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Full-Text Articles in Cell Biology

Engineering An Improved Expression Vector For The Nupl53 Rna Binding Domain, Francisca Maertens Apr 2007

Engineering An Improved Expression Vector For The Nupl53 Rna Binding Domain, Francisca Maertens

Life and Environmental Sciences Undergraduate Theses

The nucleoporin Nupl53 has a critical role in both import and export of cellular substances across the nuclear envelope. A unique RNA binding domain has been revealed in Nupl53 (Nupl53-RBD). In order to further understand the interaction between the RNA binding domain (RBD) of Nupl53 and RNA, a crystal structure of the domain would be invaluable. This can be accomplished only if a significant quantity of purified RBD is isolated. Several RBD constructs have been produced to aid in purification of this protein. In most cases, recombinant RBD preparations are fairly heterogeneous and thus unsuitable for structural studies. However, a ...


Developing Proteomics Techniques For Glycosylated Proteins, Adrienne Udelhoven Apr 2006

Developing Proteomics Techniques For Glycosylated Proteins, Adrienne Udelhoven

Life and Environmental Sciences Undergraduate Theses

The ability to study proteins and their role in cell function is a central area of scientific study. To learn more about proteins and glycosylation, a form of posttranslational modification, a means of detecting specifically for glycosylation is necessary. The modification of an existing dye to meet this need was the goal ofthe project. N-benzyl-4-nitroaniline and methyl ((4-(4-nitrophenyl)amino)methyl)benzoate, two intermediate compounds in the synthesis, were created and purified.


The Role Of E2f1 In Endocycle Regulation, Lindsay Black Apr 2004

The Role Of E2f1 In Endocycle Regulation, Lindsay Black

Life and Environmental Sciences Undergraduate Theses

In D. melanogaster, CycE and E2F1 are critical proteins in endocycle control. It is known that both of these proteins are required for endocycling and that cycE mRNA and protein oscillate in endoreduplicating tissues (ERT’s). The mechanism of endocycle regulation by E2F1 through CycE, however, has not been elucidated. Here, I implicate E2F1 protein oscillation in the fluctuation of two of its specific target genes, cycE and rnr2, which is then responsible for the G-S transition ofDrosophila ERT’s. The results also suggest that E2F1 control of S phase initiation within the endocycling cell is dependent on nutritional inputs.


Differential Expression Of Mitochondrial Proteins In Alzheimer’S Disease Patients Compared To Age-Matched Controls, Erin Flaherty Apr 2004

Differential Expression Of Mitochondrial Proteins In Alzheimer’S Disease Patients Compared To Age-Matched Controls, Erin Flaherty

Life and Environmental Sciences Undergraduate Theses

To date, the pathology of Alzheimer’s remains unknown, and many researchers have focused on the mitochondria as playing a significant role in its progression. In earlier studies, it was found that mRNA levels of mitochondrial proteins of Alzheimer’s Disease patients were altered in mouse and human models. Additional research is warranted to determine if the mRNA differences are translated to the protein level. It has been shown that mitochondrial genes are differentially expressed in Alzheimer’s patients when compared to age-matched controls. I propose the levels of the translated gene product will also be altered. To test this ...


The Effect Of Pkc 5 Inhibitors On Pma-Induced Apoptosis In Xenopus Laevis Splenocytes, Annie Crater Apr 2003

The Effect Of Pkc 5 Inhibitors On Pma-Induced Apoptosis In Xenopus Laevis Splenocytes, Annie Crater

Life and Environmental Sciences Undergraduate Theses

Protein kinase C (PKC) controls apoptosis in amphibian systems such as that of the South African clawed frog, Xenopus laevis. The effects of cancer inducing agents like phorbol 12-myristate 13-acetate (PMA) when combined with Ca2+ independent PKC inhibitors on programmed cell death were studied in A laevis splenocytes. Regulation of PMA-activated cells was observed via Annexin V-FITC and propidium iodide assays, flow cytometry, and Western blot analysis. Results indicate the PKC inhibitors reduced both apoptosis and cell growth in PMA-stimulated X. laevis splenocytes compared to PMA alone. These results are valuable to future mammalian cancer research. By identifying the various ...


