Life Sciences Commons^™

The Lin-4 Regulatory Rna Controls Developmental Timing In Caenorhabditis Elegans By Blocking Lin-14 Protein Synthesis After The Initiation Of Translation, Philip Olsen, Victor Ambros

Victor R. Ambros

lin-4 encodes a small RNA that is complementary to sequences in the 3' untranslated region (UTR) of lin-14 mRNA and that acts to developmentally repress the accumulation of LIN-14 protein. This repression is essential for the proper timing of numerous events of Caenorhabditis elegans larval development. We have investigated the mechanism of lin-4 RNA action by examining the fate of lin-14 mRNA in vivo during the time that lin-4 RNA is expressed. Our results indicate that the rate of synthesis of lin-14 mRNA, its state of polyadenylation, its abundance in the cytoplasmic fraction, and its polysomal sedimentation profile do not …

A Comparative Gene Map Of The Horse (Equus Caballus), Alexandre R. Caetano, Yow-Ling Shiue, Leslie A. Lyons, Stephen J. O'Brien, Thomas F. Laughlin, Ann T. Bowling, James D. Murray

Biology Faculty Articles

A comparative gene map of the horse genome composed of 127 loci was assembled based on the new assignment of 68 equine type I loci and on data published previously. PCR primers based on consensus gene sequences conserved across mammalian species were used to amplify markers for assigning 68 equine type I loci to 27 horse synteny groups established previously with a horse-mouse somatic cell hybrid panel (SCHP, UC Davis). This increased the number of coding genes mapped to the horse genome by over 2-fold and allowed refinements of the comparative mapping data available for this species. In conjunction with …

Extensive Conservation Of Sex Chromosome Organization Between Cat And Human Revealed By Parallel Radiation Hybrid Mapping, William J. Murphy, Shan Sun, Zhang-Qun Chen, Jill Pecon-Slattery, Stephen J. O'Brien

Biology Faculty Articles

A radiation hybrid (RH)-derived physical map of 25 markers on the feline X chromosome (including 19 Type I coding loci and 6 Type II microsatellite markers) was compared to homologous marker order on the human and mouse X chromosome maps. Complete conservation of synteny and marker order was observed between feline and human X chromosomes, whereas the same markers identified a minimum of seven rearranged syntenic segments between mouse and cat/human X chromosome marker order. Within the blocks, the feline, human, and mouse marker order was strongly conserved. Similarly, Y chromosome locus order was remarkably conserved between cat and human …

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Department of Biology Faculty Publications

The January tetra (Hemigrammus hyanuary Durbin) exhibits two eye color phenotypes. These have a silver iris, which is characteristic of the species, and a green color variant. Segregation patterns observed in the progenies from 12 different crosses support an hypothesis for the monogenic inheritance of iris coloration in this species.

The Role Of Brn-3.2 In Retinal Ganglion Cell Differentiation, Jerin Marie Wright

Loma Linda University Electronic Theses, Dissertations & Projects

Within the retina, the POU domain of transcription factors brn-3.0, brn-3.1, and brn-3.2 are present only in retinal ganglion cells. These genes are believed to be involved in establishing neural cell lineages in mammals. In this study brn-3.2 was examined by comparing the number of ganglion cells present during postnatal development in normal mice (+/+), in mice homozygous (-/-) for the brn-3.2 gene, and in adult mice with a heterozygous gene deletion (+/-) for brn-3.2. Optic nerve cross sections were imaged by electron microscopy, and axon profiles counted systematically by hand. These counts were then related to the nerve cross …

A Preclinical Model Of Ionizing Radiation And Tnf-Alpha Gene Therapy For Cancer, Jun Li

