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Articles 31 - 60 of 135

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

Role Of Phosphorylation In The Regulation Of Prmt5, Alexsandra B. Espejo Sep 2016

Role Of Phosphorylation In The Regulation Of Prmt5, Alexsandra B. Espejo

UT GSBS Dissertations and Theses (Open Access)

PRMT5 is a member of a group of proteins that mediate arginine methylation. It is involved in diverse cellular processes, including cell differentiation, splicing, transcription elongation and epigenetic silencing, and its expression is dysregulated in many cancers. Due to its pleiotropic functions, PRMT5 is subject to multi-level regulation. Post-translational modification (PTM) of proteins can modulate an array of cellular processes by regulating both protein interactions and protein structural changes. PRMT5 is commonly found associated with other proteins; these interactions seem to control both its catalytic activity and its substrate specificity. Recently, it became clear that PRMT5 is phosphorylated at a ...


Investigating The Roles Of Δnp63 As A Suppressor Of Migration, Invasion, And Metastasis, Ramon E. Flores Gonzalez Aug 2016

Investigating The Roles Of Δnp63 As A Suppressor Of Migration, Invasion, And Metastasis, Ramon E. Flores Gonzalez

UT GSBS Dissertations and Theses (Open Access)

Cancer is one of the leading causes of death and disease in the world. Considerable resources are spent to study and understand cancer, with the hope of developing new treatments and eventually cures that will help millions of people. Efforts to understand cancer are hindered by its inherent complexity and instability. Nonetheless, understanding the basics of tumor development and progression are the key to focused on studying the role of ΔNp63 in cancer, a p53 family member known to be involved in epithelial development, microRNA biogenesis, and stem cell maintenance. Using the strength of in vivo mouse models, we found ...


Circumventing Cisplatin Resistance In Ovarian Cancers Through Reactivation Of P53 By Non-Cross-Resistant Platinum Analogs, Michelle Martinez-Rivera Aug 2016

Circumventing Cisplatin Resistance In Ovarian Cancers Through Reactivation Of P53 By Non-Cross-Resistant Platinum Analogs, Michelle Martinez-Rivera

UT GSBS Dissertations and Theses (Open Access)

Abstract

CIRCUMVENTING CISPLATIN RESISTANCE IN OVARIAN CANCERS THROUGH REACTIVATION OF P53 BY NON-CROSS-RESISTANT PLATINUM ANALOGS

Michelle Martinez-Rivera, B.S.

Advisory Professor: Zahid H. Siddik, Ph.D.

Cisplatin (cis-Pt), an anticancer platinum (Pt) drug, is used widely in the treatment of several malignancies, such as ovarian cancer. This Pt compound induces DNA damage, which results in p53 activation through post-translational modifications, mainly phosphorylation, culminating in execution of programmed cell-death. However, despite initial therapeutic response to cis-Pt, clinical resistance to this drug emerges leading to disease progression. Pt-resistance phenotypes have been associated with dysfunction in the p53 signaling pathway. Therefore, an effort ...


¬¬Define The Epigenetic Profiles And Subtype-Specific Genes Of Breast Cancer, Wenqian Li Aug 2016

¬¬Define The Epigenetic Profiles And Subtype-Specific Genes Of Breast Cancer, Wenqian Li

UT GSBS Dissertations and Theses (Open Access)

Molecular profiling has identified 5 distinct subtypes of breast cancer, luminal A, luminal B, HER2-enriched, basal-like, and claudin-low breast cancer. These 5 subtypes correlate with hormone response, patient prognosis, and response to therapy. Although steady state gene expression patterns have been explored using expression microarrays, very little is known about the initial, disease-driving transcriptional changes in these cancers or epigenetic changes associated with the differential gene expression signatures. Defining these changes may provide new insights into the mechanisms by which these subtypes arise, as well as new avenues for breast cancer prevention, diagnosis, and treatment. Using Chromatin Immunoprecipitation sequencing and ...


