Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 60

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Functional Analysis Of The C-Terminal Domain In The Drosophila Jil-1 Histone H3 Kinase, Xiaomin Bao Jan 2008

Functional Analysis Of The C-Terminal Domain In The Drosophila Jil-1 Histone H3 Kinase, Xiaomin Bao

Retrospective Theses and Dissertations

Epigenetic regulation is an important process utilized by biological systems to control gene expression and organize development, with histone modification enzymes among the most important components in this regulatory network. The predominant interphase H3 Serine10 kinase in Drosophila is JIL-1, which plays an important role in regulating chromosome structure and modulating gene expression. The full-length JIL-1 protein is composed of four domains including a N-terminal domain (NTD), two kinase domains (KDI and KDII), and a unique C-terminal domain (CTD). In order to study the biological importance of these individual domains, a domain analysis research approach was taken and different functions ...


Dissection Of The Mitotic And Nuclear Functions Of Chromator, A Nuclear-Derived Spindle Matrix Component In Drosophila, Yun Ding Jan 2008

Dissection Of The Mitotic And Nuclear Functions Of Chromator, A Nuclear-Derived Spindle Matrix Component In Drosophila, Yun Ding

Retrospective Theses and Dissertations

A spindle matrix has long been proposed to serve as a stationary or elastic molecular matrix substrate for the organization and activities of microtubules and motors, based on the consideration of a mechanical and functional support for the stabilization of microtubule spindle during force generation from mitotic motors. Recently, the identification of four Drosophila proteins, Skeletor, Megator, EAST and Chromator has provided molecular evidence for the existence of this macromolecular matrix structure during mitosis. All of these four proteins have been shown to interact with each other within a protein complex and redistribute from the nucleus at interphase to form ...


Role Of Leu[Superscript B 10] In Cytoglobin And Comparison Of Direct And Indirect Measurements Of Hexacoordinate Hemoglobin Ligand Affinity, Jordan Richard Witmer Jan 2007

Role Of Leu[Superscript B 10] In Cytoglobin And Comparison Of Direct And Indirect Measurements Of Hexacoordinate Hemoglobin Ligand Affinity, Jordan Richard Witmer

Retrospective Theses and Dissertations

Hexacoordinate hemoglobins (HxHbs) have recently been discovered and have been found in nearly all living organisms. In humans, hxHbs are represented by neuroglobin (Ngb) and cytoglobin (Cgb). While Ngb is principally found in the brain, Cgb is ubiquitously expressed in all tissues. Ligand binding in hexacoordinate hemoglobins is complex due to the reversible coordination of the heme iron by the distal histidine. Hexacoordination regulates ligand binding and is regulated by specific residues in the heme pocket including the B10 position. Therefore, we investigated the influence of LeuB10 on hexacoordination and ligand binding in Cgb. Ligand binding was analyzed for recombinant ...


Characterization Of Three Spindle Matrix Proteins, Megator, East And Asator, In Drosophila, Hongying Qi Jan 2007

Characterization Of Three Spindle Matrix Proteins, Megator, East And Asator, In Drosophila, Hongying Qi

Retrospective Theses and Dissertations

Two previously identified proteins Skeletor and Chromator provide the molecular evidence for the existence of a spindle matrix complex in Drosophila. The spindle matrix has been proposed to be a macromolecular complex, which plays a role in organization and stabilization of the mitotic spindle as well as in providing structural support for counterbalancing force production.;In this dissertation, I present the identification and characterization of three more putative spindle matrix candidate proteins, Megator, EAST and Asator. Megator, an ortholog of the mammalian TPR protein, contains a large coiled-coil domain at its NH2-terminus and an acidic, non-structural COOH-terminus. Immunohistochemistry studies show ...