Loma Linda University Electronic Theses, Dissertations & Projects

Long term control of high-grade brain tumors is rarely achieved with current therapeutic regimens. This study sought to determine if pretreatment with plasmid DNA expressing Tumor Necrosis Factor-α (TNF-α) could enhance the effect of ionizing radiation in an aggressive, rapidly growing glioma tumor (C6) model. Plasmid DNA is an attractive vector system for delivery of foreign genes into eukaryotic cells due to its advantages including low immunogenicity in vivo, lesser toxicity and relatively low cost. We have constructed a plasmid-based mammalian expression vector (pGL1-TNF) to secrete human TNF-α from cancer cells. Plasmid DNA was successfully transfected into C6 cells …

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Jack Frankel

Evolutionary Patterns Of Morphometrics, Allozymes And Mitochondrial Dna In Thrashers (Genus Toxostoma), Robert M. Zink, Donna L. Dittmann, John Klicka, Rachelle C. Blackwell-Rago

Ornithology Program (HRC)

We examined patterns of variation in skeletal morphometrics (29 characters), allozymes (34 loci), mitochondrial DNA (mtDNA) restriction sites (n = 74) and fragments (n = 395), and mtDNA sequences (1,739 bp from cytochrome b, ND2, ND6, and the control region) among all species of Toxostoma. The phenetic pattern of variation in skeletal morphometrics generally matched traditional taxonomic groupings (based on plumage patterns) with the exceptions of T. redivivum, which because of its large size clusters outside of its proper evolutionary group (lecontei), and T. occelatum, which did not cluster with T. curvirostre. Skull characters contributed highly to species discrimination, suggesting …

Bridging The Gap Between Life Insurer And Consumer In The Genetic Testing Era: The Rf Proposal, Christopher M. Keefer

Indiana Law Journal

No abstract provided.

Phenotypic Expressions Of Ccr5-Δ32/Δ32 Homozygosity, Giang T. Nguyen, Mary Carrington, Judith A. Beeler, Michael Dean, Louis M. Aledort, Philip M. Blatt, Alan R. Cohen, Donna Dimichele, M. Elaine Eyster, Craig M. Kessler, Barbara Konkle, Cindy Leissinger, Naomi Luban, Stephen J. O'Brien, James J. Goedert, Thomas R. O'Brien

Biology Faculty Articles

Objective: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-Δ32/Δ32 homozygous genotype has phenotypic expressions other than those related to HIV-1.

Design: Study subjects were white homosexual men or men with hemophilia who were not infected with HIV-1. In this study, 15 CCR5-Δ32/Δ32 homozygotes were compared with 201 CCR5 wild-type (+/+) subjects for a wide range of clinical conditions and laboratory assay results ascertained during prospective cohort studies and routine clinical care. CCR5-Δ32 genotype was determined by polymerase chain reaction, followed by single-stranded conformational polymorphism analysis.

Results: …

Evidence Supporting The Recent Origin And Species Status Of The Timberline Sparrow, John Klicka, Robert M. Zink, Jon C. Barlow, W. Bruce Mcgillivray, Terry J. Doyle

Ornithology Program (HRC)

The Timberline Sparrow (Spizella taverneri), although originally described as a species, is currently classified as a subspecies of the more widespread Brewer's Sparrow (S. breweri). We investigated the taxonomic status and recent evolutionary history of these species by comparison of both morphological and molecular characters. Morphometric comparisons using 6 external and 18 skeletal measurements show that S. taverneri specimens from two widely separated populations (Yukon and southwestern Alberta, Canada) are indistinguishable with respect to size yet are significantly larger (by 3%) than representatives of several breweri populations. Analysis of 1,413 base pairs of mitochondrial DNA (mtDNA) for 10 breweri and …

Effects Of Plasma Hiv Rna, Cd4+ T Lymphocytes, And The Chemokine Receptors Ccr5 And Ccr2b On Hiv Disease Progression In Hemophiliacs, Eric S. Daar, Sharyne Donfield, Edward Gomperts, Margaret Hilgartner, Keith Hoots, David Chernoff, Cheryl Winkler, Stephen J. O'Brien, Hemophilia Growth And Development Study

