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Melanocortin-1-Receptor (Mcr-1) Gene Polymorphisms Associated With The Chicken E Locus Alleles, Andrew Ellett

Inquiry: The University of Arkansas Undergraduate Research Journal

The melanocortin 1-receptor (MCl-R) gene has been associated with E locus phenotypes in chickens. Variant alleles of the E locus are important for accurate down color sexing and also for the inhibition of unwanted tissue pigmentation in broilers. PCR (polymerase chain reaction) based tests for various replacement substitutions found in the published E allele sequences gave unexpected results when tested against known alleles of the E locus. To resolve these issues and gain a better understanding of how replacement substitutions in the MCl-R gene are affecting E locus phenotypes, a number of accessions of the e+, eb, wheaten ( ewh …

The Holliday Junction In An Inverted Repeat Dna Sequence: Sequence Effects On The Structure Of Four-Way Junctions, Brandt F. Eichman, Jeff Vargason, Blaine H.M. Mooers, P. Shing Ho

Faculty Publications - Department of Biological & Molecular Science

Holliday junctions are important structural intermediates in recombination, viral integration, and DNA repair. We present here the single-crystal structure of the inverted repeat sequence d(CCGGTACCGG) as a Holliday junction at the nominal resolution of 2.1 Å. Unlike the previous crystal structures, this DNA junction has B-DNA arms with all standard Watson–Crick base pairs; it therefore represents the intermediate proposed by Holliday as being involved in homologous recombination. The junction is in the stacked-X conformation, with two interconnected duplexes formed by coaxially stacked arms, and is crossed at an angle of 41.4° as a right-handed X. A sequence comparison with previous …

Eph Receptors And Ephrins, Masaru Nakamoto

Biology Faculty Publications

The Eph receptors are the largest known family of receptor tyrosine kinases. The Eph receptors and theirmembrane-attached ligands, ephrins, show diverse expression patterns during development. Recent studies havedemonstrated that Eph receptors and ephrins play important roles in many developmental processes, includingneuronal network formation, the patterning of the neural tube and the paraxial mesoderm, the guidance of cellmigration, and vascular formation. In the nervous system, Eph receptors and ephrins have been shown to act aspositional labels to establish topographic projections. They also play a key role in pathway ®nding by axons andneural crest cells. The crucial roles of Eph receptors and …

Detection And Modeling Of Radiation Induced Effects In Tissues By Dielectric Spectroscopy, Dorin A. Todor

Physics Theses & Dissertations

The work presented here is applied physics research in the field of radiation treatment. We address the development of a new and innovative method, in vivo and possibly non-invasive, for tumor and healthy tissues control during and after the radiation treatment. The radiation treatment is delivered in an almost standardized manner for particular classes of tumors. The large variance in the individual radio sensitivity of healthy tissues and tumors often leads to local recurrence of neoplastic growth and/or distant metastatic disease which often remains untreated. The method is based on the measurement and analysis of electrical impedance data in …

Cytotoxic T Cell Response To Influenza Vaccination In Older Adults, Caroline R. Letter

Chemistry & Biochemistry Theses & Dissertations

Influenza infections result in activation of cellular and humoral immune responses, leading to stimulation of cytotoxic T cells (CTL) and helper T cells with subsequent viral clearance.

By using an assay of granzyme B activity, the in vivo cellular-mediated immune response of old adults was found to be significantly decreased in comparison to young adults. The effect of aging on the CTL response was further investigated via enzyme-linked immunospot technique. A significant increase in number of virus-specific T cells occurred in older adults after vaccination, although the magnitude of the CTL response decreased in comparison to young adults. These data …

Biochemical Composition Of Particles And Dissolved Organic Matter Slong An Estuarine Gradient: Sources And Implications For Dom Reactivity, Antonio Mannino, H. Rodger Harvey

