Cell and Developmental Biology Commons^™

External Morphology Of The Chorion Of The Annual Fishes Cynolebias (Cyprinodontiformes: Rivulidae), Marcelo Loureiro, Rafael O. De Sá

Biology Faculty Publications

Members of the family Rivulidae (killifishes) inhabit temporary bodies of freshwater in South and Central America (one species is also found in North America). The most remarkable characteristic of the family Rivulidae is that species have an annual life cycle with a drought-resistant egg during the dry season. Parenti's (1981) analysis of the order Cyprinodontiformes considered a single genus, Cynolebias, whereas Cos- ta's (1990) phylogenetic analysis of the family Rivulidae separates Cynolebias from Cynopoecilus. One of Costa's synapomorphies to separate Cynopoecilus is the unique structure of their egg's chorion, which is shared with Leptolebias and Campellolebias.

Numa Assembles Into An Extensive Filamentous Structure When Expressed In The Cell Cytoplasm, Alejandro Saredi, Louisa Howard, Duane A. Compton

Dartmouth Scholarship

NuMA is a 236 kDa protein that participates in the organization of the mitotic spindle despite its strict localization in the nucleus during interphase. To test how cells progress through mitosis when NuMA is localized in the cytoplasm instead of the nucleus, we have deleted the nuclear localization sequence of NuMA using site-directed mutagenesis and transiently expressed this mutant protein (NuMA-DeltaNLS) in BHK-21 cells. During interphase, NuMA-DeltaNLS accumulates in the cytoplasm as a large mass approximately the same size as the cell nucleus. When cells enter mitosis, NuMA-DeltaNLS associates normally with the mitotic spindle without causing any apparent deleterious effects …

The Epidermis Still In Control?, Winfried Peters, A. Tomos

Winfried S. Peters

Reversal Of Cell Fate Determination In Caenorhabditis Elegans Vulval Development, Susan Euling, Victor Ambros

Victor R. Ambros

In Caenorhabditis elegans, the fates of the multipotent vulval precursor cells (VPCs) are specified by intercellular signals. The VPCs divide in the third larval stage (L3) of the wild type, producing progeny of determined cell types. In lin-28 mutants, vulva development is similar to wild-type vulva development except that it occurs precociously, in the second larval stage (L2). Consequently, when lin-28 hermaphrodites temporarily arrest development at the end of L2 in the dauer larva stage, they have partially developed vulvae consisting of VPC progeny. During post-dauer development, these otherwise determined VPC progeny become reprogrammed back to the multipotent, signal-sensitive state …

The History Of Tissue Tension, Winfried S. Peters, A. Deri Tomos

Winfried S. Peters

The Effects Of Prophylatic Protocols Of Exercise And Tamoxifen On The Induction And Growth Of Estrogen Dependent And Independent Rat Mammary Tumors, Robert H. Doepke Jr.

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Robert H. Doepke, Jr. on May 6,1996.

Reversal Of Cell Fate Determination In Caenorhabditis Elegans Vulval Development, Susan Euling, Victor Ambros

Dartmouth Scholarship

In Caenorhabditis elegans, the fates of the multipotent vulval precursor cells (VPCs) are specified by intercellular signals, The VPCs divide in the third larval stage (L3) of the wild type, producing progeny of determined cell types, In lin-28 mutants, vulva development is similar to wild-type vulva development except that it occurs precociously, in the second larval stage (L2), Consequently, when lin-28 hermaphrodites temporarily arrest development at the end of L2 in the dauer larva stage, these otherwise determined VPC progeny become reprogrammed back to the multipotent, signal- sensitive state of VPCs. Our results indicate that VPC fate determination by intercellular …

The Evaluation Of Succinylcholine Chloride For Harmful Effects Upon Early-Stage Mouse Embryos, Francis Warren Prescott

Biological Sciences Theses & Dissertations

Succinylcholine (SCh) chloride is a depolarizing neuromuscular blocking agent used to paralyze patients for surgical procedures. Over 1,800 clinical observations of newborn infants have demonstrated that succinylcholine does not cross the placenta in quantities detrimental to fetuses (Kolstad, et al., 1957, Bakhoum, et al., 1957, Hodges, et al., 1959, Duffield, et al., 1958, Dennis, et al., 1954, 1956, McNab, 1955, Coleman, et al., 1956, Lund, 1953). Later investigations which involved comparison of blood levels of SCh in the mother to those in fetuses bolstered the finding that SCh fails to cross the placenta in significant amounts (Moya and Kvisselgaard, 1961, …

Heterochronic Genes Control Cell Cycle Progress And Developmental Competence Of C. Elegans Vulva Precursor Cells, Susan Euling, Victor Ambros

Victor R. Ambros

Heterochronic genes control the timing of vulval development in the C. elegans hermaphrodite. lin-14 or lin-28 loss-of-function mutations cause the vulval precursor cells (VPCs) to enter S phase and to divide one larval stage earlier than in the wild type. A precocious vulva is formed by essentially normal cell lineage patterns, governed by the same intercellular signals as in the wild type. Mutations that prevent the normal developmental down-regulation of lin-14, activity delay or block VPC division and prevent vulval differentiation. A genetic pathway that includes lin-4, lin-14, and lin-28 controls when VPCs complete G1 and also controls when VPCs …

