Life Sciences Commons^™

Book Review Of "Of Flies, Mice, And Men: On The Revolution In Molecular Biology, By One Of The Scientists Who Helped Make It" By François Jacob, Nancy Curtis

Library Staff Publications

No abstract provided.

Testosterone Effects On Renal Norepinephrine Content And Release In Rats With Different Y Chromosomes, Thomas J. Jones, Gail Dunphy, Amy Milsted, Daniel Ely

Biology Faculty Research

The Y chromosome in spontaneously hypertensive rats (SHR) and stroke-prone rats has been shown to contain a locus that contributes to the hypertensive effect; both the sympathetic nervous system and testosterone may be involved. The objective of this study was to look at the effects of testosterone on renal norepinephrine (NE) release and content in the isolated perfused kidney in different Y chromosome backgrounds. The study involved male SHR, Wistar-Kyoto rats (WKY), and 2 consomic strains with different Y chromosomes (n=5 to 8 per group). Adult animals were castrated, and implants containing testosterone propionate were placed at the base of …

Heritability Of Expression Of The 70kd Heat-Shock Protein In Drosophila Melanogaster And Its Relevance To The Evolution Of Thermotolerance, Robert A. Krebs, Martin E. Feder, Jeehyun Lee

Biological, Geological, and Environmental Faculty Publications

The principle inducible heat-shock protein of Drosophila melanogasrer, Hsp70, contributes to thermotolerance throughout the entire life cycle of the species but may also reduce fitness in some life stages. In principle, selection might maximize the benefits of Hsp70 expression relative to its costs by adjusting the magnitude of Hsp70 expression for each life-cycle stage independently. Therefore we examined whether the magnitude of Hsp70 ex pre sion varied during the life cycle and the relationship of this variation to several life-history traits. For 28 isofemale lines derived from a single natural population, estimates of heritable variation in Hsp70 expression ranged between …

Obesity: Environment Vs. Genetics, Kammi Marie Reeder Hansen

Undergraduate Honors Capstone Projects

The prevalence of overweight and obese individuals is rising. Between 1980 and 1990 there was an 8% increase in the prevalence of obesity. Obesity is associated with many diseases such as hypertension, type 2 diabetes, heart disease and cancer. Over $39 billion dollars is spent annually on the illnesses associated with obesity. Our American culture has been blamed for the rise in obesity, yet there are obviously many people living in the American culture that are not obese. Researchers have turned to genetics to explain this phenomenon. This article will examine the many environmental factors that contribute to obesity and …

Intracellular Coexpression Of Epidermal Growth Factor Receptor, Her-2/Neu, And P21ras In Human Breast Cancers: Evidence For The Existence Of Distinctive Patterns Of Genetic Evolution That Are Common To Tumors From Different Patients, Stanley E. Shackney, Agnese A. Pollice, Charles A. Smith, Laura E. Janocko, Lillian Sweeney, Kathryn A. Brown, Sarita G. Singh, Lingping Gu, Robert Yakulis, Joseph F. Lucke

Joseph Lucke

Multiparameter flow cytometry studies were performed on cells from the primary tumors of 94 patients with breast cancer. Correlated cellular measurements of cell DNA content, Her-2/neu, epidermal growth factor receptor (EGFR), and p21ras levels were performed on each of 5,000 to 100,000 cells from each tumor. When criteria for positivity were matched with those in common use for immunohistochemical studies, 28 of 94 (30\%) breast cancers were classified as positive for Her-2/neu overexpression. When similar criteria were applied to the EGFR measurements, 23 of 94 (24\%) cases were classified as positive for EGFR overexpression. Similarly, 23 of 94 (24\%) cases …

Evolutionary Genetics And Genetic Variation Of Haplodiploids And X-Linked Genes, Philip W. Hedrick, Joel D. Parker

Joel D Parker

The evolutionary genetics of haplodiploids and X-linked genes share many features and are different from diploid (autosomal) genes in many respects. For example, the conditions for a stable polymorphism, the amount of genetic load, and the effective population size are all expected to be quite different between haplodiploids or X-linked genes and diploids. From experimental data, the genetic load for X-linked genes is much less than autosomal genes and appears less for haplodiploids than for diploids. The observed amount of molecular variation for haplodiploids is much less than that for diploids, even more so than predicted from the differences in …

Cancer Genetic Susceptibility Testing: Ethical And Policy Implications For Future Research And Clinical Practice, Benjamin S. Wilfond, Karen H. Rothenberg, Elizabeth J. Thomson, Caryn Lerman

Faculty Scholarship

No abstract provided.