OES Faculty Publications

The chemical composition of high molecular weight dissolved organic matter (DOM) and particulate organic matter (POM) was examined along the salinity gradient of the Delaware Estuary. DOM was collected and fractionated by tangential-flow ultrafiltration into 1-30 kDa (HDOM; high molecular weight) and 30 kDa to 0.2 μm (VHDOM; very high molecular weight) and compared to particles collected in parallel. Polysaccharides comprised 12-43% of particulate organic carbon (POC), 30-56% of VHDOM carbon, and 7.5-19% of HDOM carbon. Hydrolyzable amino acids comprised 17-38% of POC, 5.4-12% of VHDOM carbon, and 1.5-4.2% of HDOM carbon. Only 7-43% of dissolved organic nitrogen in VHDOM …

Absence Of Insect Juvenile Hormones In The American Dog Tick, Dermacentor Veriabilis (Say) (Acari: Ixodidae), And In Ornithodoros Parkeri Cooley (Acari: Argasidae), P. A. Neese, Daniel E. Sonenshine, V. L. Kallapur, C. S. Apperson, R. M. Roe

Biological Sciences Faculty Publications

Synganglia, salivary gland, midgut, ovary, fat body and muscle alone and in combination from the ixodid tick, Dermacentor variabilis (Say), or the argasid tick, Ornithodoros parkeri Cooley, were incubated in vitro in separate experiments with _L-[methyl-³H]methionine and farnesoic acid or with [1-¹⁴C]acetate. Life stages examined in D. variabilis were 3 and 72 h old (after ecdysis) unfed nymphs, partially fed nymphs (18 and 72 h after attachment to the host), fully engorged nymphs (2 d after detachment from host), 3 and 72 h old (after eclosion) unfed females, partially fed unmated females (12–168 …

Isovolumic Regulation In Nervous Tissue: A Novel Mechanism Of Cell Volume Regulation, O. Quesada, R. Franco, K. Hernandez-Fonseca, K. Tuz

School of Veterinary and Biomedical Sciences: Faculty Publications

Cell volume regulation is a property present in most animal cell lineages that allows them to recover their original volume after events of swelling or shrinkage. Such events can be caused by changes in external osmolarity or to osmotic gradients generated during normal cell functioning.4,6 The mechanism of cell volume regulation involves transmembrane fluxes of osmotically active solutes in the necessary direction to counteract the net gain or loss of intracellular water.9 The process through which cells recover their normal volume after swelling is named Regulatory Volume Decrease (RVD). This consists of the efflux of inorganic osmolytes, such as K …

Rbcs Suppressor Mutations Improve The Thermal Stability And Co2/O2 Specificity Of Rbcl-Mutant Ribulose-1,5-Bisphosphate Carboxylaseyoxygenase, Yu-Chan Du, Seokjoo Hong, Robert J. Spreitzer

Department of Biochemistry: Faculty Publications

In the green alga Chlamydomonas reinhardtii, a Leu²⁹⁰-to-Phe (L²⁹⁰F) substitution in the large subunit of ribulose-1,5-bisphosphate carboxylaseyoxygenase (Rubisco), which is coded by the chloroplast rbcL gene, was previously found to be suppressed by second-site Ala222-to-Thr and Val²⁶²-to-Leu substitutions. These substitutions complement the photosynthesis deficiency of the L290F mutant by restoring the decreased thermal stability, catalytic efficiency, and CO₂/O₂ specificity of the mutant enzyme back to wild-type values. Because residues 222, 262, and 290 interact with the loop between β strands A and B of the Rubisco small subunit, which is …

Multiple Factors Independently Regulate Hila And Invasion Gene Expression In Salmonella Enterica Serovar Typhimurium, Robin L. Lucas, C. Phoebe Lostroh, Concetta C. Dirusso, Michael P. Spector, Barry L. Wanner, Catherine A. Lee