Bovine Cell Line Resistant To In Vtro Infection By Bovine Viral Darrheavirus And All Other Known Pestiviruses, Ruben O. Donis, Eduardo F. Flores

School of Veterinary and Biomedical Sciences: Faculty Publications

Bovine cell line resistant to infection by the pestiviruses Bovine Viral Diarrhea Virus (BVDV), Hog Cholera Virus (HCV) and Border Disease Virus (BDV) and all progeny and mutants thereof. A bovine cell line (CRIB) that is resistant to infection by cytopathic and non-cytopathic BVDV and by other Pestiviruses due to a stable, recessive genetic defect which blocks infection at the level of viral entry.

Heat Shock Factor Gains Access To The Yeast Hsc82 Promoter Independently Of Other Sequence-Specific Factors And Antagonizes Nucleosomal Repression Of Basal And Induced Transcription, Alexander M. Erkine, C. C. Adams, T. Diken, D. S. Gross

Scholarship and Professional Work – COPHS

Transcription in eukaryotic cells occurs in the context of chromatin. Binding of sequence-specific regulatory factors must contend with the presence of nucleosomes for establishment of a committed preinitiation complex. Here we demonstrate that the high-affinity binding site for heat shock transcription factor (HSF) is occupied independently of other cis-regulatory elements and is critically required for preventing nucleosomal assembly over the yeast HSC82 core promoter under both noninducing (basal) and inducing conditions. Chromosomal mutation of this sequence, termed HSE1, erases the HSF footprint and abolishes both transcription and in vivo occupancy of the TATA box. Moreover, it dramatically reduces promoter chromatin …

Topographically Specific Effects Of Elf-1 On Retinal Axon Guidance In Vitro And Retinal Axon Mapping In Vivo, Masaru Nakamoto

Biology Faculty Publications

Topographic maps, which maintain the spatial order of neurons in the order of their axonal connections, are found throughout the nervous system. In the visual retinotectal projection, ELF-1, a ligand in the tectum, and its receptors in the retina show complementary gradients in expression and binding, indicating they may be positional labels for map development. Here we show that ELF-1 acts as a repellent axon guidance factor in vitro. In vivo, when the tectal ELF-1 pattern is modified by retroviral overexpression, retinal axons avoid ectopic ELF-1 patches and map to abnormally anterior positions. All these effects were seen on axons …

Modulated Structures In Electrodeposited Superconducting Ba(1-X)K(X)Bio(3), Chad Bryant Huffman

Theses, Dissertations and Capstones

Compositionally modulated crystals of the superconductor Ba_1-x K_xBiO₃ have been grown electrochemically. Modulation was produced through control of the deposition potential.

Modulated crystals were imaged using optical microscopy, backscattered SEM, and STM. The expected linear relationship between the amount of time that current was applied and the modulation thickness was observed, and the growth rates were determined.

Multilayers were differentially etched using an EDTA solution. Etched and unetched samples were imaged using backscattered SEM.

The transition temperature of a modulated sample was determined by SQUID magnetometry to equal the bulk value.

Use Of The (3)H-Tetracycline Rat Model In The Study Of Skeletal Compartmentalization And Metabolism Of Calcium In The Maturing Male And Female Rat And The Role Of The Skeleton In Calcium Homeostasis In The Adolescent Male Rat, Darrin Lee Demoss

Theses, Dissertations and Capstones

The (3)H-tetracycline bone labeling procedure was employed to monitor bone resorption from urinary loss curves in male and female rats of various ages. In addition, whole body dry skeletal mass and the loss of (3)H-tetracycline from individual bones was determined. It was found that the dry skeletal mass/body mass ratio of 24-week-old females was 30-40% greater than that for males. The urinary loss of (3)H-tetracycline was described by a double exponential equation indicating the presence of two distinct and independent exchangeable bone compartments. Both compartments decrease in size with age, but their label loss activities were different. The label loss …

Regulation Of Melanogenesis In B16 Mouse Melanoma Cells By Protein Kinase C (Pkc), Harish Mahalingam

Theses, Dissertations and Capstones

The pigment cell-specific expression of tyrosinase and TRP1 has been shown to be important for the production of melanin in pigmented cells. Using a pigmented cell line, B16 mouse melanoma, we obtained evidence that PKC plays a major role in regulating melanogenesis. Chronic treatment with phorbol dibutyrate (PDBu) leads to downregulation of PKC activity and protein levels. This is accompanied by a loss of pigmentation which is correlated with a 50% reduction and a complete loss of TRP1 and tyrosinase respectively. Similar results were obtained with Northern and Western blotting indicating that PKC may regulate the steady state levels of …

Postnatal Development Of The Neural Retina In A South American Opossum: Monodelphis Domestica, Tracy L. Soltesz

