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

Investigation Of The Cellular And Molecular Mechanisms Of Radiation-Induced Bystander Effects, Hayley Furlong Jan 2014

Investigation Of The Cellular And Molecular Mechanisms Of Radiation-Induced Bystander Effects, Hayley Furlong

Doctoral

The overall aim of this study was to investigate the cellular and molecular mechanisms involved in radiation-induced bystander effects in HaCaT cells, predominantly at low-doses of irradiation. They do not follow the original dose-response theory and exhibit a unique cascade of signalling events, which are under intense investigation for radiation risk purposes. An in vitro system was first used to observe the bystander effect, comparing two cell viability assays while measuring apoptotic cell death in these known reporter HaCaT cells and established the most sensitive assay for bystander responses Downstream bystander signalling events were then investigated through gene expression studies ...


Mechanisms Of Bes1-Regulated Gene Expression Downstream Of Brassinosteroid Signaling In Arabidopsis Thaliana, Xiaofei Yu Jan 2008

Mechanisms Of Bes1-Regulated Gene Expression Downstream Of Brassinosteroid Signaling In Arabidopsis Thaliana, Xiaofei Yu

Retrospective Theses and Dissertations

Brassinosteroids (BRs), the plant steroid hormones, play an important role in mediating plant responses to developmental and environmental cues. BRs signal through a membrane receptor BRI1 and a GSK3 kinase BIN2 to control the activity of BES1/BZR1 family transcription factors. To understand how BES1 regulates gene expression, I looked into both trans-acting protein factors and cis-acting DNA elements that affect BES1 functions, by yeast genetic screen and chromatin immunoprecipitation coupled with DNA microarray (ChIP-chip), respectively. We identified 1609 BES1 direct target genes and discovered conserved DNA motifs in BES1 binding regions. We also showed that BES1 target genes were ...


Molecular Interactions Of The Mammalian Intermediate Filament Protein Synemin With Cytoskeletal Proteins Present In Adhesion Sites, Ning Sun Jan 2008

Molecular Interactions Of The Mammalian Intermediate Filament Protein Synemin With Cytoskeletal Proteins Present In Adhesion Sites, Ning Sun

Retrospective Theses and Dissertations

The type VI intermediate filament (IF) protein synemin is a very large, unique member of the IF protein superfamily. Synemin associates with the major type III IF protein desmin and/or vimentin forming heteropolymeric intermediate filaments (IFs) within mammalian muscle cells. Previous studies in our lab showed that avian synemin interacts with vinculin and alpha-actinin, both of which are cytoskeletal proteins present in adhesion sites such as the focal adhesions within cells. Thus, synemin may link the heteropolymeric IFs to adhesion sites within mammalian muscle cells or within some non-muscle cells that express synemin. At least two isoforms of synemin ...


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 ...


The Roles Of Lcn2 In The Inflammatory Lung And Liver, Yinghua Liu Jan 2007

The Roles Of Lcn2 In The Inflammatory Lung And Liver, Yinghua Liu

Retrospective Theses and Dissertations

Uterocalin (Lcn2; also called 24p3, SIP24, or siderocalin and abbreviated as Utc) is an acute phase protein, for which the physiological function remains to be determined. Basal Utc expression is highest in the uterus, mammary gland and lung, which are three tissues with direct exposure to the diverse bacterial flora of the external environment. The demonstrated ability to bind siderophores is one means by which Utc can provide protection against pathogenic bacteria. However, its specificity for siderophores limits the ability of Utc to ward off pathogens. Epithelial tissues that interact with the external environment are exposed to many different nonpathogenic ...


Characterization Of Rns2, An S-Like Rnase In Arabidopsis Thaliana Suggests Role In Phosphate Recycling, Saralyn Ohanian Jan 2007

Characterization Of Rns2, An S-Like Rnase In Arabidopsis Thaliana Suggests Role In Phosphate Recycling, Saralyn Ohanian

Retrospective Theses and Dissertations

Ribonucleases play important biological roles within all organisms but many have not been well characterized. The family of T2 RNases is well-conserved throughout the kingdoms of life and yet their properties and functions are not well understood. RNS2 is one of five such RNases found in Arabidopsis, and preliminary evidence shows that it may be involved in phosphate recycling and localized to an intracellular compartment. Using rns2 knock-out mutant plants, I showed that RNS2 has an effect on flowering time during times of phosphate starvation. I also showed that RNS2 is localized to the ER, more specifically, to ER-bodies. To ...


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 ...