Defining The Functions Of Usp22 And Usp44 In Regulation Of H2bub1 Levels, Xianjiang Lan Aug 2016

Defining The Functions Of Usp22 And Usp44 In Regulation Of H2bub1 Levels, Xianjiang Lan

UT GSBS Dissertations and Theses (Open Access)

Aberrant levels of histone ubiquitination are involved in various human diseases including neurodegenerative disorders and cancers. Particularly, Histone H2B monoubiquitination (H2Bub1) is highly associated with gene regulation in both normal cells and diseases. Many deubiquitinases (mainly USPs) are defined to regulate global H2Bub1 levels. However, how these USPs are regulated and how they contribute to diseases are not well understood.

USP22, part of the deubiquitination module (DUBm) in the SAGA complex, is a well-defined regulator of H2Bub1 levels. ATXN7, another crucial subunit of the SAGA DUBm, is involved in a neurodegenerative disease, spinocerebellar ataxia type 7 (SCA7), due to a ...


The Roles Of Malt1 In Nf-Κb Activation And Solid Tumor Progression, Deng Pan May 2016

The Roles Of Malt1 In Nf-Κb Activation And Solid Tumor Progression, Deng Pan

UT GSBS Dissertations and Theses (Open Access)

The transcription factor NF-κB plays a central role in many aspects of biological processes and diseases, such as inflammation and cancer. Although it has been suggested thatNF-κB is critical in tumorigenesis and tumor progression, the molecular mechanism by which NF-κB is activated in solid tumor remains largely unknown. In the current work, we focus on growth factor receptor-induced NF-κB activation and tumor progression, including epidermal growth factor receptor (EGFR)-induced NF-κB in lung cancer and heregulin receptor (HER2)-induced NF-κB in breast cancer. We found that Mucosa-associated lymphoma translocation protein 1 (MALT1), also known as paracaspase, is required for EGFR-induced ...


Developing And Using Methyl-Specific Antibodies To Study The Biological Roles Of Arginine Methylation, Vidyasiri Vemulapalli May 2016

Developing And Using Methyl-Specific Antibodies To Study The Biological Roles Of Arginine Methylation, Vidyasiri Vemulapalli

UT GSBS Dissertations and Theses (Open Access)

Arginine residues can be modified in three different ways to produce asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and monomethylarginine (MMA). These modifications are catalyzed by a family of nine protein arginine methyltransferases (PRMT1-9), which are of three types (I, II, and III). The majority of Type I enzymes asymmetrically dimethylate Glycine- and Arginine-rich (GAR) motifs, except for PRMT4, which methylates Proline-, Glycine-, and Methionine-rich (PGM) motifs. The same substrates (GAR or PGM motifs) can also be dimethylated by PRMT5 in a symmetric fashion. However, it is not clear whether there are dedicated residues within these motifs for ADMA and SDMA ...


Cll Metabolism Is Regulated By Prognostic Factors, Modulated By Stroma And Abrogated By Pi3k Inhibition, Hima Vangapandu May 2016

Cll Metabolism Is Regulated By Prognostic Factors, Modulated By Stroma And Abrogated By Pi3k Inhibition, Hima Vangapandu

UT GSBS Dissertations and Theses (Open Access)

Metabolism of chronic lymphocytic leukemia (CLL), a disease characterized by the relentless accumulation of mature B cells has been little explored. Bone marrow stromal cells provide a survival benefit to CLL cells, in part through PI3K/AKT pathway. Compared with proliferative B-cell lines, metabolic fluxes of oxygen and lactate were low in quiescent malignant B lymphocytes from CLL patients. Glycolysis (extracellular acidification rate, ECAR) was consistently low in CLL samples, but oxygen consumption (OCR) varied considerably. Higher OCR was associated with poor prognostic factors such as ZAP 70 positivity, unmutated IgVH, high β2M levels, and higher Rai stage. Co-culture with ...