Map Based Candidate Gene Cloning And Functional Analysis Of Genes Involved In Vlcfas Synthesis, Li Fan Jan 2007

Map Based Candidate Gene Cloning And Functional Analysis Of Genes Involved In Vlcfas Synthesis, Li Fan

Retrospective Theses and Dissertations

VLCFAs are biosynthesized by an endoplasmic reticulum associated enzyme system, referred to as fatty acid elongase. Fatty acid elongase generates VLCFAs by elongating 18C fatty acids. The enzymatic machinery of fatty acid elongation is believed to be composed of 3-ketoacyl-CoA synthase, 3-ketoacyl-CoA reductase, 3-hydroxyacyl-CoA dehydratase, and enoyl-CoA reductase. However, the insoluble nature of the fatty acid elongase system has hampered efforts to purify the system and to identify the genes that encode the component proteins. In the current study a candidate gene cloning approach was used to demonstrate that the previously defined gl26 gene of maize encodes a predicted enoyl-CoA ...


Analysis Of A Nuclear Complex Of Proteins That Form A Spindle Matrix During Mitosis In Drosophila , Uttama Rath Jan 2005

Analysis Of A Nuclear Complex Of Proteins That Form A Spindle Matrix During Mitosis In Drosophila , Uttama Rath

Retrospective Theses and Dissertations

A spindle matrix is a macromolecular structure hypothesized to provide a stationary support or strut for the anchorage of motor proteins during force generation, microtubule sliding, and chromosome segregation in mitosis. Previous work in Drosophila has shown Skeletor, as the first putative molecular candidate of spindle matrix structure since it possesses many features consistent with the proposed spindle matrix structure.;We have identified two more putative spindle matrix candidate proteins, Chromator and Megator, using yeast two-hybrid interaction assay, cross-immunoprecipitation and immunocytochemistry. Chromator is a novel and essential chromodomain containing protein that interacts directly with Skeletor and extensively colocalizes with it ...


Identification Of A Role For Janus Kinase2 (Jak2) In Skeletal Muscle Mitogenesis, Myogenesis, And Hypertrophy , Symantha Ann Anderson Jan 2005

Identification Of A Role For Janus Kinase2 (Jak2) In Skeletal Muscle Mitogenesis, Myogenesis, And Hypertrophy , Symantha Ann Anderson

Retrospective Theses and Dissertations

Skeletal muscle is a dynamic tissue with tight developmental control and the ability to significantly remodel in the postnatal animal. Understanding the molecular mechanisms underlying skeletal muscle development and postnatal growth is critical to potential therapeutic manipulation. Janus kinase2 (JAK2) is a tyrosine kinase critical for growth of numerous cell types and is causative in many cancers, including leukemia. In this study we sought to understand the role of the JAK/STAT signaling cascade in skeletal muscle. In particular, this research focused on the role of JAK2 in skeletal muscle mitogenesis, myogenesis, and hypertrophy. Little work has been done regarding ...


Structural And Molecular Analysis Of Leech Neuronal Proteins, Calsensin And Filamin , Deepa V. Venkitaramani Jan 2004

Structural And Molecular Analysis Of Leech Neuronal Proteins, Calsensin And Filamin , Deepa V. Venkitaramani

Retrospective Theses and Dissertations

This thesis describes the structural and molecular analysis of two leech neuronal proteins, Calsensin and Filamin. Calsensin is an EF-hand calcium-binding protein expressed by a subset of peripheral sensory neurons which fasciculate into a single tract in the leech central nervous system. Calsensin is a 9 kD protein with two EF-hand calcium-binding motifs. Calsensin can multimerize via disulfide bridge formation involving the two cysteine residues in vitro. Furthermore, Calsensin shows differential gel migration depending on the presence or absence of calcium suggesting a conformational change upon calcium binding. Using multidimensional NMR spectroscopy we have determined the solution structure and backbone ...


The Essential Jil-1 Kinase Regulates Histone H3 Phosphorylation And Maintains Chromatin Structure In Drosophila , Weiguo Zhang Jan 2004

The Essential Jil-1 Kinase Regulates Histone H3 Phosphorylation And Maintains Chromatin Structure In Drosophila , Weiguo Zhang

Retrospective Theses and Dissertations

JIL-1 encodes a chromatin-associated tandem serine/threonine kinase in Drosophila melanogaster. JIL-1 predominantly associates with interbands on polytene chromosomes. It appears at higher levels on the X chromosome than on autosomes in males, and distributes about equally on all chromosomes in females. In addition, in males JIL-1 overlaps with the MSL (for male specific lethal) complex that specifically associates with the male X chromosome on which expression of most genes are upregulated.;We isolated JIL-1 mutants by inducing imprecise excision of an EP element inserted in JIL-1. We found that JIL-1 is required for viability of both females and males ...


