Medical Molecular Biology Commons^™

Genetic Association Studies Of Copy-Number Variation: Should Assignment Of Copy Number States Precede Testing?, Patrick Breheny, Prabhakar Chalise, Anthony Batzler, Liewei Wang, Brooke L. Fridley

Biostatistics Faculty Publications

Recently, structural variation in the genome has been implicated in many complex diseases. Using genomewide single nucleotide polymorphism (SNP) arrays, researchers are able to investigate the impact not only of SNP variation, but also of copy-number variants (CNVs) on the phenotype. The most common analytic approach involves estimating, at the level of the individual genome, the underlying number of copies present at each location. Once this is completed, tests are performed to determine the association between copy number state and phenotype. An alternative approach is to carry out association testing first, between phenotype and raw intensities from the SNP array …

Targeting Apoptosis For Optical Imaging Of Infection, Mathew L Thakur, Kaijun Zhang, Bishnuhari Paudyal, Devadhas Devakumar, Maria Y Covarrubias, Changpo Cheng, Brian D Gray, Eric Wickstrom, Koon Y Pak

Department of Radiology Faculty Papers

PURPOSE: Infection is ubiquitous and a major cause of morbidity and mortality. The most reliable method for localizing infection requires radiolabeling autologous white blood cells ex vivo. A compound that can be injected directly into a patient and can selectively image infectious foci will eliminate the drawbacks. The resolution of infection is associated with neutrophil apoptosis and necrosis presenting phosphatidylserine (PS) on the neutrophil outer leaflet. Targeting PS with intravenous administration of a PS-specific, near-infrared (NIR) fluorophore will permit localization of infectious foci by optical imaging.

METHODS: Bacterial infection and sterile inflammation were induced in separate groups (n = 5) …

Structural Insights Into Initial And Intermediate Steps Of The Ribosome-Recycling Process, Takeshi Yokoyama, Tanvir R. Shaikh, Nobuhiro Iwakura, Hideko Kaji, Akira Kaji, Rajendra K. Agrawal

Department of Biochemistry and Molecular Biology Faculty Papers

The ribosome recycling factor (RRF) and elongation factor G (EF-G) disassemble the 70S post-termination complex (PoTC) into mRNA, tRNA, and two ribosomal subunits. We have determined cryo-EM structures of the PoTC•RRF complex, with and without EF-G. We find that domain II of RRF initially interacts with universally conserved residues of the 23S rRNA helices 43 and 95, and protein L11 within the 50S ribosomal subunit. Upon EF-G binding, both RRF and tRNA are driven toward the tRNA-exit (E) site, with a large rotational movement of domain II of RRF toward the 30S ribosomal subunit. During this intermediate step of the …

Pathobiological Implications Of The Expression Of Egfr, Pakt, Nf-Κb And Mic-1 In Prostate Cancer Stem Cells And Their Progenies., Murielle Mimeault, Sonny L. Johansson, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The progression of prostate cancers (PCs) to locally invasive, androgen-independent and metastatic disease states is generally associated with treatment resistance and disease relapse. The present study was undertaken to establish the possibility of using a combination of specific oncogenic products, including epidermal growth factor receptor (EGFR), pAkt, nuclear factor-kappaB (NF-κB) and macrophage inhibitory cytokine-1 (MIC-1) as biomarkers and therapeutic targets for optimizing the management of patients with localized PC at earlier disease stages. The immunohistochemical and immunofluorescence data have revealed that the expression levels of EGFR, Ser(473)-pAkt, NF-κB p65 and MIC-1 proteins were significantly enhanced in the same subset of …

Regulation Of A Duplicated Locus: Drosophila Sloppy Paired Is Replete With Functionally Overlapping Enhancers., Miki Fujioka, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

In order to investigate regulation and redundancy within the sloppy paired (slp) locus, we analyzed 30 kilobases of DNA encompassing the tandem, coordinately regulated slp1 and slp2 transcription units. We found a remarkable array of stripe enhancers with overlapping activities surrounding the slp1 transcription unit, and, unexpectedly, glial cell enhancers surrounding slp2. The slp stripe regulatory region generates 7 stripes at blastoderm, and later 14 stripes that persist throughout embryogenesis. Phylogenetic analysis among drosophilids suggests that the multiplicity of stripe enhancers did not evolve through recent duplication. Most of the direct integration among cis-regulatory modules appears to be simply additive, …

Mir-25 Targets Tnf-Related Apoptosis Inducing Ligand (Trail) Death Receptor-4 And Promotes Apoptosis Resistance In Cholangiocarcinoma., Nataliya Razumilava, Steve F. Bronk, Rory L. Smoot, Christian D. Fingas, Nathan W. Werneburg, Lewis R. Roberts, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