Department of Biochemistry: Faculty Publications

HilA activates the expression of Salmonella enterica serovar Typhimurium invasion genes. To learn more

about regulation of hilA, we isolated Tn5 mutants exhibiting reduced hilA and/or invasion gene expression. In

addition to expected mutations, we identified Tn5 insertions in pstS, fadD, flhD, flhC, and fliA. Analysis of the

pstS mutant indicates that hilA and invasion genes are repressed by the response regulator PhoB in the absence

of the Pst high-affinity inorganic phosphate uptake system. This system is required for negative control of the

PhoR-PhoB two-component regulatory system, suggesting that hilA expression may …

Multiple Factors Independently Regulate Hila And Invasion Gene Expression In Salmonella Enterica Serovar Typhimurium, Robin L. Lucas, C. Phoebe Lostroh, Concetta C. Dirusso, Michael P. Spector, Barry L. Wanner, Catherine A. Lee

Department of Biochemistry: Faculty Publications

HilA activates the expression of Salmonella enterica serovar Typhimurium invasion genes. To learn more

about regulation of hilA, we isolated Tn5 mutants exhibiting reduced hilA and/or invasion gene expression. In

addition to expected mutations, we identified Tn5 insertions in pstS, fadD, flhD, flhC, and fliA. Analysis of the

pstS mutant indicates that hilA and invasion genes are repressed by the response regulator PhoB in the absence

of the Pst high-affinity inorganic phosphate uptake system. This system is required for negative control of the

PhoR-PhoB two-component regulatory system, suggesting that hilA expression may …

Two-Step Processing Of Human Frataxin By Mitochondrial Processing Peptidase, Patrizia Cavadini, Jiri Adamec, Franco Taroni, Oleksandr Gakh, Grazia Isaya

Department of Biochemistry: Faculty Publications

We showed previously that maturation of the human

frataxin precursor (p-fxn) involves two cleavages by the

mitochondrial processing peptidase (MPP). This observation

was not confirmed by another group, however,

who reported only one cleavage. Here, we demonstrate

conclusively that MPP cleaves p-fxn in two sequential

steps, yielding a 18,826-Da intermediate (i-fxn) and a

17,255-Da mature (m-fxn) form, the latter corresponding

to endogenous frataxin in human tissues. The two cleavages

occur between residues 41–42 and 55–56, and both

match the MPP consensus sequence RX ↓ (X/S). Recombinant

rat and yeast MPP catalyze the pài step 4 and 40 …

Job Compensation In The Biotechnology Core Laboratory, Debra A. Mcmillen, William M. Old, Janice L. Bleibaum, Charles M. Nicolet, Katheryn R. Resing, Gautam Sarath, Satya P. Yadav

Gautam Sarath Publications

The results of a poll of core facility professionals by the Association of Biomolecular Resource Facilities (ABRF) Survey Committee.

Urea Hydrolysis Using Immobilized Urease, Anita Arullan

Student Works (2000-2009)

An inexpensive carrier matrix. vermiculite was used for immobilizing urease. A cost effective and simple method of coupling was developed using vermiculite. Immobilization of urease on Amberlite MB-land Nylon-6 tube were also studied. Activities of free and immobilized urease were studied and compared: Among all methods used for immobilization of urease. the method of coupling the enzyme to vermiculite gave the highest retained activity of 82% (Method I) and 89% (Method 2) at pH 6.0 and 5.5 respectively. Urease immobilized by Method I retained 69% and 30% of its original activity and Method 2 (using glutaraldehyde as coupling agent) retained …

Typical Friedreich’S Ataxia Without Gaa Expansions And Gaa Epansions Wthout Typical Friedreich’S Ataxia, Dominick Mccabe, Fergus Ryan, D. Moore, Shirley Mcquaid, M. King, A. Kelly, K. Daly, David Barton, R. Murphy

Articles

We clinically assessed and performed polymerase chain reaction analysis for the GAA trinucleotide repeat expansion in 103 patients from 73 families in Ireland, with a prior clinical diagnosis of Friedreich’s ataxia (FA) or an unclassified progressive ataxic syndrome. The patients were classified as “typical” or “atypical” FA according to Harding’s mandatory clinical diagnostic criteria. All patients underwent blood glucose analysis, and electrocardiography and echocardiography was performed in 99 and 101 patients, respectively. Mutation screening for expanded CAG trinucleotide repeats, associated with spinocerebellar ataxia (SCA) 1, 2, 3 and 6 was performed in 86 patients overall, including all GAA negative patients. …