Preeclampsia: The Roles Of Acute Inflammation And Intrauterine Stress, Nicholas Parchim May 2016

Preeclampsia: The Roles Of Acute Inflammation And Intrauterine Stress, Nicholas Parchim

UT GSBS Dissertations and Theses (Open Access)

Preeclampsia (PE) is a severe, acute disease of pregnancy affecting approximately 8% of pregnant women after week 20 of gestation. PE is characterized by hypertension and renal damage reflected by proteinuria and has significant morbidity to both mother and fetus. Maternal symptoms range from headaches, nausea, edema, to visual changes, but once maternal symptoms present, damage to the fetus has begun. Mothers who progress untreated through the disease can also experience a condition called eclampsia characterized by seizure, coma, and, ultimately, death. PE-affected newborns experience features similar to prematurity—abnormal lung and renal development, intrauterine growth retardation (IUGR), and, possibly ...


Mechanisms Of Regulation Of Tau Ires Mediated Translation, Niza Nemkul May 2016

Mechanisms Of Regulation Of Tau Ires Mediated Translation, Niza Nemkul

UT GSBS Dissertations and Theses (Open Access)

The translation of most eukaryotic mRNAs occurs in a cap-dependent manner. However, a subset of mRNAs are capable of initiating translation in a cap-independent manner by utilizing sequences in their 5’ UTR called IRES. It was previously shown that the 5’ UTR of the tau mRNA contains an IRES. In this study I show that IRES dependent translation of tau IRES is regulated at multiple levels in order to regulate the expression of the tau protein.

Tau protein is ubiquitously expressed but is concentrated in the brain. In this study, I utilized neural and non-neural cell lines to show that ...


Preventing Thymus Involution In K5.Cyclin D1 Transgenic Mice Sustains The Naïve T Cell Compartment With Age, Michelle L. Bolner Dec 2015

Preventing Thymus Involution In K5.Cyclin D1 Transgenic Mice Sustains The Naïve T Cell Compartment With Age, Michelle L. Bolner

UT GSBS Dissertations and Theses (Open Access)

The thymus maintains T cell receptor (TCR) repertoire diversity through perpetual release of self-MHC restricted naive T cells. However, thymus involution during the aging process reduces naïve T cell output, leading to defective immune responsiveness to newly encountered antigens. We have found that early thymus involution precipitates the age-associated shift favoring memory T cell dominancy in young control mice. Furthermore, we have shown that age-related thymus involution is prevented in mice expressing a keratin 5 promoter-driven Cyclin D1 (K5.D1) transgene in thymic epithelial cells (TECs). Thymopoiesis occurs normally in K5.D1 transgenic thymi and sustains T cell output to ...


The Tumor Suppressor Notch Inhibits Head And Neck Squamous Cell Carcinoma (Hnscc) Tumor Growth And Progression By Modulating Proto-Oncogenes Axl And Ctnnal1 (Α-Catulin), Shhyam Moorthy, Shhyam Moorthy Dec 2015

The Tumor Suppressor Notch Inhibits Head And Neck Squamous Cell Carcinoma (Hnscc) Tumor Growth And Progression By Modulating Proto-Oncogenes Axl And Ctnnal1 (Α-Catulin), Shhyam Moorthy, Shhyam Moorthy

UT GSBS Dissertations and Theses (Open Access)

Background: Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common malignancy worldwide, with roughly 300,000 cancer related deaths occurring globally each year. The survival of patients with HNSCC has not changed significantly over the past decade, leading investigators to search for promising molecular targets. To identify new treatment targets and biomarkers that could better guide therapy, we previously characterized the genomic alterations from primary HNSCC patient samples. We were among the first to discover that NOTCH1 is one of the most frequently mutated genes in this cancer type. The spectrum of inactivating NOTCH1 mutations in HNSCC ...


Molecular Regulation Of Vascular Calcification In Murine Models Of Atherosclerosis, Shanshan Gao Dec 2015

Molecular Regulation Of Vascular Calcification In Murine Models Of Atherosclerosis, Shanshan Gao

UT GSBS Dissertations and Theses (Open Access)

Background: Calcification occurs often in the atherosclerotic lesions of patients with coronary heart disease and animals with hypercholesterolemia, such as apolipoprotein-E deficient (ApoE-/-) mice. However, the mechanism(s) underlying the development of calcification in atherosclerosis remains unclear. ApoE acts as a lipid transporter, but also has been recognized as a potential regulator of osteogenesis. Little information is available as to whether ApoE has any direct impact on osteogenesis and calcification in vascular smooth muscle cells (VSMC). Several signal transduction pathways play a role in regulation of calcification, including the Wnt/β-catenin system and potentially GTAP, an ubiquitin-conjugating enzyme responsible for ...


