Medical Sciences Commons^™

An Intramolecular Association Between Two Domains Of The Protein Kinase Fused Is Necessary For Hedgehog Signaling, Manuel Ascano Jr., David J. Robbins

Dartmouth Scholarship

The protein kinase Fused (Fu) is an integral member of the Hedgehog (Hh) signaling pathway. Although genetic studies demonstrate that Fu is required for the regulation of the Hh pathway, the mechanistic role that it plays remains largely unknown. Given our difficulty in developing an in vitro kinase assay for Fu, we reasoned that the catalytic activity of Fu might be highly regulated. Several mechanisms are known to regulate protein kinases, including self-association in either an intra- or an intermolecular fashion. Here, we provide evidence that Hh regulates Fu through intramolecular association between its kinase domain (ΔFu) and its carboxyl-terminal …

P14arf : A P53-Independent Tumor Suppressor, Monte W. Miller

Loma Linda University Electronic Theses, Dissertations & Projects

Many genetic alterations at the CDKN2A locus on human chromosome 9 have been shown to be at least partially responsible for transformation of cells to a cancerous phenotype. This locus encodes two proteins, p16 and p14, that play a pivotal role in tumor surveillance.

Breakdowns in the p14 pathway have been estimated to be present in approximately 40% of human cancers and only recently have its binding partners and effects begun to be defined. Its interaction with the p53 pathway, which is estimated to be inactivated or mutated in 50% of all cancers, makes it difficult to determine its own …

Characterization Of The Chicken Inward Rectifier K+ Channel Irk1/Kir2.1 Gene., Hideki Mutai, Lawrence C Kenyon, Emily Locke, Nami Kikuchi, John Carl Oberholtzer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Inward rectifier potassium channels (IRK) contribute to the normal function of skeletal and cardiac muscle cells. The chick inward rectifier K+ channel cIRK1/Kir2.1 is expressed in skeletal muscle, heart, brain, but not in liver; a distribution similar but not identical to that of mouse Kir2.1. We set out to explore regulatory domains of the cIRK1 promoter that enhance or inhibit expression of the gene in different cell types. RESULTS: We cloned and characterized the 5'-flanking region of cIRK1. cIRK1 contains two exons with splice sites in the 5'-untranslated region, a structure similar to mouse and human orthologs. cIRK1 has …

Heme Oxygenase-2 Gene Deletion Attenuates Oxidative Stress In Neurons Exposed To Extracellular Hemin., Raymond F Regan, Jing Chen, Luna Benvenisti-Zarom

Department of Emergency Medicine Faculty Papers

BACKGROUND: Hemin, the oxidized form of heme, accumulates in intracranial hematomas and is a potent oxidant. Growing evidence suggests that it contributes to delayed injury to surrounding tissue, and that this process is affected by the heme oxygenase enzymes. In a prior study, heme oxygenase-2 gene deletion increased the vulnerability of cultured cortical astrocytes to hemin. The present study tested the effect of HO-2 gene deletion on protein oxidation, reactive oxygen species formation, and cell viability after mixed cortical neuron/astrocyte cultures were incubated with neurotoxic concentrations of hemin. RESULTS: Continuous exposure of wild-type cultures to 1-10 microM hemin for 14 …

Durable Cytotoxic Immune Responses Against Gp120 Elicited By Recombinant Sv40 Vectors Encoding Hiv-1 Gp120 +/- Il-15., Hayley J Mckee, Patricia Y T'Sao, Maria Vera, Puri Fortes, David S Strayer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: A vaccine that elicits durable, powerful anti-HIV immunity remains an elusive goal. In these studies we tested whether multiple treatments with viral vector-delivered HIV envelope antigen (gp120), with and without IL-15, could help to approach that goal. For this purpose, we used recombinant Tag-deleted SV40-derived vectors (rSV40s), since they do not elicit neutralizing antibody responses, and so can be given multiply without loss of transduction efficiency. METHODS: SV(gp120) carried the coding sequences for HIV-1NL4-3 Env, and SV(mIL-15) carried the cDNA for mouse IL-15. Singly, and in combination, these two vectors were given monthly to BALB/cJ mice. Cytotoxic immunity and …

Sadb Is Required For The Transition From Reversible To Irreversible Attachment During Biofilm Formation By Pseudomonas Aeruginosa Pa14, Nicky C. Caiazza, George A. O'Toole