Homology Among The Autosomal Chromosomes Of Boophilus Annulatus (Say) And B. Microplus (Canestrini), Bonnie S. Gunn

Theses and Dissertations - UTB/UTPA

Autosomes of Boophilus annulatus and B. microplus were compared using C- and G-bands to establish the degree of homology. Karyotypes of both species consisted of 20 autosomes and an XX:XO sex determination system with the X being the largest chromosome. All chromosomes of B. annulatus were acrocentric with heterochromatin limited to centromeric regions. The B. microplus karyotype was acrocentric with one band of noncentromeric heterochromatin occurring in three chromosome pairs. Interspecific comparisons indicated seven pairs of G-band homologous autosomes and three G-band homologous pairs when added interstitial heterochromatin was considered. The number three chromosome of both species showed variation in …

Evolutionary Genetics Of Canyon Treefrogs (Hyla Arenicolor), Roy A. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population genetics is the study of the mechanisms that cause genetic change in populations over time. Genetic changes may lead to both adaptive evolution and speciation. While the former process is fairly well understood, many questions remain unanswered with regard to the process of speciation. How important is population isolation in the process of speciation? How long must populations be isolated before speciation is complete? Are the genetic changes that take place during speciation caused mainly by natural selection or does genetic drift play a substantial role? Can genetic drift alone lead to reproductive isolation? These types of questions have …

Genetic Information And The Workplace: Legislative Approaches And Policy Challenges, Karen H. Rothenberg, Barbara Fuller, Mark Rothstein, Troy Duster, Mary Jo Ellis Kahn, Rita Cunningham, Beth Fine, Kathy Hudson, Mary-Claire King, Patricia Murphy, Gary Swergold, Francis Collins

Faculty Scholarship

No abstract provided.

The Rdna Internal Transcribed Spacer Region As A Taxonomic Marker For Nematodes, Thomas O. Powers, T. C. Todd, A. M. Burnell, P. C. B. Murray, C. C. Flemming, Allen L. Szalanski, B. A. Adams, T. S. Harris

Department of Plant Pathology: Faculty Publications

The ITS region from a wide taxonomic range of nematodes, including secernentean and adenophorean taxa, and free-living, entomopathogenic, and plant-parasitic species, was evaluated as a taxonomic marker. Size of the amplified product aided in the initial determination of group membership, and also suggested groups that may require taxonomic reevaluation. Congeneric species often displayed identically sized ITS regions, but genera such as Pratylenchus and Tylenchorhynchus had species with large differences in size. ITS heterogeneity in individuals and populations was identified in several nematode taxa. PCR-RFLP of ITS1 is advocated as a method of taxonomic analysis in genera such as Helicotylenchus that …

The Silviculture-Wood Quality Connection In Eastern Black Walnut, Douglas D. Stokke, Bruce E. Cutter, John E. Phelps

Douglas D. Stokke

The known effects of silvicultural practices on eastern black walnut (Juglans nigra L.) wood quality are reviewed. Since desirable quality differs from end user to end user, no specific recommendations are made.

Discrimination Of Species In The Montastrea Annularis Complex Using Multiple Genetic Loci, Jose V. Lopez, Nancy Knowlton

Marine & Environmental Sciences Faculty Articles

Montastraea annularis, M. franksi and M. faveolata are a complex of recently distinguished coral species whose status remains controversial due to the lack of fixed differences. Here we report on two types of genetic analyses for these taxa: 1) DNA sequences of two nuclear genes [internal transcribed spacers of rDNA (ITS-1, ITS-2) and a ɮ-tubulin intron] and 2) a preliminary screening of the entire nuclear genome using amplified fragment length polymorphisms (AFLP). There was very little variation within or among the three species in DNA sequences. Onlly 3 of 300 nucleotide positions in ITS-1, 3 of the 350 positions …