Mechanism Of Cap-Independent Translation By Long Distance Kissing Stem-Loop Interactions In Plant Viral Rnas, Aurélie Mamisoa Rakotondrafara Jan 2007

Mechanism Of Cap-Independent Translation By Long Distance Kissing Stem-Loop Interactions In Plant Viral Rnas, Aurélie Mamisoa Rakotondrafara

Retrospective Theses and Dissertations

While the presence of a 5' cap and a 3' poly(A) tail are key elements for efficient translation of eukaryotic mRNAs, many viral mRNAs lack one or both of such structures and yet translate efficiently. Owing to the absence of a 5' cap, Barley yellow dwarf virus (BYDV, Luteoviridae family) genomic and subgenomic RNA1 rely on a cap-independent translation element (BTE), which is an RNA domain capable of promoting translation. In contrast to an internal ribosome entry site (IRES), the BTE is located at the 3' end of the viral mRNA, while translation initiation occurs at the 5' end ...


The Role Of The Integrase C-Terminus In Replication And Targeted Integration Of The Yeast Retrotransposon Ty5, Troy Leon Brady Jan 2007

The Role Of The Integrase C-Terminus In Replication And Targeted Integration Of The Yeast Retrotransposon Ty5, Troy Leon Brady

Retrospective Theses and Dissertations

Mobile genetic elements have the inherent potential to shape the genomes of their hosts. The retroelements, which include the retrotransposons and retroviruses, are a particularly abundant class of mobile elements. The site of retroelement insertion in the host genome is largely determined by the element-encoded protein integrase (IN). Research presented here addresses three aspects of IN from the retrotransposon Ty5: the function of a conserved domain (GKGY) in the IN C-terminus, the role of IN post-translational modification in targeted integration, and the origin of the Ty5 targeting mechanism.;Sequence analysis of a conserved domain (GKGY) found in the C-termini of ...


Identification Of Stbel5 Rna As A Long-Distance Mobile Signal In Short-Day Facilitated Tuber Formation , Yueyue Yu Jan 2006

Identification Of Stbel5 Rna As A Long-Distance Mobile Signal In Short-Day Facilitated Tuber Formation , Yueyue Yu

Retrospective Theses and Dissertations

In potato, the BEL1-like transcription factor, StBEL5 and its protein partner POTH1, regulate tuber formation by mediating hormone levels in the stolon tip. Heterografting experiments show that StBEL5 mRNA can move across the graft union to localize in stolon tips and enhance tuber formation. Over-expression of StBEL5 full-length transcripts including the untranslated regions (UTRs) endows transgenic lines with the capacity to overcome the long-day inhibitory effects on tuber formation.;In this study, the precise localization of endogenous StBEL5 mRNA and other gene specific transcripts in the vascular tissues were determined by laser microdissection coupled to laser pressure catapulting (LMPC) and ...


Rapid Cellular Signalling And Dose Dependent Cellular Pathways Induced In Hpv-G Cells Exposed To Medium Borne Factors, Paula Maguire Jan 2006

Rapid Cellular Signalling And Dose Dependent Cellular Pathways Induced In Hpv-G Cells Exposed To Medium Borne Factors, Paula Maguire

Doctoral

The aim of this thesis was to investigate rapid signalling events and dose dependent activation of cellular pathways in unirradiated human keratinocyte (HPV-G) cells exposed to bystander signal molecules in vivo and in vitro. HPV-G cells were exposed to irradiated cell conditioned medium (ICCM) ranging from 5mGy to 5Gy ICCM. Cellular events investigated included intercellular calcium, reactive oxygen species (ROS), mitochondrial membrane potential, cytochrome c release, caspase 3 and 8 activity, Bcl-2 expression and mitochondrial proliferation. Apoptosis levels and clonogenic survival were also determined in order to understand the cellular outcome of the activated pathways. It was found that exposure ...


Genetic And Molecular Analysis Of Starch Synthases Functions In Maize And Arabidopsis , Xiaoli Zhang Jan 2006

Genetic And Molecular Analysis Of Starch Synthases Functions In Maize And Arabidopsis , Xiaoli Zhang

Retrospective Theses and Dissertations

Understanding the specific functions played by individual starch synthase isoforms in maize and Arabidopsis will provide important evidence for how highly organized starch structure is made. Starch synthases (SS) catalyze the transfer of the glucosyl moiety from ADP-Glc to the terminus of a growing alpha-(1, 4)-linked glucan linear chain. At least five classes of SSs are identified in higher species, referred to as GBSS, SSI, SSII, SSIII, and SSIVN. They have high similarity in the catalytic and starch-binding domains of the C-termini but differ at their N-termini. All of these enzymes are highly conserved in plant kingdom, which ...