It has been established that microRNA expression and function contribute to phenotypic features of malignant cells, including resistance to apoptosis. Although targets and functional roles for a number of microRNAs have been described in cholangiocarcinoma, many additional microRNAs dysregulated in this tumor have not been assigned functional roles. In this study, we identify elevated miR-25 expression in malignant cholangiocarcinoma cell lines as well as patient samples. In cultured cells, treatment with the Smoothened inhibitor, cyclopamine, reduced miR-25 expression, suggesting Hedgehog signaling stimulates miR-25 production. Functionally, miR-25 was shown to protect cells against TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Correspondingly, antagonism of …

Enteric Alpha Defensins In Norm And Pathology., Nikolai A Lisitsyn, Yulia A Bukurova, Inna G Nikitina, George S Krasnov, Yuri Sykulev, Sergey F Beresten

Kimmel Cancer Center Faculty Papers

ABSTRACT: Microbes living in the mammalian gut exist in constant contact with immunity system that prevents infection and maintains homeostasis. Enteric alpha defensins play an important role in regulation of bacterial colonization of the gut, as well as in activation of pro- and anti-inflammatory responses of the adaptive immune system cells in lamina propria. This review summarizes currently available data on functions of mammalian enteric alpha defensins in the immune defense and changes in their secretion in intestinal inflammatory diseases and cancer.

The Use Of Cerium Oxide And Curcumin Nanoparticles As Therapeutic Agents For The Treatment Of Ventricular Hypertrophy Following Pulmonary Arterial Hypertension, Madhukar Babu Kolli

Theses, Dissertations and Capstones

Pulmonary arterial hypertension (PAH) is a progressive and fatal disease characterized by inflammation, increased pulmonary vascular resistance, right ventricular failure and premature death. Monocrotaline (MCT) has been used to induce PAH in laboratory rats. Previous in vitro and in vivo work suggested that cerium oxide (CeO2)-and curcumin nanoparticles exhibit anti-inflammatory activity; however, it is unknown if these materials are effective for the treatment of PAH induced cardiac hypertrophy. To determine the efficacy of CeO2 nanoparticle treatment in preventing MCT-induced RV hypertrophy, male Sprague Dawley rats were divided into one of three groups (control, MCT, or MCT + CeO2 nanoparticle, n=6/group). …

Early Events In Herpes Simplex Virus Lifecycle With Implications For An Infection Of Lifetime, Sarah Salameh '12, Urmi Sheth '12, Deepak Shukla

Student Publications & Research

Affecting a large percentage of human population herpes simplex virus (HSV) types -1 and -2 mainly cause oral, ocular, and genital diseases. Infection begins with viral entry into a host cell, which may be preceded by viral “surfing” along filopodia. Viral glycoproteins then bind to one or more of several cell surface receptors, such as herpesvirus entry mediator (HVEM), nectin-1, 3-O sulfated heparan sulfate (3-OS HS), paired immunoglobulin-like receptor, and non-muscle myosin-IIA. At least five viral envelope glycoproteins participate in entry and these include gB, gC, gD and gH-gL. Post-entry, these glycoproteins may also facilitate cell-to-cell spread of the virus, …

Activation Of Protein Phosphatase 2c By Ceramide And Essential Role Of Acid Sphingomyelinase In Interleukin-6 Synthesis, David Mark Perry

MUSC Theses and Dissertations

Since their discovery over a century ago, sphingolipids have riddled and fascinated the scientific community with benchmarks of progress including the identification of the enzymatic defects in the lysosomal storage diseases and the discovery of their involvement in cellular processes. Excluding sphingosine-1-phosphate with its associated G-protein coupled receptors, a staggering gap still persists in our understanding of the mechanisms related to the functions of the sphingolipids, ceramide and sphingosine. Moreover, in spite of the impressive amount of literature implicating ceramide in biological processes, precise and well-documented roles in biology for specific ceramide-producing enzymes are surprisingly rare. To further investigate the …

The Epigenetic Regulation Of Cubilin And The Physiological Role Of This Receptor In Maintaining The Homeostasis Of Serum Albumin And Hdl, Sayed Obaidullah Aseem

MUSC Theses and Dissertations

Cubilin is an endocytic receptor capable of mediating the endocytosis of multiple ligands including High Density Lipoprotein apolipoprotein A-I (apoA-1) and albumin. It is highly expressed on the epithelium of intestinal villi and renal proximal tubules. In the kidney, endocytosis mediated by cubilin and its co-receptor megalin is the principal mechanism for proximal tubule reabsorption of filtered proteins, such as albumin and apoA-1. Yet, the consequences of cubilin deficiency on the blood levels of albumin and apoA-1 have not been studied. Furthermore, cubilin is downregulated in chronic diseases such as diabetes. However, little is known about the regulation of cubilin …

Signaling Mechanisms Involved In The Generation Of Human Peripheral Itregs, Mary Catherine Reneer