Characterization Of Two Novel Spindle Matrix Proteins In Drosophila, Chromator And Megator , Dong Wang Jan 2003

Characterization Of Two Novel Spindle Matrix Proteins In Drosophila, Chromator And Megator , Dong Wang

Retrospective Theses and Dissertations

A spindle matrix has been proposed to help organize and stabilize microtubules during mitosis. This concept has gained new interest due to the identification of Skeletor as a potential component of the spindle matrix. Skeletor is associated with chromosomes during interphase but reorganizes into a spindle-like structure during early prophase before the nuclear envelope breaks down and microtubules enter the nucleus. The Skeletor spindle extends from pole to pole during metaphase coaligning with the microtubule spindle and persists even after nocodazole treatment dissembles the microtubules. These features make Skeletor an ideal candidate as a spindle matrix protein.;In this study ...


Molecular Interactions Of Talin And Actin: A Study On The Specific Domains Of Talin Involved In The Interactions , Ho-Sup Lee Jan 2002

Molecular Interactions Of Talin And Actin: A Study On The Specific Domains Of Talin Involved In The Interactions , Ho-Sup Lee

Retrospective Theses and Dissertations

Talin is an essential cytoskeletal protein present in cell-matrix type adherens junctions where it helps in attachment of the actin cytoskeleton to the plasma membrane. The nature of the interaction between talin and actin was examined in this dissertation by investigating three actin binding sites (ABS1--3), with ABS1 located in the 47 kDa N-terminal head and ABS2 and ABS3 present in the 190 kDa C-terminal tail of the talin molecule. Cosedimentation of expressed GST-fusion deletion constructs from the talin head with F-actin showed that actin binding activity of the talin head is contained within residues 271--320. Talin constructs containing the ...


Mechanisms Of Somatostatin-Induced Paradoxical Increase In Insulin Secretion In The Presence Of Arginine Vasopressin In Clonal [Beta]-Cell Hit-T15 , Henrique Cheng Jan 2002

Mechanisms Of Somatostatin-Induced Paradoxical Increase In Insulin Secretion In The Presence Of Arginine Vasopressin In Clonal [Beta]-Cell Hit-T15 , Henrique Cheng

Retrospective Theses and Dissertations

We investigated the mechanism underlying somatostatin-induced increase in [Ca2+]i leading to insulin release in the presence of arginine vasopressin (AVP) in clonal beta-cell HIT-T15. Somatostatin increased [Ca2+]i and insulin release in a biphasic pattern, characterized by a sharp and transient increase followed by a rapid decline to the sub-basal level. Pretreatment with pertussis toxin, which inactivates Gi/Go, abolished the effects of somatostatin. U-73122, an inhibitor of phospholipase C, antagonized somatostatin-induced increase in [Ca2+] i. In Ca2+-free environment, somatostatin still increased [Ca2+]i, whereas depletion of intracellular Ca 2+ stores with thapsigargin, a microsomal Ca2+ ATPase inhibitor ...


Investigation Of The Effect Of Bcl-2 On Hybridoma Cell Survival , Mark Christopher Mowry Jan 2001

Investigation Of The Effect Of Bcl-2 On Hybridoma Cell Survival , Mark Christopher Mowry

Retrospective Theses and Dissertations

Hybridoma cells are widely used to produce large quantities of monoclonal antibodies for use as medicines and diagnostics. Bcl-2 is an oncogene that has been shown to have an anti-apoptotic effect in many cell lines including hybridomas. This study investigates the effect of various levels of bcl-2 expression on hybridoma cell grown and antibody productivity in both batch and perfusion culture.;H166 hybridomas were transfected with a plasmid containing a bcl-2 insert and stable clones were selected. The cells were grown in spinner flasks in batch mode for twelve days and it was confirmed that expression at high levels allow ...