Analysis Of Candidate Proteins Interacting With Eyal, Ryan Schwanke Apr 2002

Analysis Of Candidate Proteins Interacting With Eyal, Ryan Schwanke

Life and Environmental Sciences Undergraduate Theses

The Eyal gene is important for mammalian organogenesis, and mutations in the human EYA1 results in Branchio-Oto-Renal (BOR) syndrome. This syndrome is autosomal dominant and causes combinations of branchial, otic, and renal anomalies. All Eya gene products contain an extremely conserved 271 amino acid C-terminus that is essential in protein-protein interaction. Recently, it was found that during mouse development, the expression of certain Six genes relied on the function of Eyal, and that Eyal interacts with relevant Six proteins through its C-terminal domain. These results provided insight into the molecular and developmental basis for organ defects occurring in BOR syndrome ...


Acid Phosphatase Content And Acidity Of The Perialgal Vacuole Of Ephydatia Muelleri, Camette Miller Apr 1997

Acid Phosphatase Content And Acidity Of The Perialgal Vacuole Of Ephydatia Muelleri, Camette Miller

Life and Environmental Sciences Undergraduate Theses

Freshwater sponges containing symbiotic algae can serve as a model for the study of relationships in which a host and an intracellular symbiont benefit. In freshwater sponges, symbiotic algae belonging to the genus, Chlorella, are housed in large cytoplasmic vacuoles, called perialgal vacuoles. I used microscopic techniques in an effort to determine whether the perialgal vacuoles ofthe freshwater sponge, Ephydatia muelleri, (1) contain active acid phosphatase, a lysosomal enzyme and (2) are acidic. Whereas the postcoupling method for localizing active acid phosphatase gave equivocal results, the Gomori method for localizing the enzyme revealed that few of the perialgal vacuoles possesed ...


Mitochondrial Dna Of The Thatching Ant, Formica Obscuripes, Gregory Park Apr 1996

Mitochondrial Dna Of The Thatching Ant, Formica Obscuripes, Gregory Park

Life and Environmental Sciences Undergraduate Theses

In a continuing attempt to purify mitochondrial DNA from the thatching ant, modifications were made to a previously developed extraction procedure. Although mitochondria were highly enriched in a subcellular fraction derived from the heads of the ants, when DNA purified from the fraction by an alkaline lysis procedure was electrophoresed, inconsistent results were obtained. Bands in the gel show a molecule larger than 22 kilobase pairs, which is not expected of mtDNA.


A Comparative Study Of The Binding Of Two Lectins In The Early Development Of The Freshwater Sponge, Ephydatia Mulleri, Jay Taylor Apr 1996

A Comparative Study Of The Binding Of Two Lectins In The Early Development Of The Freshwater Sponge, Ephydatia Mulleri, Jay Taylor

Life and Environmental Sciences Undergraduate Theses

Carbohydrates have been implicated in cell adhesion and in developmental processes. Lectin histochemistry using ConcanavalinA and Lotus lectin was used to localize lectin-accessible mannosyl and fucosyl residues in a maturing sponge developing from histoblasts generated during germination of a gemmule. With the exception of cystencytes found in the sponges stained with Lotus lectin, a similar staining pattern was seen with the two lectins, but there was a rather significant difference in the intensity of staining. This difference in staining intensity was thought to be a result of either more mannosyl residues available to the lectin or that the concentration of ...


Preliminary Attempts To Purify Genomic And Mitochondrial Dna From A Freshwater Sponge, Derek Gordon Apr 1996

Preliminary Attempts To Purify Genomic And Mitochondrial Dna From A Freshwater Sponge, Derek Gordon

Life and Environmental Sciences Undergraduate Theses

This project was intended to be a pair of preliminary experiments from which more detailed and specific experiments could be expanded. There were two procedures used in carrying out this study involving the isolation of DNA from a freshwater sponge. First, genomic DNA was isolated and purified. This genomic DNA was digested with the restriction endonuclease EcoR1 and then analyzed using agarose gel electrophoresis. The results showed an accumulation of the sponge DNA in one major band roughly slightly larger than the 21226 bp band generated by EcoR1 digestion of X-phage DNA. The second part of this experiment was an ...