Use Of Oak Hammocks By Neotropical Migrant Songbirds During Stopover In Coastal South Carolina, Scott Glen Somershoe

College of Graduate Studies: Theses & Dissertations (1964–2006)

Many species of Neotropical migrant songbirds have been reported to be declining in the last few decades, and the loss and fragmentation of stopover habitat has been implicated as a potential cause of these population declines. To manage properly a fragmented forest landscape for migrating songbirds information is needed on how the size and the habitat of forest fragments influence their use by migrants during stopover. Therefore, I conducted censuses of Neotropical migrant birds in eight oak hammocks of varying size (0.32-3.08 ha) at the Savannah National Wildlife Refuge, Jasper County, South Carolina. Censuses were conducted at 0600-1030 h during …

The Abundance And Distribution Of Arthropods From Sandstone Outcrops In Coffee County, Georgia, F. Michael Mcaloon

College of Graduate Studies: Theses & Dissertations (1964–2006)

Broxton Rocks Nature Preserve, a 1,233-hectare preserve containing late Pleistocene sandstone (Altamaha grit) outcrops of various sizes and topographies in a conifer-dominated loblolly pine - hardwood forest, represents a unique habitat to the coastal plain of Georgia. Using modified pitfall traps, I sampled arthropods in four subhabitats (bare rock, lichens, ecotone, wiregrass) at Broxton Rocks between January and November 1999. A total of 312,006 arthropods belonging to four classes (Arachnida, Diplopoda, Chilopoda, Insecta) represented by 24 orders was trapped. The numbers of arthropods varied among habitat types, and over the collection dates (P

The Effects Of Low Ph On Sunfish Assemblages In Southeast Georgia, William Boyd Tate

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.

Effects Of Height And Vegetation On Success Of Bird Nests In Maritime Forests, Sharon M. Defalco

College of Graduate Studies: Theses & Dissertations (1964–2006)

Nest predation is an important source of mortality in songbirds and may contribute to declines in Neotropical migrants. I used artificial nests baited with fresh Japanese Quail and Zebra Finch eggs in conjunction with observations of natural nests to quantity the ettects ol nest height and vegetation on nest predation on St. Catherine's Island, a barrier island in southeast Georgia. Because of intense browsing by white-tailed deer. I predicted that lower, more exposed nests would be least successful. Artificial nests (n = 389) were placed in the field, and natural nests (n = 49) were observed, durintz April and May …

Cloning And Sequencing Of Sodium-Hydrogen Exchanger In The Gills Of The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Danielle Lee Gunning

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.

Applications Of The Atomic Force Microscope Within The Fields Of Haematology And Cytogenetics, Margaret O'Reilly-Crowley

Theses

Atomic force microscopy [AFM] has become a rapidly developing interdisciplinary field of research in recent years. The technique, including instrumentation and specimen preparation methods, is now more sophisticated and its application has increased dramatically. The key advantage of AFM is in providing three-dimensional images of samples imaged. Both size and shape of samples imaged can be obtained allowing their subsequent quantification. Red blood cells [RBCs] and chromosomes were imaged in this work. A brief overview of the current status of biomedical AFM, has been presented in the review.