Biology Faculty Articles

We have investigated the effects of plasma HIV RNA, CD4⁺ T lymphocytes and chemokine receptors CCR5 and CCR2b on HIV disease progression in hemophiliacs. We prospectively observed during follow-up 207 HIV-infected hemophiliacs in the Hemophilia Growth and Development Study. Plasma HIV RNA was measured on cryopreserved plasma from enrollment using the Chiron Corporation bDNA (version 2.0) assay. Genotype variants CCR2b-641 and CCR5-Δ32 were detected using standard molecular techniques. Those with the mutant allele for CCR2b, and to a lesser extent CCR5, had lower plasma HIV RNA, and higher CD4⁺ T lymphocytes than did those without these …

The Translocation Of Barramundi. A Discussion Paper., Makaira Pty Ltd

Fisheries management papers

There is recognisable economic benefit to the translocation of barramundi, but there is also a need to ensure the translocation will not adversely impact upon the genetic diversity, introduce disease or impact on the natural environment and biodiversity. This discussion paper has been prepared to provide information to assist in the assessment of the possible impact of translocation of barramundi into and within Western Australia, for the purposed of recreational stock enhancement, aquaculture development and domestic stocking. In contemplating the translocation any aquatic species, signigicant economic and social benefits must be balanced with biological and environmental risks; that is, the …

Dna-Dna Checkerboard Hybridization To Identify Bacteria In Human Plaque Samples, Jasan Lee Zimmerman

Loma Linda University Electronic Theses, Dissertations & Projects

Previous research has shown that using DNA probes to identify the presence of specific bacteria in human plaque samples is superior to the commonly used anaerobic cultural procedures. Some periodontal pathogens are either uncultivable or very difficult to grow, such as Prevotella intermedia, P. nigrescens, and Eubacterium brachy. Digoxygenin probes were prepared for 15 oral bacteria. These probes were used with a checkerboard DNA-DNA hybridization scheme to analyze whether human plaque samples contained any of the 15 bacterial species. Our results have shown that this method is successful in identifying bacterial DNA present in the subgingival patient plaque …

Functional Analysis Of Human Igfbp-6 In Human Osteoblasts, Tao Yan

Loma Linda University Electronic Theses, Dissertations & Projects

Insulin-like growth factor binding proteins (IGFBPs) are a family of six secreted proteins that bind to and modulate the functions of insulin-like growth factors (IGF-I and IGF-II). As a relatively new member of the IGF system, IGFBP-6 was found to be produced by human osteoblasts and exert significant biological effects on human osteoblasts.

Our previous studies indicated that all-trans retinoic acid (ATRA) caused more than a10 fold increase in IGFBP-6 production and a50-60% reduction of ALP activity in human osteoblasts. Based on these findings, we proposed the hypothesis that ATRA induced human osteoblast differentiation was mediated at least in part …

Acute Effects Of Whole-Body Proton Irradiation On The Immune System Of The C57bl/6 Mouse, Eric H. Kajioka

Loma Linda University Electronic Theses, Dissertations & Projects

The acute effects of proton whole-body irradiation (WBI) on leukocytes, lymphocytes, and hematological parameters in the spleen and blood of C57BI/6 mice were examined and compared to the effects of photon (gamma) WBI derived from a 60cobalt (60Co) source. Adult, female C57BL/6 mice were exposed to a single dose (3 Gy, 0.4 Gy/min dose rate) of either proton WBI at the Bragg peak, proton WBI at the entry plateau, or Co WBI, and sacrifice intervals were at 1,4, 7, and 10 days post- WBI. Flow cytometry analysis of the spleen and peripheral blood showed depression in cell counts for all …

Antitumor Effect Of Il-2, P53, And Bax Naked Gene Transfer In C6 Glioma Cells, Peyman Haghighat

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract not included]

Use Of Bioinformatics In The Analysis Of Chemotaxis Proteins, Sean Andrew Bulloch