Concanavalin A-Binding Glycoconjugates In The Freshwater Sponge, Ephydatia Mulleri, Marek Janout Apr 1995

Concanavalin A-Binding Glycoconjugates In The Freshwater Sponge, Ephydatia Mulleri, Marek Janout

Life and Environmental Sciences Undergraduate Theses

This preliminary study investigated the distribution and role of cell surface carbohydrates which were suspected to affect proximal cell interactions such as recognition and adhesion. Recognition and adhesion play roles in the development of many organisms but are easily followed in freshwater sponges. The distribution of glycoconjugates in a freshwater sponge Ephydatia mulleri was investigated with the Periodic acid-Schiff (PAS) reaction and lectin histochemistry. PAS revealed the distribution of general carbohydrate in the sponge. Lectin histochemistry used Concanavalin A (ConA), a mannosebinding lectin, coupled through avidin and biotin to horseradish peroxidase enzyme (HRP) to reveal the location of mannose-containing glycoconjugates ...


Immunomagnetic Selection Of Acrosome-Reacted Bovine Spermatozoa, Thomas Mccormick Apr 1993

Immunomagnetic Selection Of Acrosome-Reacted Bovine Spermatozoa, Thomas Mccormick

Life and Environmental Sciences Undergraduate Theses

The anterior end of the mammalian sperm nucleus is covered by a thin, double-layered membranous sac that contains hydrolytic enzymes including acrosin, hyaluronidase, esterases and acid hydrolases. These enzymes, which are involved in the initial phase of fertilization, are activated and released during the acrosome reaction. This exposure of the acrosomal contents occurs not only during fertilization, but also during sperm death.

Acrosome-reacted sperm cells were selected from thawed, cryopreserved samples of bovine spermatozoa using rabbit antibodies to bovine acrosine and goat anti-rabbit immunoglobulin-coated magnetic beads. The selection process was monitored by staining with fluorescence isothiocynate- beads coupled to anti-rabbit ...


The Effect Of Retinoic Acid On Normal Human Foreskin Epithelial Cells And Hpv-Immortalized Cells Grown In Organotypic Raft Cultures, Kristin Whittenburg Apr 1992

The Effect Of Retinoic Acid On Normal Human Foreskin Epithelial Cells And Hpv-Immortalized Cells Grown In Organotypic Raft Cultures, Kristin Whittenburg

Life and Environmental Sciences Undergraduate Theses

Previous studies have shown that epithelial cells immortalized by human papillomaviruses (HPVs) at late passages were more resistant to the effects of retinoic acid than late passage normal keratinocytes. Some of these late passage HPV-immortalized cells, however, lose the ability to form a cornified envelope with continued culturing. For this reason, early passage normal keratinocytes and early passage HPV-immortalized cells were studied to see if they also showed this resistance to retinoic acid. Normal epithelial cells and cells immortalized by HPVs were grown in organotypic raft cultures and treated with varying amounts of retinoic acid, which normally blocks terminal differentiation ...


In Vitro Study Of The Effect Of Hypothermia On The Dissociation Curve Of Blood, Matthew Munding Apr 1992

In Vitro Study Of The Effect Of Hypothermia On The Dissociation Curve Of Blood, Matthew Munding

Life and Environmental Sciences Undergraduate Theses

The aim of this study was to examine the change in the dissociation curve of oxygen from human hemoglobin at the temperatures of 37°, 25°, 18°, 12°, 7°, and 3° C. The partial pressures of oxygen and the calculated hemoglobin saturations were determined for samples at the various temperatures. From this data the partial pressures at 75% saturation were calculated, and the differences in the partial pressures at 75% saturation were compared. The dissociation curve was shown to shift to the left as the temperature was decreased down to 12°. Below 12°, the shift was not further observed. At the ...


Immunohistochemical Labeling Of Vinculin In The Embryonic Chick, Jon Bullman Apr 1991

Immunohistochemical Labeling Of Vinculin In The Embryonic Chick, Jon Bullman

Life and Environmental Sciences Undergraduate Theses

Vinculin is an intracellular protein that links the cytoskeleton with the plasma membrane. It is found in all adhering junctions--both cell-cell and cell-surface. Its location puts it at the center of a fundamental process of embryogenesis--the epithelial-mesenchymal transition. An immunohistochemical labelling technique for the localization of vinculin was developed. This technique could be used in an attempt to understand the fundamental processes of development by applying it to the study of epithelialmesenchymal transitions in the somite of a chick embryo.