Coordination Of Cell Morphology And Nuclear Division By The Bud Neck Control Ring In Saccharomyces Cerevisiae , Courtney Lynn Thomas Jan 2001

Coordination Of Cell Morphology And Nuclear Division By The Bud Neck Control Ring In Saccharomyces Cerevisiae , Courtney Lynn Thomas

Retrospective Theses and Dissertations

Coordination of daughter cell growth and nuclear division are readily observed but not well understood in the yeast Saccharomyces cerevisiae . A screen was performed to identify mutants which lost this coordination such that they exhibited an elongated cell morphology (improper cell growth), but continued to divide. The results of this screen and suppressor analysis suggests the bud neck ring is a control structure which determines cell morphology as well as nuclear division as an upstream regulator of Cdc28p-cyclin complexes.;The effects of mutations in specific components of the bud neck ring on the assembly of other components into the structure ...


Drosophila Jil-1 Kinase Mediates Histone H3 Ser10 Phosphorylation, Maintains Higher Order Chromatin Structure, And Is Implicated In Dosage Compensation , Yanming Wang Jan 2001

Drosophila Jil-1 Kinase Mediates Histone H3 Ser10 Phosphorylation, Maintains Higher Order Chromatin Structure, And Is Implicated In Dosage Compensation , Yanming Wang

Retrospective Theses and Dissertations

The Drosophila JIL-1 tandem Ser/Thr kinase is associated with chromosomes/chromatin throughout the cell cycle in early embryos and localized to hundreds of sites on the open interband regions on third instar larvae polytene chromosomes. Interestingly, the level of JIL-1 is upregulated on the male X chromosome, which is hypertranscribed for dosage compensation. The distribution of JIL-1 overlaps with that of MSL (male specific lethal) proteins and JIL-1 is associated with the MSL complex.;To further study the function of JIL-1 in vivo, a series of JIL-1 mutants from hypomorphs to null were generated. Analyzing the phenotypes of JIL-1 ...


Mechanisms Of Negative Regulation Of Protein Prenylation: Investigation Of Murine Guanylate-Binding Protein 1 , John Thomas Stickney Jan 2000

Mechanisms Of Negative Regulation Of Protein Prenylation: Investigation Of Murine Guanylate-Binding Protein 1 , John Thomas Stickney

Retrospective Theses and Dissertations

Covalent attachment of isoprenoid lipids to proteins is a post-translational modification that occurs on approximately 2% of all cellular proteins. Proteins that contain a CaaX motif as their final four amino acids are presumed to be targets for the addition of C15 or C20 isoprenoids by farnesyl transferase (FTase) or geranylgeranyl transferase I (GGTase I) respectively. This modification is generally believed to occur stoichiometrically, and irreversibly, in vivo. Thus, if prenylation is to be regulated, this control must occur prior to lipid addition. At the moment, there is little evidence that the enzymatic activity of prenyl transferases can be modulated ...


Tissue Specific Expression And Regulation Of The Mitogen Regulated Protein Genes , John Tollen Fassett Jan 2000

Tissue Specific Expression And Regulation Of The Mitogen Regulated Protein Genes , John Tollen Fassett

Retrospective Theses and Dissertations

Mitogen Regulated Protein (MRP; also called Proliferin; or MRP/PLF) is a member of the Prolactin/Growth Hormone gene family. There is evidence that MRP/PLF is a uterine growth factor and an angiogenesis factor. Between four and six highly homologous MRP/PLF genes (mrp/plf ) exist in the mouse, but the significance of multiple genes has not been determined. MRP/Plf is produced at high levels during mid-gestation by the placenta, where expression is restricted to the trophoblastic giant cells. To better understand the regulation of the mrp/ plf genes in vivo, we have developed an assay to analyze ...