Functional Analysis Of The Crinkly4 Gene Family In Arabidopsis Thaliana And Viviparous1 Promoter In Zea Mays , Xueyuan Cao Jan 2005

Functional Analysis Of The Crinkly4 Gene Family In Arabidopsis Thaliana And Viviparous1 Promoter In Zea Mays , Xueyuan Cao

Retrospective Theses and Dissertations

The cereal endosperm is an excellent system to study cell differentiation and fate specification. The aleurone of maize is one cell layer and requires continuous positional cues to specify and maintain its identity. A genetic hierarchy is implicated in this process. CRINKLY4 ( Cr4), a receptor-like kinase, belongs to cell fate-specifying genes and is required to specify aleurone cell identity. Viviparous1 ( Vp1), a B3 domain-containing transcription factor, functions late in development to regulate the expression of C1 in aleurone cells. It also plays an important regulatory role in late embryogenesis and seed maturation with abscisic acid (ABA).;The Arabidopsis genome encodes ...


Genetic Profiling Of Mycoplasma Hyopneumoniae , Melissa L. Madsen Jan 2005

Genetic Profiling Of Mycoplasma Hyopneumoniae , Melissa L. Madsen

Retrospective Theses and Dissertations

A microarray was constructed and applied to transcriptional profiling and genetic variation studies of Mycoplasma hyopneumoniae. The genome sequence enabled the construction of the microarray to allow a global approach to understanding fundamental processes in M. hyopneumoniae . These studies focused on whether M. hyopneumoniae regulates its genes under different environmental conditions and if genetic changes can be correlated with virulence. The microarray consisted of 632 open reading frames represented by polymerase chain reaction products and were used in a two-color experimental design. Data were analyzed using a mixed linear statistical model. Unique features implemented in these studies included the printing ...


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 ...


Investigation Of The Molecular Mechanism Of Fertility Restoration In Texas Cytoplasm Maize , David Stewart Skibbe Jan 2004

Investigation Of The Molecular Mechanism Of Fertility Restoration In Texas Cytoplasm Maize , David Stewart Skibbe

Retrospective Theses and Dissertations

Cytoplasmic male sterility (cms) is a maternally inherited inability to produce viable pollen. In Texas (T)-cytoplasm maize, the combined action of two restorer of fertility genes, rfl and rfla , can overcome the male sterile phenotype. Previous research established rf2a encodes a mitochondrial aldehyde dehydrogenase (ALDH) with broad substrate specificity. This broad substrate specificity complicates determining the molecular mechanism of rf2a-mediated fertility restoration. In response, a combination of transgenic, biochemical, reverse genetic, and genomic approaches were utilized. Three additional functional maize ALDH genes (rf2b, rf2c, and rf2d) with differing substrate specificities were identified. Each ALDH gene was characterized via in ...


Molecular And Functional Analysis Of Drosophila Hillarin And Its Leech Homolog , Yun Ji Jan 2004

Molecular And Functional Analysis Of Drosophila Hillarin And Its Leech Homolog , Yun Ji

Retrospective Theses and Dissertations

This thesis describes the molecular and functional analysis of the leech Hillarin and its Drosophila homolog D-hil. Leech Hillarin was identified by screening a leech expression library with the mAb Lan3-15, which specifically labels the axon hillock region of leech neurons. Database searches revealed that leech Hillarin has a number of potential homologs in a variety of organisms such as yeast, cyanobacterium, fly, nematode, mouse and human and that these proteins share two novel protein domains, the W180 domain and the H domain. The W180 domain is enriched with tryptophans whereas the H domain shares high number of invariant residues ...


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 ...


Herpes Virus Icp47 And Us11 Suppression Of Ctl Activity Adapted For Use In Gene Therapy , Thomas Joseph Radosevich Jan 2003

Herpes Virus Icp47 And Us11 Suppression Of Ctl Activity Adapted For Use In Gene Therapy , Thomas Joseph Radosevich

Retrospective Theses and Dissertations

A major stumbling block encountered in gene therapy clinical trials has been the rapid destruction of the therapeutic product by the host's immune response. The goal of this work is to diminish the host Cytotoxic T Lymphocyte (CTL) response to gene therapy transgenes and transduced cells by incorporating immunosuppression genes into gene therapy vectors. The processing and presentation of antigens through the class I Major Histocompatibility Complex (class I MHC) pathway is known to be an early response to viral infection. Disruption of the class I MHC pathway results in a decrease of the CD8+ CTL response and prolongs ...