Immunohistochemical Localization Of A-Cam In The Embryonic Chick, Larie Smoyer Apr 1991

Immunohistochemical Localization Of A-Cam In The Embryonic Chick, Larie Smoyer

Life and Environmental Sciences Undergraduate Theses

Tissue sections of chick embryos were immunohisto- chemically stained for the presence of A-CAM, a cell surface protein associated with epithelial tissues. This was to determine an effective method of immunohistochemical staining for A-CAM and to study the distribution of A-CAM in the embryonic chick. A method of immunohistochemical staining was developed.


Identification Of Laminin Domains That Promote Tumor Cell Adhesion, Corby Freitag Apr 1991

Identification Of Laminin Domains That Promote Tumor Cell Adhesion, Corby Freitag

Life and Environmental Sciences Undergraduate Theses

The process of metastasis requires tumor cells to migrate through the basement membrane which consists of laminin, a glycoprotein which promotes the adhesion of HT-1080 fibrosarcoma cells. The present study was designed to test four peptides, corresponding to short sequences of the intact laminin molecule, for cell adhesion-promoting activity. By using three different cell migration assays, the four peptides were monitored for their cell adhesive-promoting activity. Results were obtained showing some cell adhesive-promoting activity from all four peptides.


Cellular Changes Occurring During Mesenchymo-Epithelial And Epithelio-Mesenchymal Transitions In The Chick Embryo, Chad Rountree Apr 1990

Cellular Changes Occurring During Mesenchymo-Epithelial And Epithelio-Mesenchymal Transitions In The Chick Embryo, Chad Rountree

Life and Environmental Sciences Undergraduate Theses

Epithelium and mesenchyme are two distinctive cell types. Transitions occur between these during embryonic development of the mammal and chick. The chick embryo was used as a model system to study the cellular and molecular characteristics defining an epithelium and mesenchymal cell. A procedure was established to prepare serial sections of chick embryos for light microscopy observation. A study of this nature may indicate factors involved in bringing about such cellular transitions and contribute to our knowledge of what occurs in disease processes caused by the loss of a cell's typical morphology.


Growth Characteristics Of Large Granular Lymphocytes In Vitro Upon Stimulation With Mitogens Phytohemagglutinin And Recombinant Interleukin-2, Lisa Morin Apr 1988

Growth Characteristics Of Large Granular Lymphocytes In Vitro Upon Stimulation With Mitogens Phytohemagglutinin And Recombinant Interleukin-2, Lisa Morin

Life and Environmental Sciences Undergraduate Theses

A pilot experiment was performed in which peripheral blood lymphocytes were isolated from whole blood using the Ficoll-Hypaque technique. Percoll discontinuous-gradient centrifugation of peripheral blood mononuclear cells resulted in a 2-fold increase in natural killer cell activity coupled with a 3 to 4-fold increase in large granular lymphocytes. Morphology, function (NK activity), and phenotype of Percoll fractions 2-4, presumably large granular lymphocytes, were compared with that of lower density fractions 6-7 over a 28-day period. Augmentation agents phytohemagglutinin and recombinant interleukin-2 were added to the culture medium. Optimal increase in cell number of fractions 2-4 was achieved by the addition ...


Morphological And Cytochemical Characterization Of Rat Adrenocortical Cells In Vitro, Daniel Geehan Apr 1988

Morphological And Cytochemical Characterization Of Rat Adrenocortical Cells In Vitro, Daniel Geehan

Life and Environmental Sciences Undergraduate Theses

Primary monolayer cultures of adrenocortical cells were established from adult female rats of the Wistar strain by single treatment with collagenase type II. This lot of collagenase had been evaluated for collagenase, clostripain, caseinase, and tryptic enzyme activities. The adrenocortical cells were maintained in Dulbecco's Modified Eagle's Medium, Fetal Calf Serum, and gentamycin. Morphological observation of cultures revealed the presence of epithelial cortical cells and absence of medullary cells (epithelial or fibroblastic). The cells contained cytoplasmic lipid granules. In an attempt to localize sites of 3 Beta - hydroxysteroid dehydrogenase activity, cytochemical experiments were performed.