Two Dimensional Models Of Tumor Angiogenesis , Serdal Pamuk Jan 2000

Two Dimensional Models Of Tumor Angiogenesis , Serdal Pamuk

Retrospective Theses and Dissertations

Angiogenesis, the formation of new capillaries from pre-existing vessels, is essential for tumor progression. It is critical for the growth of primary cancers. In this thesis we present a new approach to angiogenesis, based on the theory of reinforced random walks, coupled with a Michaelis-Menten type mechanism. This views the endothelial cell receptors as the catalyst for transforming angiogenic factor into proteolytic enzyme in order to model the first stage. In our model we use a curvature-induced proliferation term for the endothelial cell equation. Our numerical results indicate that the proliferation of endothelial cells is high at the tip. Also ...


Characterization Of Intracellular Survival Of Mycobacterium Avium Subspecies Paratuberculosis In J774 Murine Macrophages , Jesse Michael Hostetter Jan 2000

Characterization Of Intracellular Survival Of Mycobacterium Avium Subspecies Paratuberculosis In J774 Murine Macrophages , Jesse Michael Hostetter

Retrospective Theses and Dissertations

Mycobacterium avium subspecies paratuberculosis (M. a. ptb) is the causative agent of Johne's disease, a progressive diarrheal disease of wild and domestic ruminants. Like other pathogenic species of mycobacteria, M. a. ptb is an intracellular pathogen of monocytes and monocyte-derived macrophages. In this dissertation we tested the hypothesis that M. a. ptb survives within macrophages by inhibition of acidification and maturation of the phagosomal compartment in which it resides;Chapter 1 consists of a general introduction and a literature review of recent reports concerning normal phagosomal maturation and maturation of the mycobacterial phagosome. Chapter 2 characterizes acidification of the ...


The Contributions Of The Hras C-Terminus And Its Lipid Modifications To Hras Signal Transduction Events And Membrane Binding , Michelle Ann Booden Jan 2000

The Contributions Of The Hras C-Terminus And Its Lipid Modifications To Hras Signal Transduction Events And Membrane Binding , Michelle Ann Booden

Retrospective Theses and Dissertations

In the GTP bound state, Ras proteins activate multiple downstream effector proteins, the combination of which regulate cell growth, differentiation, and changes in cell shape. However, Ras proteins must undergo C-terminal lipidation before they can support biological activity. Specifically, the C-terminus of the HRas protein must be modified by a farnesyl at Cys186 and two palmitates at Cys181 and Cys184. The current paradigm suggests that palmitate is not attached without prior farnesyl addition and that these post-translational lipid modifications are only necessary for membrane association. However, emerging evidence suggests that the C-terminus and its lipid modifications may also be responsible ...


Characterization Of Skeletor: A Novel Nuclear Protein Implicated In Mitotic Spindle Assembly , Diana Lee Walker Jan 2000

Characterization Of Skeletor: A Novel Nuclear Protein Implicated In Mitotic Spindle Assembly , Diana Lee Walker

Retrospective Theses and Dissertations

The mAb 2A labels Drosophila embryos in a novel, dynamic staining pattern that identifies a nuclear meshwork during interphase, which is remodeled to form a spindle structure at metaphase. This intriguing pattern made the antigens recognized by mAb 2A interesting targets for cloning and analysis, Skeletor was found to be encoded by a complex locus. Two alternatively spliced transcripts from the Skeletor locus were identified, Orf1b/Orf2 and Orf1a. Orf1b/Orf2 has an unusual structure, containing two overlapping open reading frames with coding potentials of 87 kD and 81 kD respectively. Analysis of Orf2 amino acid content reveals overall high ...


The Effects Of Methylamine Osmolytes On The Cytoskeleton Microtubule Assembly , Huang-Chun Tseng Jan 1999

The Effects Of Methylamine Osmolytes On The Cytoskeleton Microtubule Assembly , Huang-Chun Tseng

Retrospective Theses and Dissertations

Methylamine osmolytes are enriched in urea-rich cells. It is unclear, however, whether methylamines can promote microtubule assembly either in vitro or in cells. The osmolyte trimethylamine N-oxide (TMAO) at 200 mM increases the extent and the rate of formation of polymerized microtubule complex caused by microtubule-associated protein tau in vitro. Furthermore, TMAO counteracts the inhibition on the assembly caused by urea. Besides TMAO, betaine, another methylamine osmolyte, was found to have the same effects on MT as TMAO;Phosphorylation can affect the function of tau. Cyclic-AMP-dependent protein kinase (PKA)-phosphorylated tau does not promote tubulin assembly as judged by spectrophotometric ...