Navigating Heterochromatin , Peter Fuerst Jan 2003

Navigating Heterochromatin , Peter Fuerst

Retrospective Theses and Dissertations

The condensed structure of heterochromatin differs significantly from euchromatin and DNA bound in heterochromatin is generally not transcriptionally active. Transcriptional silencing allows the control of gene expression and affords a novel mechanism of defense against genomic parasites. In addition, the physical structure of heterochromatin plays a direct role by contributing to centromere function in many eukaryotes. Mechanisms by which heterochromatin is established and maintained are only partly understood at this time. By studying the interaction of Ty5, a retrotransposon that integrates preferentially into heterochromatin-bound DNA, some of the basic biology of heterochromatin and the proteins that compose it were elucidated ...


Genetic And Phenotypic Variation Of The Equine Infectious Anemia Virus Surface Unit Envelope Glycoprotein During Disease Progression , Brett Alan Sponseller Jan 2003

Genetic And Phenotypic Variation Of The Equine Infectious Anemia Virus Surface Unit Envelope Glycoprotein During Disease Progression , Brett Alan Sponseller

Retrospective Theses and Dissertations

Lentiviruses are single-stranded RNA viruses generally associated with chronic diseases of the immune and central nervous systems. In contrast to the insidious, progressive nature of most lentiviral diseases, equine infectious anemia virus (EIAV) infection results in rapid onset of a variable disease course in equids. Acute disease is accompanied with high-titered viremia, thrombocytopenia, fever, depression, and inappetance. The chronic stage is usually characterized by recurrent episodes of disease. Equids that survive recurrent disease episodes progress to the inapparent stage of disease where no clinical signs are evident; however, there is persistent, ongoing virus replication. Lentiviruses exist within the host as ...


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 ...


Transcription Factors Involved In The Development Of Potato (Solanum Tuberosum L) , Faye Michelle Rosin Jan 2002

Transcription Factors Involved In The Development Of Potato (Solanum Tuberosum L) , Faye Michelle Rosin

Retrospective Theses and Dissertations

The objective of this study was to gain insight into how classes of regulatory genes affect the growth and development of potato, particularly, the molecular processes of tuberization. This was accomplished by generating transgenic potato plants that overexpress the homeobox gene, POTH1 , and by using an antisense approach to suppress levels of the MADS box gene, POTM1.;POTH1 was shown to be involved in vegetative pattern formation via mediation of hormone levels. Overexpression of POTH1 resulted in dwarf plants with a 'mouse-ear' leaf phenotype. Leaves were heart-shaped with a decreased midvein and palmate venation. POTH1 overexpression lines exhibited an increase ...


Roles Of The Mitogen-Induced Proteins, Mitogen Regulated Protein/Proliferin And 24p3/Uterocalin, During Mouse Development , Pierig Jean-Marie Lepont Jan 2002

Roles Of The Mitogen-Induced Proteins, Mitogen Regulated Protein/Proliferin And 24p3/Uterocalin, During Mouse Development , Pierig Jean-Marie Lepont

Retrospective Theses and Dissertations

Mitogens, serum and growth factors, induce the secretion of several proteins in cell cultures. Mitogen regulated protein/proliferin (MRP/PLF) is one such protein secreted from 3T3 cells 20 hours after the addition of fibroblast growth factor (FGF). 24p3/uterocalin is another protein induced 10 hours after FGF addition. When combined with cycloheximide, 24p3/uterocalin secretion is increased by 5 fold.;MRP/PLFs are glycoproteins, belonging to the prolactin-growth hormone family, expressed at high concentration during mid-gestation in the mouse placenta. MRP/PLFs are thought to stimulate angiogenesis in the placenta and the uterus, and stimulate uterine cell growth during ...


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 ...


Studying The Replication Mechanism Of The Yeast Retrotransposon Ty5 By Molecular And Computational Approaches, Xiang Gao Jan 2001

Studying The Replication Mechanism Of The Yeast Retrotransposon Ty5 By Molecular And Computational Approaches, Xiang Gao

Retrospective Theses and Dissertations

The yeast retrotransposon Ty5 is a Ty1/copia element. It is in the Hemivirus genus of the Pseudoviridae family. The ability to genetically manipulate retrotransposons and the yeast host cell was taken advantage of to explore replication mechanisms unique to Ty5 and common to most retrotransposons. Because of the abundance and diversity of retroelement sequences, along with the fact that many retroelement enzymes have evolved unique functional specificities, computational approaches were also developed to study functional divergence in replication. By screening a randomly mutagenized Ty5 library, two mutations (Y68C, D252N) causing higher transposition frequencies were identified. Both mutations increased Ty5 ...


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 ...


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 ...


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 ...