The Product Of The Saccharomyces Cerevisiae Rss1 Gene, Identified As A High-Copy Suppressor Of The Rat7-1 Temperature-Sensitive Allele Of The Rat7/Nup159 Nucleoporin, Is Required For Efficient Mrna Export, Veronica Del Priore, Christine A. Snay, Andre Bahr, Charles N. Cole

Dartmouth Scholarship

RAT7/NUP159 was identified previously in a screen for genes whose products are important for nucleocytoplasmic export of poly(A)+ RNA and encodes an essential nucleoporin. We report here the identification of RSS1 (Rat Seven Suppressor) as a high-copy extragenic suppressor of the rat7-1 temperature-sensitive allele. Rss1p encodes a novel essential protein of 538 amino acids, which contains an extended predicted coiled-coil domain and is located both at nuclear pore complexes (NPCs) and in the cytoplasm. RSS1 is the first reported high-copy extragenic suppressor of a mutant nucleoporin. Overexpression of Rss1p partially suppresses the defects in nucleocytoplasmic export of poly(A)+ RNA, rRNA …

Multiple-Trait Gibbs Sampler For Animal Models: Flexible Programs For Bayesian And Likelihood-Based (Co)Variance Component Inference, C. P. Van Tassell, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

A set of FORTRAN programs to implement a multiple-trait Gibbs sampling algorithm for (co)variance component inference in animal models (MTGSAM) was developed. The MTGSAM programs are available to the public. The programs support models with correlated genetic effects and arbitrary numbers of covariates, fixed effects, and independent random effects for each trait. Any combination of missing traits is allowed. The programs were used to estimate variance components for 50 replicates of simulated data. Each replicate consisted of 50 animals of each sex in each of four generations, for 400 animals in each replicate for two traits. For MTGSAM, informative prior …

A Novel Iron-Regulated Metal Transporter From Plants Identified By Functional Expression In Yeast., David Eide, Margaret Broderius, Jeanette Fett, Mary Lou Guerinot

Dartmouth Scholarship

Iron is an essential nutrient for virtually all organisms. The IRT1 (iron-regulated transporter) gene of the plant Arabidopsis thaliana, encoding a probable Fe(II) transporter, was cloned by functional expression in a yeast strain defective for iron uptake. Yeast expressing IRT1 possess a novel Fe(II) uptake activity that is strongly inhibited by Cd. IRT1 is predicted to be an integral membrane protein with a metal-binding domain. Data base comparisons and Southern blot analysis indicated that IRT1 is a member of a gene family in Arabidopsis. Related sequences were also found in the genomes of rice, yeast, nematodes, and humans. In Arabidopsis, …

Postpollination Mechanisms Influencing Mating Patterns And Fecundity: An Example From Eichhornia Paniculata, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Plant mating systems are influenced by the amount and genetic composition of pollen grains deposited on stigmas and by the ability of recipients to discriminate among pollen from different sources. We describe an experimental procedure that uses limiting and excess pollinations with mixtures of genetically marked pollen to partition the siring success of donors into three components: prefertilization gamete attrition (failure of male gametophytes before fertilization), pollen competitive ability (differences in pollen tube growth rate), and postfertilization gamete attrition (embryo abortion). Regression models for the relationships of pollen load size with each pollen's siring success and total recipient fecundity indicate …

Variances Of Additive And Dominance Genetic Effects For Ovulation And Twinning Rates In A Population Selected For Twinning, L. Dale Van Vleck, K. E. Gregory

Department of Animal Science: Faculty Publications

Estimates of variances due to additive and dominance genetic effects and permanent and temporary environmental effects were obtained for ovulation and twinning rates from a composite population selected for twinning rate. Measures of ovulation rate after 11 mo of age on 2,317 heifers with a total of 19,209 measures were used. Twinning measures were on 1,522 first-parity cows, 1,311 later-parity cows with a total of 3,571 measures, and 1,704 all-parity cows with 5,100 measures. Models included fixed effects of year-season-age at calving for twinning, and year-season of birth, age in months, and calendar month of measurement for ovulation rate. Four …

Microevolutionary Patterns And Molecular Markers: The Genetics Of Geographic Variation In Ascaris Suum, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