Molecular And Genetic Analysis Of Jil-1, A Chromatin Associated Protein Kinase Implicated In Transcriptional Regulation In Drosophila , Ye Jin Jan 1999

Molecular And Genetic Analysis Of Jil-1, A Chromatin Associated Protein Kinase Implicated In Transcriptional Regulation In Drosophila , Ye Jin

Retrospective Theses and Dissertations

Chromatin remodeling is an essential step for many chromatin-related fundamental cellular processes, such as gene replication, transcription, recombination and gene silencing. Two classes of protein complexes contribute to chromatin remodeling: protein complexes with ATPase activity and protein complexes capable of enzymatic modifications of chromosomal proteins, especially histones. Compared to well-studied histone acetylation which has been directly linked to gene transcription, the role of histone phosphorylation in chromatin remodeling for gene transcription is still poorly understood although there is some correlation between histone phosphorylation and gene transcription;A novel nuclear tandem protein kinase JIL-1 was cloned and identified in Kristen Johansen ...


Application Of Spectral Hole Burning To The Study Of In Vitro Cellular Systems , Nebojsa Milanovich Jan 1999

Application Of Spectral Hole Burning To The Study Of In Vitro Cellular Systems , Nebojsa Milanovich

Retrospective Theses and Dissertations

The high resolution spectroscopic technique of nonphotochemical hole burning (NPHB) was applied to the study of in vitro cellular systems. Suspensions of two well-characterized cell lines were used for these studies: (1) MCF-10F cells, a normal human breast epithelial cell line, and (2) MCF-7 cells, a human breast adenocarcinoma cell line. Both cell lines were stained with the dye aluminum phthalocyanine tetrasulfonate (APT) and prepared for spectroscopic study at liquid helium temperatures. Routinely measured hole burning parameters were obtained for the two cell types and compared in order to differentiate between physical properties of normal and cancer cells;A comparison ...


Novel G-Dna Binding Proteins From The Ciliate Tetrahymena Thermophila: Purification, Characterization, Cloning And Functional Analyses , Quan Lu Jan 1999

Novel G-Dna Binding Proteins From The Ciliate Tetrahymena Thermophila: Purification, Characterization, Cloning And Functional Analyses , Quan Lu

Retrospective Theses and Dissertations

G-DNA is a family of novel four-stranded DNA structures characterized by motifs called G-quartets. Evidence is growing to suggest that G-DNA exists and plays biological roles in vivo. In order to further elucidate the functions of G-DNA, we have studied proteins that specifically bind to the DNA structure;Two G-DNA binding activities, TGPI and TGP3, were purified from the ciliate Tetrahymena thermophila. Based on the peptide sequences obtained from direct internal peptide sequencing, the cDNAs coding for the genes were cloned. Deduced protein sequences showed that TGP1 and TGP3 are novel proteins but share significant homology with each other. Furthermore ...


Fatty Acid Modification Of Cells In Culture By Overexpression Of Exogenous Desaturases , Travis Jay Knight Jan 1999

Fatty Acid Modification Of Cells In Culture By Overexpression Of Exogenous Desaturases , Travis Jay Knight

Retrospective Theses and Dissertations

COS-1 cells were transfected transiently with expression vectors encoding stearoyl-acyl-carrier-protein desaturase (SACPD) from castor bean, stearoyl-CoA desaturase (SCD) from mice, and a control vector containing SACPD cDNA in reverse orientation. The hypothesis was that both exogenous desaturases would be active in COS-1 cells, thereby increasing the proportion of monounsaturated fatty acids produced by the cells. Messenger RNA and anti-myc immunoreactive proteins were detected at 12 and 24 hours post-transfection respectively and increased through 48 hours post-transfection. When acetate was used as the fatty acid precursor in cultures for a 24-hour period starting 24 hours post-transfection, the ratio of monounsaturated to ...