Theses, Dissertations and Capstones

Postnatal retinal development was studied in a marsupial opossum, Monodelphis domestica using light microscopy and 3H-thymidine autoradiography. For the light microscopic study, opossum neonates at 1, 3, 7, 14, 21, 25 and 28 days of age were euthanized, fixed and processed into paraffin sections for hematoxylin and eosin staining. The distinct ganglion cell layer, first observed on postnatal day (P) 7, was separated from the outer neuroblasts by the inner plexiform layer. The neuroblast layer was divided into inner and outer nuclear layers on P25 by the presumptive outer plexiform layer, indicated by discrete intercellular spaces located between the nuclear …

Genetic Analysis Of Rhinichthys Atratulus (Pisces: Cyprinidae) In North Central West Virginia, Alan Harper Tennant

Theses, Dissertations and Capstones

The blacknose dace, Rhinichthys atratulus, is a cyprinid minnow common to shallow streams throughout North America. It has been shown to be sensitive to anthropogenic stress and a study of the genetic nature of R. atratulus populations may yield information about their habitats. In West Virginia, two subspecies of R. atratulus are present, R. a. atratulus and R. a. obtusus, which are separated by the Allegheny divide. In north central West Virginia, R. a. atratulus was observed in the Cheat River drainage, an area previously thought be within the range of R. a. obtusus. Fish of the R. a. atratulus …

Características De La Osificación Craneal En Phyllomedusa Boliviana (Anura: Hylidae), Rafael O. De Sá, E. O. Lavilla

Biology Faculty Publications

RESUMEN. Dentro de la familia Hylidae disponemos de información sobre las secuencias de osificación craneal para menos del 4.0% de sus miembros. El presente trabajo describe la secuencia de osificación craneal de Phyllomedusa boliviana. El patrón general de osificación es similar a lo reportado para otras especies de la familia, pero existen algunas diferencias importantes tales como la osificación tardía de los próoticos y la osificación premetamórfica de neopalatino, vómer, cuadrado-yugal, pterigoides y columela. El lento desarrollo ulterior de la osificación resulta en juveniles con cráneos extensamente cartilaginosos.

ABSTRACT. Characteristics of the cranial ossification in Phyllomedusa …

Phylogeny Of The Haplosporidia (Eukaryota: Alveolata) Based On Small Subunit Ribosomal Rna Gene Sequence, Brenda Sandy Flores

Dissertations, Theses, and Masters Projects

No abstract provided.

The Development Of Affinity Maturation In Rainbow Trout Oncorhynchus Mykiss, Ing Wei Khor

Dissertations, Theses, and Masters Projects

No abstract provided.

Examination Of The Cell Wall Of Micrasterias Radiosa Var Radiosa (Conjugatophyceae) By Transmission And Scanning Electron Microscopy, Jennifer A. Akin, Richard L. Meyer

Journal of the Arkansas Academy of Science

The cell wall of Micrasterias radiosa var. radiosa Ralfs 1848 (Conjugatophyceae) was examined by transmission and scanning electron microscopy. Previous electron microscopy of this taxon has not been performed; thus these are new observations. The cell wall was recognized to be of the Cosmarium type with complex pores external to the plasma membrane that penetrate the secondary wall and with ornamentation arising from the secondary wall. Subdivided regions of the pore apparatus, the pore head, pore bulb, connecting pore channel, and pore depression were detected. Pores of type 4 were located in the isthmal region and at the division of …

Development And Lipid Composition Of The Harpacticoid Copepod Nitocra Spinipes Reared On Different Diets, Gregory M. Weiss, George B. Mcmanus, H. Rodger Harvey

OES Faculty Publications

We reared the harpacticoid copepod Nitocra spinipes on diets of bacteria, a diatom, or a macroalga, evaluating survivorship and growth in short-term (≤ 1 generation) experiments. Lipid content of the copepods and their diets was measured and used as an index of nutrition. Although growth, survivorship and lipid content of N. spinipes were significantly greater when fed the diatom, which had the highest lipid content of the 3 diets, the copepod was able to develop from egg to adult when fed a lipid- poor bacterial diet. Furthermore, this species was able to go through developmental molts without the addition of …

Modulation Of Queuine Uptake And Incorporation Into Trna By Protein Kinase C And Protein Phosphatase, Rana C. Morris, Bonnie J. Brooks, K. Lenore Hart, Mark S. Elliot

Chemistry & Biochemistry Faculty Publications

It has been suggested that the rate of queuine uptake into cultured human fibroblasts is controlled by phosphorylation levels within the cell. We show that the uptake of queuine is stimulated by activators of protein kinase C (PKC) and inhibitors of protein phosphatase; while inhibitors of PKC, and down-regulation of PKC by chronic exposure to phorbol esters inhibit the uptake of queuine into cultured human fibroblasts. Activators of cAMP- and cGMP-dependent kinases exert no effect on the uptake of queuine into fibroblast cell cultures. These studies suggest that PKC directly supports the activity of the queuine uptake mechanism, and that …