Molecular markers have been used only rarely to characterize the population genetic structure of nematodes. Published studies have suggested that different taxa may show distinct genetic architectures. Isoenzyme and RAPD markers have been used to investigate geographic variation of Ascaris suum at the level of infrapopulations (nematodes within individual hosts), within localities, and among geographic regions. Independent estimates of genetic differentiation among population samples based on isoenzyme and RAPD data showed similar patterns and substantial correlation. Heterozygote deficiencies within infrapopulations and large values for inbreeding coefficients among infrapopulations suggested that the composition of these populations was not consistent with a …

Mutation Or Deletion Of The Saccharomyces Cerevisiae Rat3/Nup133 Gene Causes Temperature-Dependent Nuclear Accumulation Of Poly(A)+ Rna And Constitutive Clustering Of Nuclear Pore Complexes, Ou Li, Catherine V. Heath, David C. Amberg, Thomas C. Dockendorff, Connie S. Copeland, Michael Snyder, Charles N. Cole

Dartmouth Scholarship

To identify genes whose products play potential roles in the nucleocytoplasmic export of messenger RNA, we isolated temperature-sensitive strains of Saccharomyces cerevisiae and examined them by fluorescent in situ hybridization. With the use of a digoxigen-tagged oligo-(dT)50 probe, we identified those that showed nuclear accumulation of poly(A)+ RNA when cells were shifted to the nonpermissive temperature. We describe here the properties of yeast strains bearing the rat3-1 mutation (RAT-ribonucleic acid trafficking) and the cloning of the RAT3 gene. When cultured at the permissive temperature of 23 degrees C, fewer than 10% of cells carrying the rat3-1 allele showed nuclear accumulation …

Protein-Peptide Interactions Analyzed With The Yeast Two-Hybrid System, Meijia Yang, Zining Wu, Stanley Fields

Dartmouth Scholarship

The yeast two-hybrid system was used to screen a library of random peptides fused to a transcriptional activation domain in order to identify peptides capable of binding to the retinoblastoma protein (Rb). Seven peptides were identified, allof which contain the Leu-X-Cys-X-Glu motif found in Rb-binding proteins, although their activity in the yeast assay variedover a 40-fold range. Mutagenesis of the DNA encoding two of these peptides followed by screening in the two-hybrid systemallowed the delineation of residues apart from the invariant Leu, Cys and Glu that affect binding to Rb. Binding affinities of a peptide and one of its variants …

Assessing Sequential Oncogene Amplification In Human Breast Cancer, Laura E. Janocko, Joseph F. Lucke, David W. Groft, Kathryn A. Brown, Charles A. Smith, Agnese A. Pollice, Sarita G. Singh, Robert Yakulis, Robert J. Hartsock, Stanley E. Shackney

Joseph Lucke

Studies of amplification and/or overexpression of c-myc, HER-2/neu, and H-ras in breast cancer have shown that each is associated with a poor prognosis. The purpose of this study was to explore the possibility that there is a preferred sequence of amplification of these oncogenes in breast cancer. The frequencies of amplification and patterns of co-amplification of c-myc, HER-2/neu, and H-ras were studied in a group of 84 breast cancers. The data suggested a preferred sequence of amplification that consisted of c-myc amplification-HER-2/neu amplification-H-ras amplification. This model was supported by loglinear analysis. In addition, the levels of amplification of JC-A, a …

A Phylogenetic Analysis Of Vertebrate And Invertebrate Notch-Related Genes, Eleanor M. Maine, James L. Lissemore, William T. Starmer

Biology - All Scholarship

Members of the Notch gene family are thought to mediate inductive cell-cell interactions during develop ment of a wide variety of vertebrates and invertebrates. These genes encode transmembrane proteins that appear to act as receptors and contain three repeated sequence motifs. Two of these motifs (an epidermal growth factor like sequence and a cdc10/SW16/ankyrin sequence) have been found in a large number of unrelated proteins, while the third motif (a lin-12/Notch/glp-1 sequence) is unique to proteins of the Notch family. We present a phylogenetic analysis of 17 Notch-related genes from eight species that has implications as to the origins and …

G95-1271 Mastitis Is A Disease -- Control Is An Everyday Task, Gerald R. Bodman, Duane N. Rice

University of Nebraska-Lincoln Extension: Historical Materials

A comprehensive mastitis control program will effectively control infections caused by both environmental and contagious pathogens.