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Maintaining balance in the human immune system is critical for the body’s ability to discriminate between foreign and self-antigens. This balance is achieved, in part, by a subpopulation of T cells known as induced regulatory T cells (iTregs). Dysregulation of this population may contribute to the onset and progression of cancer, chronic inflammation and autoimmune diseases. Therefore, manipulation of iTreg development holds promising therapeutic potential; however, studying this vital population has proven difficult due to low numbers, heterogeneous cell populations, substantial phenotypic differences between mouse and human cells, and the high plasticity seen in iTregs. These current limitations have prevented …

Prion Characterization Using Cell Based Approaches, Vadim Khaychuk

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Prions are the causative agents of a group of lethal, neurodegenerative conditions that include sheep scrapie, bovine spongiform encephalopathy (BSE), and human Creutzfeldt-Jakob disease (CJD). Prions are derived from the conversion of a normal, primarily alpha-helical, cellular prion protein (PrP^C), to an infectious, beta sheet-rich conformer (PrP^Sc). Many unresolved issues surround the process of PrP conversion, and we know very little about cellular responses to these unique pathogens. Our lack of knowledge relates, in part, to the difficulty of infecting cells in vitro with prions. While expression of PrP^C is an absolute requirement for prion …

Relationships Between Telomeric Sequences And Structures, Dna Replication, And The Function Of The Werner Syndrome Protein, Deanna Edwards

Theses and Dissertations--Toxicology and Cancer Biology

All human chromosomes end with protective structures called telomeres, which consist of thousands of double-stranded TTAGGG repeats and end in a 3’ guanine-rich overhang. These structures shorten normally during each round of replication, and extremely short telomeres along with telomere dysfunction are thought to contribute to the development of aging and cancer. Although many proteins have roles in telomere maintenance, WRN, which is a 3’ to 5’ helicase that is deficient in the premature aging disorder Werner’s syndrome, has been proposed to play multiple roles at telomeres. In this study, I focus on the effect of telomeric sequences and/or structures …

Proteasome Regulation Of Caspase-8: Significance In Cancer, Michael Vincent Fiandalo

Theses and Dissertations--Molecular and Cellular Biochemistry

Anti-tumor therapeutic strategies based on combinations of chemotherapeutic agents with a death inducing ligand such as TNF-α Related Apoptosis Inducing Ligand (TRAIL), are directed towards selective and effective cancer cell apoptosis and enhanced therapeutic response. We previously demonstrated that proteasome inhibition sensitizes TRAIL resistant prostate cancer cells to TRAIL-mediated apoptosis via stabilization of the active p18 subunit of initiator caspase-8. The present study investigated the functional link between caspase-8 and the proteasome, by analyzing the impact of caspase-8 ubiquitination and proteasomal degradation on the outcomes of the extrinsic apoptosis pathway in cancer cells. Caspase-8 ubiquitination status was assessed by polyubiquitin …

A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel

CMC Senior Theses

The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …

Determining Efficacy Of Breast Cancer Therapy By Pet Imaging Of Her2 Mrna, Bishnuhari Paudyal, Kaijun Zhang, Changpo Chen, Neil Mehta, Eric Wickstrom, Brian Gray, Jeffrey Mattis, Koon Pak, Mathew L Thakur

Department of Radiology Faculty Papers

No abstract provided.

Optical Imaging For Determination Of Apoptosis Medicated Therapeutic Efficacy, Kaijun Zhang, Bishnuhari Paudyal, Neil Mehta, Brian Gray, Koon Y. Pak, Eric Wickstrom, Mathew L Thakur

Department of Radiology Faculty Papers

No abstract provided.

Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Evidence from multiple animal models demonstrates that testosterone plays a crucial role in the progression of symptoms in spinal and bulbar muscular atrophy (SBMA), a condition that results in neurodegeneration and muscle atrophy in affected men. Mice bearing a transgene encoding a human androgen receptor (AR) that contains a stretch of 112 glutamines (expanded polyglutamine tract; AR112Q mice) reproduce several aspects of the human disease. We treated transgenic male AR112Q mice with testosterone for 6 months. Surprisingly, testosterone treatment of AR112Q males did not exacerbate the disease. Although transgenic AR112Q males exhibited functional deficits when compared with non-transgenics, long-term testosterone …

Mitochondrial Lysyl-Trna Synthetase Independent Import Of Trna Lysine Into Yeast Mitochondria., Naresh Babu V Sepuri, Madhavi Gorla, Michael P King

Department of Biochemistry and Molecular Biology Faculty Papers

Aminoacyl tRNA synthetases play a central role in protein synthesis by charging tRNAs with amino acids. Yeast mitochondrial lysyl tRNA synthetase (Msk1), in addition to the aminoacylation of mitochondrial tRNA, also functions as a chaperone to facilitate the import of cytosolic lysyl tRNA. In this report, we show that human mitochondrial Kars (lysyl tRNA synthetase) can complement the growth defect associated with the loss of yeast Msk1 and can additionally facilitate the in vitro import of tRNA into mitochondria. Surprisingly, the import of lysyl tRNA can occur independent of Msk1 in vivo. This suggests that an alternative mechanism is present …