Dynamic Changes In The Localization Of Synapse Associated Proteins During Development And Differentiation Of The Mammalian Retina , Mary Heather West Greenlee Jan 1999

Dynamic Changes In The Localization Of Synapse Associated Proteins During Development And Differentiation Of The Mammalian Retina , Mary Heather West Greenlee

Retrospective Theses and Dissertations

We have examined the developmental distribution and differential localization of presynaptic terminal associated proteins in the mammalian retina. We have used antibodies specific for synaptic vesicle associated proteins Synaptotagmin, Rab 3A, Synaptophysin and Synaptobrevin, and presynaptic terminal membrane associated proteins SNAP-25 and Syntaxin, to characterize their spatio-temporal distribution during retinal differentiation and in the mature retina;The vertebrate retina has a laminar organization consisting of three cellular layers separated by two synaptic layers, the inner piexiform layer and the outer plexiform layer. In general, immunoreactivity for presynaptic terminal associated proteins was first observed in cellular layers, and as differentiation progressed ...


Reversible Palmitoylation Of H-Ras Is Affected By Oxidants And Activation State , Tara Lynn Baker Jan 1998

Reversible Palmitoylation Of H-Ras Is Affected By Oxidants And Activation State , Tara Lynn Baker

Retrospective Theses and Dissertations

Signal transduction organizes cell growth, differentiation, and apoptosis. One component of several signaling pathways leading to these outcomes is the Ras protein. Ras is a small GTPase, binding GTP in an active conformation and GDP in an inactive conformation. Upon nucleotide binding, the conformation of Ras changes so that its effector region can bind to proteins directly downstream in several pathways. Several GTP-bound mutants have been discovered, and an activated Ras mutant has been found in at least 50% of human tumors;Ras must reside at the membrane in order to interact with effector proteins. Binding at the plasma membrane ...


Gene Expression Studies Of Murine Pregnancy Associated Granulated Metrial Gland And Decidual Cells , Melissa Phillips Allen Jan 1997

Gene Expression Studies Of Murine Pregnancy Associated Granulated Metrial Gland And Decidual Cells , Melissa Phillips Allen

Retrospective Theses and Dissertations

During pregnancy in viviparous mammals, the maternal decidua develops between the embryo and the uterine endometrium. This dissertation describes research on two different cell types present within the rodent decidua during pregnancy, namely, granulated metrial gland (GMG) cells and decidual cells;GMG cells are natural killer cells that proliferate and differentiate within the murine uterus during pregnancy. Their differentiation is associated with the accumulation of cytolytic mediators within cytoplasmic granules. The signaling mechanisms required for GMG cell differentiation, however, are largely unknown. In this study, expression of the genes coding for granzymes D, E, F, and G (granzymes D-G) was ...


Suppressor Analysis Of The Protein Kinase Elm1p, An Enzyme Involved In The Regulation Of Yeast Morphology , Nicholas Patrick Edgington Jan 1997

Suppressor Analysis Of The Protein Kinase Elm1p, An Enzyme Involved In The Regulation Of Yeast Morphology , Nicholas Patrick Edgington

Retrospective Theses and Dissertations

Saccharomyces cerevisiae is an ascomycete that has several developmental options, with concomitant morphological changes, that depend on cell type and nutrient status. In response to these signals, vegetative Saccharomyces cerevisiae cells assume one of two distinct morphologies, the yeast form or the filamentous form. Molecules affecting this morphogenetic response were identified by analyzing transposon-induced or spontaneous suppressor mutations that restore yeast form growth to a strain that constitutively exhibits filamentous form characteristics owing to mutation of the protein kinase Elm1p. One transposon-tagged mutation was isolated and is allelic to the negative regulatory subunit Bcy1p, thus activation of cAMP dependent protein ...