Herd mastitis problems can be caused by both environmental and contagious pathogens (disease-causing organisms). These problems may occur separately or simultaneously. Various testing techniques are necessary to determine the type of causative organism and the infection level of the herd or individual cow. Appropriate tests include the CMT (California Mastitis Test), milk market somatic cell count (SCC), Dairy Herd Improvement Association (DHIA) SCC and laboratory cultures of milk from infected cows. Depending upon test results, mastitis control strategies may need to be changed to …

Carbon Allocation And Partitioning In Aspen Clones Varying In Sensitivity To Tropospheric Ozone, M.D. Coleman, R.E. Dickson, J.G. Isebrands, D.F. Karnosky

Aspen Bibliography

No abstract provided.

Genetics Of The Stable Fly., David B. Taylor

David B. Taylor

No abstract provided.

Circadian Clock Locus Frequency: Protein Encoded By A Single Open Reading Frame Defines Period Length And Temperature Compensation., Benjamin D. Aronson, Keith A. Johnson, Jay C. Dunlap

Dartmouth Scholarship

The frequency (frq) locus encodes a key component, a state variable, in a cellular oscillator generating circadian rhythmicity. Two transcripts have been mapped to this region, and data presented here are consistent with the existence of a third transcript. Analysis of cDNA clones and clock mutants from this region focuses attention on one transcript encoding a protein. FRQ, which is a central clock component: (i) mutations in all of the semidominant frq alleles are the result of single amino acid substitutions and map to the open reading frame (ORF) encoding FRQ; (ii) deletion of this ORF, or a frameshift mutation …

A Thyroid Hormone-Regulated Gene In Xenopus Laevis Encodes A Type Iii Iodothyronine 5-Deiodinase., Donald L. St Germain, Robert Schwartzman, Walburga Croteau, Akira Kanamori, Zhou Wang, Donald D. Brown, Valerie Galton

Dartmouth Scholarship

The type III iodothyronine 5-deiodinase metabolizes thyroxine and 3,5,3'-triiodothyronine to inactive metabolites by catalyzing the removal of iodine from the inner ring. The enzyme is expressed in a tissue-specific pattern during particular stages of development in amphibia, birds, and mammals. Recently, a PCR-based subtractive hybridization technique has been used to isolate cDNAs prepared from Xenopus laevis tadpole tail mRNA that represent genes upregulated by thyroid hormone during metamorphosis. Sequence analysis of one of these cDNAs (XL-15) revealed regions of homology to the mRNA encoding the rat type I (outer ring) 5'-deiodinase, including a conserved UGA codon that encodes selenocysteine in …

Cystic Fibrosis Transmembrane Conductance Regulator Mutations That Disrupt Nucleotide Binding, James Logan, David Hiestand, Paru Daram, Zhen Huang, Donald D. Muccio, John Hartman, Boyd Haley, William J. Cook, Eric J. Sorscher

Molecular and Cellular Biochemistry Faculty Publications

Increasing evidence suggests heterogeneity in the molecular pathogenesis of cystic fibrosis (CF). Mutations such as deletion of phenylalanine at position 508 (delta F508) within the cystic fibrosis transmembrane conductance regulator (CFTR), for example, appear to cause disease by abrogating normal biosynthetic processing, a mechanism which results in retention and degradation of the mutant protein within the endoplasmic reticulum. Other mutations, such as the relatively common glycine-->aspartic acid replacement at CFTR position 551 (G551D) appear to be normally processed, and therefore must cause disease through some other mechanism. Because delta F508 and G551D both occur within a predicted nucleotide binding …

A New Species Of Heterorhabditis From The Hawaiian Islands, Scott Lyell Gardner, S. Patricia Stock, Harry K. Kaya

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

A new species of nematode of the genus Heterorhabditis (Nemata: Heterorhabditidae) was found during a survey of the soil entomopathogenic nematode fauna of the Hawaiian Islands. Heterorhabditis hawaiiensis sp. n. can be separated from all other species of Heterorhabditis by the length of the infective juvenile and the morphological characters of the spicules, gubemaculum, and bursa. Random amplified polymorphic DNA (RAPD) fragment analysis showed that this species also has a distinct genetic pattern in RAPD bands relative to the other 6 species or isolates of Heterorhabditis that were compared.