Normal Glycolytic Enzyme Activity Is Critical For Hypoxia Inducible Factor-1a Activity And Provides Novel Targets For Inhibiting Tumor Growth, Geoffrey Grandjean Phd Dec 2015

Normal Glycolytic Enzyme Activity Is Critical For Hypoxia Inducible Factor-1a Activity And Provides Novel Targets For Inhibiting Tumor Growth, Geoffrey Grandjean Phd

UT GSBS Dissertations and Theses (Open Access)

Normal Glycolytic Enzyme Activity is Critical for Hypoxia Inducible Factor-1α Activity and Provides Novel Targets for Inhibiting Tumor Growth

By Geoffrey Grandjean

Advisory Professor: Garth Powis, D. Phil

Unique to proliferating cancer cells is the observation that their increased need for energy is provided by a high rate of glycolysis followed by lactic acid fermentation in a process known as the Warburg Effect, a process many times less efficient than oxidative phosphorylation employed by normal cells to satisfy a similar energy demand [1]. This high rate of glycolysis occurs regardless of the concentration of oxygen in the cell and is ...


Structure And Composition Of Postsynaptic Densities, Madeline Farley Aug 2015

Structure And Composition Of Postsynaptic Densities, Madeline Farley

UT GSBS Dissertations and Theses (Open Access)

Communication between neurons within the brain occurs at chemical synapses and is fundamental for all brain functions. Modulation of the strength of communication is controlled by both presynaptic and postsynaptic mechanisms and is termed synaptic plasticity. One postsynaptic structure postulated to regulate synaptic strength is the postsynaptic density (PSD), a large electron dense protein complex located just below the synaptic membrane. The PSD, which is composed of signaling, scaffold and cytoskeletal proteins, supports and organizes neurotransmitter receptors within the synaptic membrane in addition to bridging signaling with the actin cytoskeletal network. The protein composition and structure of PSDs is known ...


Prophylactic Cranial Irradiation Reduces The Incidence Of Brain Metastasis In A Mouse Model Of Metastatic Breast Cancer, Daniel L. Smith Aug 2015

Prophylactic Cranial Irradiation Reduces The Incidence Of Brain Metastasis In A Mouse Model Of Metastatic Breast Cancer, Daniel L. Smith

UT GSBS Dissertations and Theses (Open Access)

Prophylactic cranial irradiation (PCI) is a preventative whole-brain irradiation technique used to reduce the incidence of brain metastasis and improve overall survival in select patients with small cell lung cancer and acute lymphoblastic leukemia. A population of breast cancer patients – stage IV, HER2+ or triple-negative – has emerged as having a high risk of developing brain metastases. Because only 10-20% of breast cancer patients diagnosed with brain metastases survive longer than one year, in this high-risk population the benefit of PCI – potential for reduced incidence of brain metastasis and improved overall survival – may outweigh the risks – radiation toxicity. The objective of ...


Gating Mechanisms Of The Canonical Trp Channel Isoform Trpc4, Dhananjay P. Thakur Aug 2015

Gating Mechanisms Of The Canonical Trp Channel Isoform Trpc4, Dhananjay P. Thakur

UT GSBS Dissertations and Theses (Open Access)

Non-selective cation channels formed by Transient Receptor Potential Canonical (TRPC) proteins play important roles in regulatory and pathophysiological processes. These channels are known to be activated downstream from phospholipase C (PLC) signaling. However, the mechanism by which the PLC pathway activates TRPC4/C5 remains unclear. Uniquely, TRPC4 is maximally activated only when two separate G protein pathways, Gq/11 and Gi/o, are co-stimulated, making it a coincidence detector of Gq/11- and Gi/o -coupled receptor activation. Using HEK293 cells co-expressing mouse TRPC4β and selected G protein-coupled receptors, I observed that coincident stimulation of G ...