Dartmouth Scholarship

Current models of biofilm formation by Pseudomonas aeruginosa propose that (i) planktonic cells become surface associated in a monolayer, (ii) surface-associated cells form microcolonies by clonal growth and/or aggregation, (iii) microcolonies transition to a mature biofilm comprised of exopolysaccharide-encased macrocolonies, and (iv) cells exit the mature biofilm and reenter the planktonic state. Here we report a new class of P. aeruginosa biofilm mutant that defines the transition from reversible to irreversible attachment and is thus required for monolayer formation. The transposon insertion carried by the sadB199 mutant was mapped to open reading frame PA5346 of P. aeruginosa PA14 and encodes …

Food Based Approaches For A Healthy Nutrition In Africa, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The latest estimates of the FAO demonstrate the problems of the fight against hunger. These problems are manifested by the ever-increasing number of chronically undernourished people worldwide. Their numbers during the 1999-2001 period were estimated at about 840 million of which 798 million live in developing countries. Sub-Saharan Africa alone represented 198 million of those. In this part of Africa the prevalence of undernourishment ranges from 5-34%, causing growth retardation and insufficient weight gain among one third of the children under five years of age and resulting in a mortality of 5-15% among these children. Malnutrition resulting from undernourishment is …

Update - March 2004, Loma Linda University Center For Christian Bioethics

Update

In this issue:

-- Christians Contemplating New Developments in Biomedicine
-- Editorial
-- Christian Principals of Genetic Intervention
-- Statement on Ethical Considerations Regarding Human Cloning
-- Honoring the Religious Impulse Within the Arena of Genetic Counseling

The Nad(P)H Oxidase Homolog Nox4 Modulates Insulin-Stimulated Generation Of H202 And Plays An Integral Role In Insulin Signal Transduction, Kalyankar Mahadev, Hiroyuki Motoshima, Xiangdong Wu, Jean Marie Ruddy, Rebecca S. Arnold, Guangjie Cheng, J. David Lambeth, Barry J. Goldstein

Department of Medicine Faculty Papers

Insulin stimulation of target cells elicits a burst of H₂O₂ that enhances tyrosine phosphorylation of the insulin receptor and its cellular substrate proteins as well as distal signaling events in the insulin action cascade. The molecular mechanism coupling the insulin receptor with the cellular oxidant-generating apparatus has not been elucidated. Using reverse transcription-PCR and Northern blot analyses, we found that Nox4, a homolog of gp91phox, the phagocytic NAD(P)H oxidase catalytic subunit, is prominently expressed in insulin-sensitive adipose cells. Adenovirus-mediated expression of Nox4 deletion constructs lacking NAD(P)H or FAD/NAD(P)H cofactor binding domains acted in a dominant-negative …

A Drosophila Protein-Interaction Map Centered On Cell-Cycle Regulators, Clement A. Stanyon, Guozhen Liu, Bernardo A. Mangiola, Nishi Patel, Loic Giot, Bing Kuang, Huamei Zhang, Jinhui Zhong, Russell L. Finley Jr

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Maps depicting binary interactions between proteins can be powerful starting points for understanding biological systems. A proven technology for generating such maps is high-throughput yeast two-hybrid screening. In the most extensive screen to date, a Gal4-based two-hybrid system was used recently to detect over 20,000 interactions among Drosophila proteins. Although these data are a valuable resource for insights into protein networks, they cover only a fraction of the expected number of interactions.

Results

To complement the Gal4-based interaction data, we used the same set of Drosophila open reading frames to construct arrays for a LexA-based two-hybrid system. We …

Incremental Genetic K-Means Algorithm And Its Application In Gene Expression Data Analysis, Yi Lu, Shiyong Lu, Farshad Fotouhi, Youping Deng, Susan J. Brown

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

In recent years, clustering algorithms have been effectively applied in molecular biology for gene expression data analysis. With the help of clustering algorithms such as K-means, hierarchical clustering, SOM, etc, genes are partitioned into groups based on the similarity between their expression profiles. In this way, functionally related genes are identified. As the amount of laboratory data in molecular biology grows exponentially each year due to advanced technologies such as Microarray, new efficient and effective methods for clustering must be developed to process this growing amount of biological data.