In Situ Hybridization Technique As Applied To Cytogenetics, Daniel Coverdell Apr 1988

In Situ Hybridization Technique As Applied To Cytogenetics, Daniel Coverdell

Life and Environmental Sciences Undergraduate Theses

In our experimentation with the in situ hybridization technique we were unable to band chromosomes with the standard Giemsa staining procedure following autoradiography. Banding was achieved using a replication banding technique in which bromodeoxyuridine (BrdU) was incorporated during replication. The background particles and debris on the chromosomal preparations, which had been in situ hybridized, was reduced by maintaining constant agitation during post-hybridization washes. Excessive background streaks, resulting from cracks in the radiography emulsion, were nearly eliminated by heating the emulsion to 50° C while dipping the slides.


Smooth Muscle Cell Mitogen Production By Endothelial Cells In The Lumens Of Healing Synthetic Vascular Prostheses: A Possible Role In Healing, Gary Reeves Apr 1987

Smooth Muscle Cell Mitogen Production By Endothelial Cells In The Lumens Of Healing Synthetic Vascular Prostheses: A Possible Role In Healing, Gary Reeves

Life and Environmental Sciences Undergraduate Theses

Media was conditioned by culturing endothelial or medial smooth muscle cells in DME-F12 or by time-course perfusions of segments of aorta, synthetic polytetrafluoroethylene (PTFE) arterial grafts with an intact endothelium, and deendothelialized FIFE grafts. These conditioned media samples were used as culture media for quiescent medial smooth muscle cells. Mitogenesis assays were conducted using radioactive thymidine labeling to test each medium for its ability to stimulate the quiescent smooth muscle cells to enter the S phase from the G^Gq phase. Ratios of the thymidine incorporation of cells cultured in conditioned media to those of the negative control, which £ lacked ...


The Study Of The Effects Of 60-Hz Electric Fields On The Cloning Efficiencies Of Chinese Hamster Ovary Cells, Julie Popp Apr 1987

The Study Of The Effects Of 60-Hz Electric Fields On The Cloning Efficiencies Of Chinese Hamster Ovary Cells, Julie Popp

Life and Environmental Sciences Undergraduate Theses

Chinese hamster ovary (CHO) cells were exposed to 60-Hz electric fields at 18 V/m and 5 V/m, and the cloning efficiencies compared. Statistical studies failed to show a significant dose response for the field values tested. However, with regard to the 5 V/m field, a trend of 85% viability compared to sham-exposed cells was discovered. In general, cloning efficiencies for sham-exposed controls were low. Various techniques were employed to increase the efficiencies of the controls. Suggestions for improving controls and the overall procedure are discussed.


Cell Growth Of Saccharomyces Cerevisiae, Miguel Schmitz Apr 1986

Cell Growth Of Saccharomyces Cerevisiae, Miguel Schmitz

Life and Environmental Sciences Undergraduate Theses

From an exponentially growing yeast culture, we obtained a synchronized culture using velocity gradient centrifugation. At five minute intervals, we determined the average cell buoyant density and the peak frequency cell volume to calculate the average cell mass at each of these time intervals. We found that the average yeast cell increases in mass at an exponential rate.


The Use Of Pap To Demonstrate The S100 Antigen In Neoplastic Spleens From Beagle Dogs That Have Been Exposed To Terminated Protracted Whole-Body Gamma Irradiation, Michael Gallagher Apr 1986

The Use Of Pap To Demonstrate The S100 Antigen In Neoplastic Spleens From Beagle Dogs That Have Been Exposed To Terminated Protracted Whole-Body Gamma Irradiation, Michael Gallagher

Life and Environmental Sciences Undergraduate Theses

Thirteen sections of primary splenic sarcomas manifested by eight beagle dogs exposed to protracted ^°Co gamma irradiation were characterized by the use of staining methods. Gomori’s Reticulum stain, Masson’s Trichrorae stain, and PAP (peroxidase-antiperoxidase), an immunohistochemical staining method specific for localization of the S100 antigen, were employed in an attempt to reconcile and unify conflicting histological and ultrastructural evaluations of these tumors. The S100 antigen is thought to be indicative of a neurogenic cytogenealogy. All three staining methods were utilized because of their inclusion in a protocol developed to arrive at a differential diagnosis concerning these primary soft ...