Computational Modeling Of Rna-Small Molecule And Rna-Protein Interactions, Lu Chen Aug 2015

Computational Modeling Of Rna-Small Molecule And Rna-Protein Interactions, Lu Chen

UT GSBS Dissertations and Theses (Open Access)

The past decade has witnessed an era of RNA biology; despite the considerable discoveries nowadays, challenges still remain when one aims to screen RNA-interacting small molecule or RNA-interacting protein. These challenges imply an immediate need for cost-efficient while predictive computational tools capable of generating insightful hypotheses to discover novel RNA-interacting small molecule or RNA-interacting protein. Thus, we implemented novel computational models in this dissertation to predict RNA-ligand interactions (Chapter 1) and RNA-protein interactions (Chapter 2).

Targeting RNA has not garnered comparable interest as protein, and is restricted by lack of computational tools for structure-based drug design. To test the potential ...


Investigating The Interaction Of Aurka And Ube2c In Colorectal Cancer Cells, Apurva M. Hegde Aug 2015

Investigating The Interaction Of Aurka And Ube2c In Colorectal Cancer Cells, Apurva M. Hegde

UT GSBS Dissertations and Theses (Open Access)

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the US. Among the many genomic aberrations previously implicated in colorectal cancer, recurrent amplification of chromosome 20q is frequently associated with liver metastasis. Previous research in our lab identified a gene signature on chromosome 20q associated with colorectal cancer progression. In this study, one of the genes in the signature, the ubiquitin conjugating enzyme UBE2C, was identified through preliminary bioinformatics analysis as a candidate for further examination of its role in CRC progression. Co-expression analysis of UBE2C in tumor-normal datasets from the public database Oncomine revealed all the ...


Histone H3 K4 Methylation Regulates The Spindle Assembly Checkpoint Through Direct Binding Of Multiple Checkpoint Components And Cdc20, Andria C. Schibler Aug 2015

Histone H3 K4 Methylation Regulates The Spindle Assembly Checkpoint Through Direct Binding Of Multiple Checkpoint Components And Cdc20, Andria C. Schibler

UT GSBS Dissertations and Theses (Open Access)

Histone H3K4 methylation is conserved across species and is associated with active transcription. By using Saccharomyces cerevisiae, we found histone H3K4 methylation has a previously unknown role in regulating mitosis through the Spindle Assembly Checkpoint. The Spindle Assembly Checkpoint ensures duplicated chromosomes are segregated correctly and each daughter cell receives one full copy of the genome. Our data show SET1 mutants and histone H3K4 mutants display a resistance to the mitotic poison, benomyl. Moreover methylated histone H3 directly binds to Spindle Assembly Checkpoint proteins Bub3 and Mad2 as well as the activator of the Anaphase Promoting Complex (APC) protein Cdc20 ...


Direct Regulation Of Apoptosis By Linear Ubiqutin Chain Assembly Complex (Lubac) And Feedback Regulation Of Lubac Function By Caspases, Donghyun Joo Aug 2015

Direct Regulation Of Apoptosis By Linear Ubiqutin Chain Assembly Complex (Lubac) And Feedback Regulation Of Lubac Function By Caspases, Donghyun Joo

UT GSBS Dissertations and Theses (Open Access)

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine that plays a role in various cellular processes such as proliferation, differentiation (mainly through NF-κB signaling) and death (via apoptosis signaling). Recently, linear ubiquitination by LUBAC (linear ubiquitin chain assembly complex) was reported to have a regulatory function in TNF-α mediated NF-κB activation. Although LUBAC is suggested to control not only NF-kB signaling but also the apoptosis pathway, the precise mechanism of apoptosis regulation remains unknown. Moreover, NF-κB and apoptosis pathways have opposed but fundamental functions for various cellular processes. Although these two pathways actively interplay to balance the death and survival, the ...