Results

In this paper, we propose a new clustering …

Imaging Genome Abnormalities In Cancer Research, Henry Hq Heng, Joshua B. Stevens, Guo Liu, Steven W. Bremer, Christine J. Ye

Wayne State University Associated BioMed Central Scholarship

Abstract

Increasing attention is focusing on chromosomal and genome structure in cancer research due to the fact that genomic instability plays a principal role in cancer initiation, progression and response to chemotherapeutic agents. The integrity of the genome (including structural, behavioral and functional aspects) of normal and cancer cells can be monitored with direct visualization by using a variety of cutting edge molecular cytogenetic technologies that are now available in the field of cancer research. Examples are presented in this review by grouping these methodologies into four categories visualizing different yet closely related major levels of genome structures. An integrated …

The Pattern And Frequency Of T(14;18) Translocation And Immunophenotype In Asian Follicular Lymphoma, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

Aims: Follicular lymphoma is frequently associated with t(14;18)(q32;q21) translocation. This study was undertaken to determine the pattern of Bcl-2, CD10 and Bcl-6 expression in relation to t(14;18) translocation in follicular lymphoma from a cohort of a multi-ethnic Asian population. Methods and results: Sixty-two cases of follicular lymphoma were retrieved for immunohistochemistry, and t(14;18) translocation analysis by polymerase chain reaction and fluorescent in-situ hybridization techniques. Bcl-2 expression was present in 74% of the cases. CD10 expression was also relatively low (61%), with decreasing frequency of expression in high-grade tumours. Bcl-6 protein was expressed in most of the tumours (88%) regardless of …

Apolipoprotein E Genotyping In The Malay, Chinese And Indian Ethnic Groups In Malaysia - A Study On The Distribution Of The Different Apoe Alleles And Genotypes, Mary Anne Tan Jin Ai

Mary Anne Tan Jin Ai

Background: Apolipoprotein E (apoE) is encoded by a polymorphic gene located on chromosome 19. The three common apoE alleles are epsilon2, epsilon3 and epsilon4. We studied the frequencies of the apoE alleles and genotypes in the three ethnic groups-Malay, Chinese and Indian-in Malaysia using DNA amplification followed by agarose gel electrophoresis. Methods: EDTA blood was collected and DNA was extracted using proteinase K-SDS digestion and purified by phenol-chloroform extraction. The apoE gene sequence was amplified using the PCR and apoE genotyping was performed by restriction enzyme digestion with HhaI. Results: Genotyping of the apoE gene produces six genotypes-E2/E2, E2/E3, E3/E3, …

The Genetic And Molecular Characterization Of The Polycystic Kidney Disease-Causing Mouse Gene Bicc1, Sarah J. Price

Theses, Dissertations and Capstones

Polycystic kidney disease (PKD) is one of the most common hereditary diseases and is characterized by progressive cyst formation, substantial renal enlargement, and frequently, progression to end-stage renal disease. One way to learn more about the etiology of this disease is to study mouse models that imitate the human situation. The juvenile congenital polycystic kidney disease (jcpk) gene on mouse Chromosome 10 has been found to cause a severe, early onset form of PKD when inherited in an autosomal recessive manner (Flaherty et al., 1995). Previous genetic studies mapped the jcpk locus to a 1 cM region on mouse Chromosome …

The Nuclear Pore Complex And The Dead Box Protein Rat8p/Dbp5p Have Nonessential Features Which Appear To Facilitate Mrna Export Following Heat Shock, Christiane Rollenhagen, Christine A. Hodge, Charles N. Cole

Dartmouth Scholarship

Nuclear pore complexes (NPCs) play an essential role in RNA export. Nucleoporins required for mRNA export in Saccharomyces cerevisiae are found in the Nup84p and Nup82p subcomplexes of the NPC. The Nup82p subcomplex contains Nup82p, Rat7p/Nup159p, Nsp1p, Gle1p/Rss1p, and Rip1p/Nup42p and is found only on the cytoplasmic face of NPCs. Both Rat7p and Gle1p contain binding sites for Rat8p/Dbp5p, an essential DEAD box protein and putative RNA helicase. Rip1p interacts directly with Gle1p and is the only protein known to be essential for mRNA export after heat shock but not under normal growth conditions. We report that in cells lacking …

Creation Of Non-Human Primate Neurogenetic Disease Models By Gene Targeting And Nuclear Transfer, Robert B. Norgren

Journal Articles: Genetics, Cell Biology & Anatomy

Genetically modified rhesus macaques are necessary because mouse models are not suitable for a number of important neurogenetic disorders; for example, Kallmann's syndrome, Lesch-Nyhan's disease and Ataxia-Telangiectasia. Mouse models may not be suitable because there may be no mouse ortholog of the human gene of interest, as is the case for Kallmann's syndrome, or because mutant mice do not exhibit the same phenotype observed in humans, as is the the case for Lesch-Nyhan's disease and Ataxia-Telangiectasia. Non-human primate models of neurogenetic diseases are expected to more closely resemble human diseases than existing mouse models. Genetically modified rhesus macaques can be …