Loma Linda University Electronic Theses, Dissertations & Projects

Bacterial chemotaxis is one of the best-known signal transduction systems. Levels of attractants and repellents are sensed in the surrounding environment by various chemoreceptors. The signal is passed to the excitation pathway via the transfer of a phosphoryl group from the receptor-associated histidine kinase CheA to the response regulator CheY. Phospho-CheY binds to the flagellar motor switching the direction of rotation of the flagella and thus allowing the cell to move towards or away from the attractant or repellent. The phosphatase CheZ removes the phosphoryl group from phospho-CheY restoring default flagellar rotation. Adaptation to stimuli occurs via addition of methyl …

Engineering Secreted Proteins For Gene Transfer And Dna Vaccination, Jingxue Liu

Loma Linda University Electronic Theses, Dissertations & Projects

In recent years gene therapy has become a promising way of alleviating incurable human ailments, its concept emerging as the ultimate therapy for many infectious and genetic diseases. Two important aspects of the development of successful gene therapy protocols are the ability to monitor gene transfer readily, and the establishment of new protocols for treating specific diseases. In this work, Renilla luciferase and human glutamic acid decarboxylase (GAD) 65 were engineered for secretion to address some aspects of these issues.

Secreted reporter proteins are promising tools to study gene transfer and expression in a non-destructive manner, and bioluminescent proteins are …

The Timing Oflin-4rna Accumulation Controls The Timing Of Postembryonic Developmental Events Incaenorhabditis Elegans, Rhonda Feinbaum, Victor Ambros

Victor R. Ambros

The lin-4 gene encodes a small RNA that is required to translationally repress lin-14 toward the end of the first larval stage of Caenorhabditis elegans development. To determine if the timing of LIN-14 protein down-regulation depends on the temporal profile of lin-4 RNA level, we analyzed the stage-specificity of lin-4 RNA expression during wild-type development and examined the phenotypes of transgenic worms that overexpress lin-4 RNA during the first larval stage. We found that lin-4 RNA first becomes detectable at approximately 12 h of wild-type larval development and rapidly accumulates to nearly maximum levels by 16 h. This profile of …

Cbfa2 Is Required For The Formation Of Intra-Aortic Hematopoietic Clusters, Trista North, Ting-Lei Gu, Stacy Terryl, Qing Wang, Louisa Howard, Michael Binder, Miguel Marín-Padilla, Nancy A. Speck

Dartmouth Scholarship

Cbfa2 (AML1) encodes the DNA-binding subunit of a transcription factor in the small family of core-binding factors (CBFs). Cbfa2 is required for the differentiation of all definitive hematopoietic cells, but not for primitive erythropoiesis. Here we show that Cbfa2 is expressed in definitive hematopoietic progenitor cells, and in endothelial cells in sites from which these hematopoietic cells are thought to emerge. Endothelial cells expressing Cbfa2 are in the yolk sac, the vitelline and umbilical arteries, and in the ventral aspect of the dorsal aorta in the aorta/genital ridge/mesonephros (AGM) region. Endothelial cells lining the dorsal aspect of the aorta, and …

Genetic Consequences Of Mammalian Social Structure, Jay F. Storz

Jay F. Storz Publications

Populations of social mammals are characterized by several demographic features that may increase the magnitude of genetic drift relative to other evolutionary forces. In particular, polygynous mating and socially mediated constraints on gene flow have been proposed to foster random genetic differentiation among social groups, thereby accelerating rates of evolutionary change. To evaluate this hypothesized link between sociality and genetic sub- division, I examined results of published studies of mammalian populations in which genetic structuring was assessed at the level of social groups. Population genetic data from a taxonomically diverse array of social mammals revealed low to moderately high levels …

Cell Cycle-Dependent Sequencing Of Cell Fate Decisions In Caenorhabditis Elegans Vulva Precursor Cells, Victor Ambros