Investigation Of The Role Of The Scaffold Protein Shc In Erk Signaling, Kin Man Suen May 2015

Investigation Of The Role Of The Scaffold Protein Shc In Erk Signaling, Kin Man Suen

UT GSBS Dissertations and Theses (Open Access)

Cells respond to environmental changes by converting extracellular signals into intracellular events. Scaffolding proteins play important roles in generating specificity in intracellular signaling through the combinatorial use of protein domains and posttranslational modifications. Using the scaffold Shc (Src-homology collagen-like) as a model system, we explored novel mechanisms whereby this class of protein shapes signaling output. In the present work, we focused on the role of Shc in the MAP kinase Erk signaling both prior to and post-growth factor stimulation. Prior to growth factor stimulation, we found Erk to be a direct interacting partner of Shc. The two proteins associate through ...


The Effect Of Activation Induced Cytidine Deaminase Phosphorylation And Herpes Virus Uracil Dna Glycosylase On Antibody Diversification, Marc Macaluso May 2015

The Effect Of Activation Induced Cytidine Deaminase Phosphorylation And Herpes Virus Uracil Dna Glycosylase On Antibody Diversification, Marc Macaluso

UT GSBS Dissertations and Theses (Open Access)

Activation-induced cytidine deaminase (AID) is a mutagenic enzyme that is expressed in mammalian B-cells and initiates the antibody diversification processes of somatic hypermuntation (SHM) and isotype class switch recombination (CSR). AID is targeted to the immunoglobulin gene locus where it deaminates cytosines to generate uracil residues in DNA. This generates guanine-uracil (U:G) mismatch lesion which are recognized by uracil DNA glycosylase (UNG), a DNA repair enzyme that removes uracil from DNA and triggers downstream repair of the lesion. While UNG is a ubiquitously expressed DNA repair enzyme, its recognition and removal of AID introduced uracils is essential in both ...


The Structural Mechanism Of Allosteric Modulation Of The Nmda Receptor: A Balance Of Tensions, Rita E. Sirrieh May 2015

The Structural Mechanism Of Allosteric Modulation Of The Nmda Receptor: A Balance Of Tensions, Rita E. Sirrieh

UT GSBS Dissertations and Theses (Open Access)

N-methyl-D-aspartate (NMDA) receptors are one of the three main types of ionotropic glutamate receptors in the central nervous system. NMDA receptors mediate the rapid excitatory neurotransmission that underlies learning and memory formation. Conversely, NMDA receptors are implicated in a variety of neurological disorders. Studies targeting the mechanism of allosteric modulation, such as this study, hope to contribute to the understanding of how NMDA receptors are modulated to allow for better drug development.

NMDA receptors are obligate heterotetramers, typically composed of glycine-binding GluN1 subunits and glutamate-binding GluN2 subunits. The GluN2 subunits can be one of four subtypes (A-D). Each subunit is ...


Regulation Of Cell Adhesion By The Ferm Proteins, Ptpn14 And Merlin, Patty Dimarco Hewitt May 2015

Regulation Of Cell Adhesion By The Ferm Proteins, Ptpn14 And Merlin, Patty Dimarco Hewitt

UT GSBS Dissertations and Theses (Open Access)

Cell-cell adhesion is critical for the control of tissue organization and homeostasis. A family of proteins that regulate cell-cell adhesions is the FERM (4.1 protein, Ezrin, Radixin, Moesin) domain-containing proteins.One FERM domain protein, the non-receptor tyrosine phosphatase PTPN14, is mutated or deleted in several human cancers suggesting that it may be involved in tumor development and/or progression. Additionally, the loss of the FERM domain protein Merlin is associated with tumor development and metastasis.Both PTPN14 and Merlin have been shown to localize and possibly regulate adherens junction (AJ) functions. This work sought to determine ...