Measurement of mean cell volume [MCV] of immobilised red blood cells with …

Human Gonadotropin-Releasing Hormone (Hgnrh) Gene Expression And Hormone Regulation In Human Placental Jeg-3 Cells, Heming Zheng

Theses and Dissertations in Biomedical Sciences

Using the human placental choriocarcinoma JEG-3 cell line as an in vitro human placental model, I studied the mechanisms of the tissue-specific expression and steroid hormone regulation of the hGnRH gene in the human placenta. The results showed that all of the previously identified four elements are required for the full activity of the hGnRH upstream promoter in JEG-3 cells, while the element 4 (FP4, −987/−968) is the most important. Studies performed with 5′ end deletion of this region confirmed these observations. Further, supershift assay using Oct-1 antibody demonstrated the involvement of Oct-1 in the FP4 DNA-protein interaction in JEG-3 …

Structure And Function Analysis Of Lin-14, A Temporal Regulator Of Postembryonic Developmental Events In Caenorhabditis Elegans, Yang Hong, Rosalind C. Lee, Victor Ambros

Dartmouth Scholarship

During postembryonic development of Caenorhabditis elegans, the heterochronic gene lin-14 controls the timing of developmental events in diverse cell types. Three alternativelin-14 transcripts are predicted to encode isoforms of a novel nuclear protein that differ in their amino-terminal domains. In this paper, we report that the alternative amino-terminal domains of LIN-14 are dispensable and that a carboxy-terminal region within exons 9 to 13 is necessary and sufficient for in vivo LIN-14 function. A transgene capable of expressing only one of the three alternativelin-14 gene products rescues a lin-14 null mutation and is developmentally regulated by lin-4. …

Emissions Of Formaldehyde, Acetic Acid, Methanol, And Other Trace Gases From Biomass Fires In North Carolina Measured By Airborne Fourier Transform Infrared Spectroscopy, Robert J. Yokelson, Jon G. Goode, Darold E. Ward, Ronald A. Susott, Ronald E. Babbitt, D. D. Wade, Issac T. Bertschi, David W. T. Griffith, Wei Min Hao

Chemistry and Biochemistry Faculty Publications

Biomass burning is an important source of many trace gases in the global troposphere. We have constructed an airborne trace gas measurement system consisting of a Fourier transform infrared spectrometer (FTIR) coupled to a “flow-through” multipass cell (AFTIR) and installed it on a U.S. Department of Agriculture Forest Service King Air B-90. The first measurements with the new system were conducted in North Carolina during April 1997 on large, isolated biomass fire plumes. Simultaneous measurements included Global Positioning System (GPS); airborne sonde; particle light scattering, CO, and CO₂; and integrated filter and canister samples. AFTIR spectra acquired within …

Biochemical And Biophysical Analysis Of The Intracellular Lipid Binding Proteins Of Adipocytes, Melanie A. Simpson, Vince J. Licata, Natalie Ribarik Coe, David A. Bernlohr

Department of Biochemistry: Faculty Publications

Adipocytes express two lipid-binding proteins; the major one termed the adipocyte lipid-binding protein or aP2 (ALBP/aP2) and a minor one referred to as the keratinocyte lipid-binding protein (KLBP). In order to evaluate the potential physiological roles for these proteins, their biochemical and biophysical properties have been analyzed and compared. ALBP/aP2 and KLBP exhibit similar binding affinities for most long-chain fatty acids; however, ALBP/aP2 exhibits a two to three-fold increased affi nity for myristic, palmitic, oleic and linoleic acids, the predominant fatty acids of adipocytes. As measured by guanidinium hydrochloride denaturation, the stability of ALBP/aP2 is nearly 3 kcal/mol greater than …

Melanoma Chondroitin Sulphate Proteoglycan Regulates Cell Spreading Through Cdc42, Ack-1 And P130Cas, Kathryn M. Eisenmann, James B. Mccarthy, Melanie A. Simpson, Patricia J. Keely, Jun-Lin Guan, Kouichi Tachibana, Louis Lim, Ed Manser, Leo T. Furcht, Joji Iida

