulrich Rodeck, Eric Wickstrom

Department of Biochemistry and Molecular Biology Faculty Papers

Purpose: Flavopiridol, a small molecule pan-cyclin inhibitor, has been shown to enhance the radiation response of tumor cells both in vitro and in vivo. The clinical utility of flavopiridol, however, is limited by toxicity, previously attributed to pleiotropic inhibitory effects on several targets affecting multiple signal transduction pathways. Here we utilized zebrafish embryos to investigate radiosensitizing effects of flavopiridol in normal tissues.

Methods and Materials: Zebrafish embryos at the 1-4 cell stage were treated with 500 nM flavopiridol or injected with 0.5 pmol antisense hydroxylprolyl-phosphono nucleic acid oligomers to reduce cyclin D1 expression, then subjected to ionizing radiation (IR) or …

Preparation Of Some Substituted Terephthalic Acids, Susanna Branion, Vladimir Benin

Chemistry Faculty Publications

We report in detail the preparation of two substituted terephthalic acids: 2‐sulfomethylterephthalic acid (1) and 2‐phosphonoterephthalic acid (2). Efficient, short syntheses have been developed for both compounds. They are potentially useful monomers for construction of acid‐pendant polymer chains.

Preparation, Characterization And Dft Studies Of Some New N-Nitrosocarbamates And N-Nitrosoureas, Ragavan Narayanan, Helene Hedian, Eric Shamo, Vladimir Benin

Chemistry Faculty Publications

We are presenting the preparation, characterization and density functional theory (DFT) studies {B3LYP/6-31+G(d)) of several reiated classes of N-nitrosocarbamates and N-nitrosoureas. The iong-range goal is the design and preparation of compounds, which would undergo photochemical or hydrolytic decomposition, to yield stabilized cyclic cations that can serve as alkylating agents at various nucleophilic centers, including DNA bases.

Rapid Determination Of Reduced And Oxidized Glutathione Levels Using A New Thiol-Masking Reagent And The Enzymatic Recycling Method: Application To The Rat Liver And Bile Samples, Imam H. Shaik, Reza Mehvar

Pharmacy Faculty Articles and Research

A microtiter plate assay for quantitation of reduced (GSH) and oxidized (GSSG) glutathione in the rat liver tissue and bile is described. The assay is based on the established enzymatic recycling method and a new thiol-masking reagent, 1-methyl-4-vinyl-pyridinium trifluoromethane sulfonate (M4VP). Samples were first processed by homogenization with (liver) or addition of (bile) sulfosalicylic acid. The total glutathione and GSSG were then determined before and after rapid (>= 2 min) and efficient (100%) masking of the GSH content of the samples with M4VP followed by the enzymatic recycling assay. The percentages of error and coefficient of variation of the …

Or.76. Myelin Specific Regulatory T-Cells Expand From Naturally Occurring Regulatory T-Cells And Accumulate In The Cns During Eae [Abstract Only], Thomas Korn, Jay Reddy, Wenda Gao, Terry Strom, Mohamed Oukka, Vijay K. Kuchroo

Jay Reddy Publications

FoxP3 is a lineage specific marker for regulatory T-cells (Treg). We have generated FoxP3 knock-in (KI) mice by introducing a bicistronic GFP reporter into the endogenous FoxP3 locus, allowing us to faithfully track T-reg in vivo. Recently, we have also generated a MOG 35-55/IAb-tetramer. The combination of these two technologies enables us to study the in vivo behavior of myelin specific T-reg and effector T-cells (T-eff) during EAE. Upon immunization with MOG 35-55, we identified a population of MOG-tetramerreactive T-reg in the peripheral lymphoid compartment. T-reg trafficked to the CNS where they were readily detected as early as day 10 …

Or.107. Tim-1 Plays A Crucial Role In The Expansion Of Autopathogneic T-Cells And Regulation Of Autoimmunity [Abstract Only], Sheng Xioa, Nader Najafian, Jay Reddy, Monica Albin, Chen Zhu, Ana Anderson, Zheng Zhang, Cristina Gutierrez, Raymond Sobel, Dale Umetsu, Hideo Yagita, Hisaya Akiba, Mohamed Sayegh, Rosemarie Dekruyff, Vijay K. Kuchroo

Jay Reddy Publications

T-cell immunoglobulin and mucin (TIM) family Members are differentially expressed on Th1 and Th2 cells. Polymorphisms of TIM-1 have been associated with susceptibility to asthma; however, its role in regulating autoimmunity has not been studied. Here, we have used an agonistic antiTIM-1 antibody (Ab, Clone 3B3) which has previously been shown to costimulate T-cell activation and expansion, to analyze the role of TIM-1 in the development and regulation of experimental autoimmune encephalomyelitis (EAE). Treatment with 3B3 dramatically enhances the severity of EAE as well as the frequency of encephalitogenic CD4+ T-cells and the production of IFN-g and IL-17 by these …

Linking Ligand-Induced Alterations In Androgen Receptor Structure To Differential Gene Expression: A First Step In The Rational Design Of Selective Androgen Receptor Modulators, Dmitri Kazmin, Tatiana Prytkova, C. Edgar Cook, Russell Wolfinger, Tzu-Ming Chu, David Beratan, J. D. Norris, Ching-Yi Chang, Donald P. Mcdonnell

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We have previously identified a family of novel androgen receptor (AR) ligands that, upon binding, enable AR to adopt structures distinct from that observed in the presence of canonical agonists. In this report, we describe the use of these compounds to establish a relationship between AR structure and biological activity with a view to defining a rational approach with which to identify useful selective AR modulators. To this end, we used combinatorial peptide phage display coupled with molecular dynamic structure analysis to identify the surfaces on AR that are exposed specifically in the presence of selected AR ligands. Subsequently, we …

Characterization Of Hard2, A Processed Hard1 Gene Duplicate, Encoding A Human Protein N-Alpha-Acetyltransferase., Thomas Arnesen, Matthew J Betts, Frédéric Pendino, David A Liberles, Dave Anderson, Jaime Caro, Xianguo Kong, Jan E Varhaug, Johan R Lillehaug

Department of Medicine Faculty Papers

BACKGROUND: Protein acetylation is increasingly recognized as an important mechanism regulating a variety of cellular functions. Several human protein acetyltransferases have been characterized, most of them catalyzing epsilon-acetylation of histones and transcription factors. We recently described the human protein acetyltransferase hARD1 (human Arrest Defective 1). hARD1 interacts with NATH (N-Acetyl Transferase Human) forming a complex expressing protein N-terminal alpha-acetylation activity. RESULTS: We here describe a human protein, hARD2, with 81 % sequence identity to hARD1. The gene encoding hARD2 most likely originates from a eutherian mammal specific retrotransposition event. hARD2 mRNA and protein are expressed in several human cell lines. …