Measuring Single Cell Responses To Lapatinib In A Heterogeneous Population, Preety Priya May 2015

Measuring Single Cell Responses To Lapatinib In A Heterogeneous Population, Preety Priya

UT GSBS Dissertations and Theses (Open Access)

Cancer is notonedisease butasaga of diseases and is the outcome of disturbed homeostasis in the normal cells due to the deregulation of its genetic makeup. With advent of technologies thatallowdetailed molecular characterizationoftumors, targeted therapies have emerged as a more promising and specific mode of treatment. However, a major challenge with targeted therapy is the acquired resistance in the cancer cells to these therapies, quite often very rapidly in the course of a few months. One of the major targets in cancer has been the EGFR/ErbB2 network in breast and other cancer types. Prior work from our lab and others ...


Investigating The Roles Of P63 And P73 Isoforms To Therapeutically Treat P53-Altered Cancers, Avinashnarayan Venkatanarayan May 2015

Investigating The Roles Of P63 And P73 Isoforms To Therapeutically Treat P53-Altered Cancers, Avinashnarayan Venkatanarayan

UT GSBS Dissertations and Theses (Open Access)

Investigating the roles of p63 & p73 isoforms to therapeutically treat

p53-altered cancers

Avinashnarayan Venkatanarayan, M.S.

Supervisory Professor: Elsa R. Flores, Ph.D.

The TP53 tumor suppressor is mutated in approximately 50% of human cancers rendering cancer therapies ineffective. p53 reactivation suppresses tumor formation in mice. However, this strategy has proven difficult to implement therapeutically. An alternate approach to overcome p53 loss is to manipulate the p53-family members, p63 and p73, which interact and share structural similarities to p53. p63 and p73, unlike p53 are less frequently mutated and have two major isoforms with distinct functions which makes them ...


Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh May 2015

Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh

UT GSBS Dissertations and Theses (Open Access)

In mammalian cells, DNA polymerase θ (POLQ) is an unusual specialized DNA polymerase whose in vivo function is under active investigation. The protein is comprised of an N-terminal helicase-like domain, a C-terminal DNA polymerase domain, and a large central domain that spans between the two. This arrangement is also found in the Drosophila Mus308 protein, which helps confer resistance to DNA interstrand crosslinking agents. Homologs of POLQ and Mus308 are found in eukaryotes, including plants, but a comparison of phenotypes suggests that not all of these genes are functional orthologs. Flies with defective Mus308 are sensitive to DNA interstrand crosslinking ...


Developmental Origins Of Renal Connecting Tubule And Collecting Duct: Role Of Aqp2+ Progenitor Cells, Lihe Chen May 2015

Developmental Origins Of Renal Connecting Tubule And Collecting Duct: Role Of Aqp2+ Progenitor Cells, Lihe Chen

UT GSBS Dissertations and Theses (Open Access)

The connecting tubule interconnects the nephron and collecting duct, which arise from kidney mesenchyme and the ureteric bud, respectively, to generate the functional tubular networks. The collecting duct is comprised of principal cells and intercalated cells, which bear different molecular signatures and regulate sodium/water and acid/base balance, respectively. The progenitor cells of the connecting tubule and the collecting duct remain virtually unknown.

We generated two Aqp2 lineage tracing mouse models. In these models, Aqp2Cre transgene drives Cre expression by the Aqp2 promoter to exclusively either inactivate histone H3 K79 methyltransferase Dot1l (Dot1lf/f Aqp2Cre) or activate RFP ...


Selection Methods For Genetically-Modified T Cells: In Support Of Translational Therapy, David Rushworth May 2015

Selection Methods For Genetically-Modified T Cells: In Support Of Translational Therapy, David Rushworth

UT GSBS Dissertations and Theses (Open Access)

T cells are blood cells which organize the immune system of the host. These cells are necessary for the host to respond appropriately to threats from foreign organisms and cancerous growth. However, in the case of certain infections and cancer, T cells are unable to respond appropriately to a threat and establish immunity. This leads to disease when the infection or cancer is not sufficiently eliminated. On the other hand, T cells can lack tolerance for healthy tissue and perceive healthy tissue as infected. The ensuing over-reactive immune response also leads to disease. A delicate balance must exist between immunity ...