In Vitro Expression Of Radiation-Induced Stem Cell Damage In Macrophage Differentiation, Robert Shillingstad Apr 1986

In Vitro Expression Of Radiation-Induced Stem Cell Damage In Macrophage Differentiation, Robert Shillingstad

Life and Environmental Sciences Undergraduate Theses

An in vitro assay using murine bone marrow cells was used to determine radiation-induced stem cell damage on subsequent in vitro macrophage differentiation. The assay system consisted of cultures of macrophage progenitor cells stimulated by the addition of L-cell conditioned medium high in CSF-1. Experimental animals were exposed to 400 rads of radiation using a Cobalt-60 source. It was found that residual stem cell damage was exhibited in vitro with a reduction of up to 63.9% on day-1 after exposure in the number of macrophage colonies arising in vitro. Proliferative compensation yielded slightly above normal levels of CFU-m by ...


Isolation Of Horse Large Granular Lymphocytes By Density Centrifugation Techniques, And Responsiveness To Human Interleukin-2, Susan Macneill Apr 1985

Isolation Of Horse Large Granular Lymphocytes By Density Centrifugation Techniques, And Responsiveness To Human Interleukin-2, Susan Macneill

Life and Environmental Sciences Undergraduate Theses

The methods of isolating human and rat large granular lymphocytes were reviewed, and revised to accommodate horse lymphocytes. Purified populations of large granular lymphocytes were then stimulated with Interleukin-2 and Concanavalin-A, to observe effects on proliferation and cytotoxic activity. The results of this study suggest that large granular lymphocytes can be purified from the peripheral blood of horses, using a percoll density gradient. Also, Interleukin-2 is shown to have an effect on proliferation of enriched populations of large granular lymphocytes, especially when added in adjunct to Concanavalin-A.


Hemoglobin Synthesis In Mice Doubly Heterozygous For Alpha And Beta Thalassemia, Eric Smith Apr 1984

Hemoglobin Synthesis In Mice Doubly Heterozygous For Alpha And Beta Thalassemia, Eric Smith

Life and Environmental Sciences Undergraduate Theses

The extent of imbalance between the synthesis rate of «-globin polypeptide chains relative to B-globin chains in thalassemic mice is one of the major factors in determining the pathophysiology of thalassemia. Mice doubly heterozygous for both a mutant ®<-thalassemic chromosome and a /?-thalassemic chromosome exhibited a hypochromic, microcytic anemia with mild reticulocytosis and erythrocytosis. However, the erythrocytes of these mice displayed few signs of hemolysis, or poikilocytosis, and did not contain visible inclusion bodies. Analysis of the relative rates of globin chain syntheses in vitro by ^H-leucine incorporation revealed the


A Study Of The Binding Of Rna Polymerase Ii To Mononucleosomes, Sean Russell Apr 1984

A Study Of The Binding Of Rna Polymerase Ii To Mononucleosomes, Sean Russell

Life and Environmental Sciences Undergraduate Theses

In order to arrive at a basic understanding of the mechanism of gene expression in eukaryotic cells, one must first understand the structure and interaction of their components: the structure and conformation of DNA in active and inactive genes, the modification of histones, and the interaction of factors during transcription. Increased research has resulted in several important observations, such as that of the subunit of chromatin structure.^ Further research is underway to determine if this subunit of structure is the actual conformation of DNA in active genes, 2 and how it might be affected by histone modification. Ongoing efforts have ...


The Use Of Envelope Specific Monoclonal Antibodies To Search For Differentiation Antigens Encoded By Endogenous Retroviral Sequences In Murine Hematopoietic Cells, David Olson Apr 1984

The Use Of Envelope Specific Monoclonal Antibodies To Search For Differentiation Antigens Encoded By Endogenous Retroviral Sequences In Murine Hematopoietic Cells, David Olson

Life and Environmental Sciences Undergraduate Theses

Hematopoietic cells in the mouse were examined to detect retrovirus encoded differentiation antigens on their cell surfaces. Twenty-four established lymphoid, erythroid, and myeloid cell lines were studied. A panel of well defined envelope specific monoclonal antibodies were tested against 125 each cell line in a I-protein A cell binding radioimmunoassay to detect retroviral envelope antigens on the cell's plasma membrane. Results were analyzed to discern cell line specific expression of antigens as a basis for the search for differentiation antigens. A few cell lines were selected for further study. Two erythroid cell lines, 7727 and 7883, for example, were ...