Victor R. Ambros

In Caenorhabditis elegans, the fates of the six multipotent vulva precursor cells (VPCs) are specified by extracellular signals. One VPC expresses the primary (1 degrees ) fate in response to a Ras-mediated inductive signal from the gonad. The two VPCs flanking the 1 degrees cell each express secondary (2 degrees ) fates in response to lin-12-mediated lateral signaling. The remaining three VPCs each adopt the non-vulval tertiary (3 degrees ) fate. Here I describe experiments examining how the selection of these vulval fates is affected by cell cycle arrest and cell cycle-restricted lin-12 activity. The results suggest that lin-12 participates …

Amplification Of The Phenol Hydroxylase Promoter Region Of Pseudomonas Putida Cf600 As A Precursor For Transcriptional Fusion, Priya Bhat

Honors Capstone Projects and Theses

No abstract provided.

Balancing Interests In Frozen Embryo Disputes: Is Adoption Really A Reasonable Alternative?, David L. Theyssen

Indiana Law Journal

No abstract provided.

Interpreting Patterns Of Gene Expression With Self-Organizing Maps: Methods And Application To Hematopoietic Differentiation, Pablo Tamayo, Donna Slonim, Jill Mesirov, Qing Zhu, Sutisak Kitareewan, Ethan Dmitrovsky

Dartmouth Scholarship

Array technologies have made it straightforward to monitor simultaneously the expression pattern of thousands of genes. The challenge now is to interpret such massive data sets. The first step is to extract the fundamental patterns of gene expression inherent in the data. This paper describes the application of self-organizing maps, a type of mathematical cluster analysis that is particularly well suited for recognizing and classifying features in complex, multidimensional data. The method has been implemented in a publicly available computer package, GENECLUSTER, that performs the analytical calculations and provides easy data visualization. To illustrate the value of such analysis, the …

The Dna Helicase Activity Of Blm Is Necessary For The Correction Of The Genomic Instability Of Bloom Syndrome Cells, Norma F. Neff, Nathan A. Ellis, Tian Zhang Ye, James Noonan, Kelly Huang, Maureen M. Sanz, Maria Proytcheva

Faculty Works: Biology, Chemistry, and Environmental Studies

Bloom syndrome (BS) is a rare autosomal recessive disorder characterized by growth deficiency, immunodeficiency, genomic instability, and the early development of cancers of many types. BLM, the protein encoded by BLM, the gene mutated in BS, is localized in nuclear foci and absent from BS cells. BLM encodes a DNA helicase, and proteins from three missense alleles lack displacement activity. BLM transfected into BS cells reduces the frequency of sister chromatid exchanges and restores BLM in the nucleus. Missense alleles fail to reduce the sister chromatid exchanges in transfected BS cells or restore the normal nuclear pattern. BLM complements a …

Trends. Altered States And Genetically Altered Products: Psychological Crisis At Cartagena, Ibpp Editor

International Bulletin of Political Psychology

The author discusses the first comprehensive attempt to develop a global treaty that would regulate commerce in genetically altered products.

Genome-Wide Bioinformatic And Molecular Analysis Of Introns In Saccharomyces Cerevisiae, Marc Spingola, Leslie Grate, David Haussler, Manuel Ares

Biology Department Faculty Works

Introns have typically been discovered in an ad hoc fashion: introns are found as a gene is characterized for other reasons. As complete eukaryotic genome sequences become available, better methods for predicting RNA processing signals in raw sequence will be necessary in order to discover genes and predict their expression. Here we present a catalog of 228 yeast introns, arrived at through a combination of bioinformatic and molecular analysis. Introns annotated in the Saccharomyces Genome Database (SGD) were evaluated, questionable introns were removed after failing a test for splicing in vivo, and known introns absent from the SGD annotation were …

Genome-Wide Bioinformatic And Molecular Analysis Of Introns In Saccharomyces Cerevisiae, Marc Spingola, Leslie Grate, David Haussler, Manuel Ares

Marc Spingola