Department of Biochemistry: Faculty Publications

Melanoma chondroitin sulphate proteoglycan (MCSP) is a cell-surface antigen that has been implicated in the growth and invasion of melanoma tumors. Although this antigen is expressed early in melanoma progression, its biological function is unknown. MCSP can stimulate the integrin-α4β1-mediated adhesion and spreading of melanoma cells. Here we show that stimulated MCSP recruits tyrosine- phosphorylated p130cas, an adaptor protein important in tumor cell motility and invasion. MCSP stimulation also results in a pronounced activation and recruitment of the Rho-family GTPase Cdc42. MCSP-induced spreading of melanoma cells is dependent upon active Cdc42, a Cdc42-associated tyrosine kinase (Ack-1) and tyrosine phosphorylation of …

Three-Dimensional Structure Of The Gly121tyr Dimeric Form Of Ornithine Decarboxylase From Lactobacillus 30a, Jacqueline Vitali, Donald Carroll, Rochika G. Chaudhrya, Marvin L. Hackert

Physics Faculty Publications

Ornithine decarboxylases catalyze the conversion of ornithine to putrescine at the beginning of the polyamine pathway. Ornithine decarboxylase (ODC) from Lactobacillus 30a is a 990612 Da dodecamer composed of six homodimers. A single point mutation (Gly121Tyr) was found to prevent association of dimers into dodecamers. The dimeric protein has been crystallized at pH 7.0 in the presence of guanosine triphosphate (GTP). Crystals belong to space group P3₂21, with unit-cell parameters a = 111.8, c = 135.9 Å and one monomer in the asymmetric unit. The structure was determined by molecular replacement and refined using simulated annealing to …

Structural Studies Of Recombinant Human Β-Casein Proteins, Yilin Hu

Loma Linda University Electronic Theses, Dissertations & Projects

β-Casein is the major component (~80%) of the human casein system. Interacting with calcium and phosphates through its phosphorylated N-terminus, β-casein participates in the formation of micelles which carry these otherwise insoluble nutrients indispensable for the growth and development of newborns. Human β-casein, or fragments thereof, are also found to have biological effects such as enhancement of calcium absorption. So far, knowledge of micelle formation is limited and structural studies of β-casein, especially its N-terminal portion will provide a better understanding of the structure-function relationship of milk micelles.

To elucidate the role that the N-terminus of the protein plays in …

New Mammalian Selenocysteine-Containing Proteins Identified With An Algorithm That Searches For Selenocysteine Insertion Sequence Elements, Gregory V. Kryukov, Valentin M. Kryukov, Vadim N. Gladyshev

Vadim Gladyshev Publications

Mammalian selenium-containing proteins identified thus far contain selenium in the form of a selenocysteine residue encoded by UGA. These proteins lack common amino acid sequence motifs, but 3’-untranslated regions of selenoprotein genes contain a common stem-loop structure, selenocysteine insertion sequence (SECIS) element, that is necessary for decoding UGA as selenocysteine rather than a stop signal. We describe here a computer program, SECISearch, that identifies mammalian selenoprotein genes by recognizing SECIS elements on the basis of their primary and secondary structures and free energy requirements. When SECISearch was applied to search human dbEST, two new mammalian selenoproteins, designated SelT and SelR, …

Sec34p, A Protein Required For Vesicle Tethering To The Yeast Golgi Apparatus, Is In A Complex With Sec35p, Susan M. Vanrheenen, Xiaochun Cao, Stephanie K. Sapperstein, Elbert C. Chiang, Vladimir V. Lupashin, Charles Barlowe, M. Gerard Waters

Dartmouth Scholarship

A screen for mutants of Saccharomyces cerevisiae secretory pathway components previously yielded sec34, a mutant that accumulates numerous vesicles and fails to transport proteins from the ER to the Golgi complex at the restrictive temperature (Wuestehube, L.J., R. Duden, A. Eun, S. Hamamoto, P. Korn, R. Ram, and R. Schekman. 1996. Genetics. 142:393–406). We find that SEC34 encodes a novel protein of 93-kD, peripherally associated with membranes. The temperature-sensitive phenotype of sec34-2 is suppressed by the rab GTPase Ypt1p that functions early in the secretory pathway, or by the dominant form of the ER to Golgi complex target-SNARE …