Molecular Biology Commons^™

Analyzing The Interactions Between Xenopus Tropicalis Mc2r, Mc5r, And The Mraps: Modeling The Regulation Of Frog Interrenal Cells, Yesenia Garcia

Electronic Theses and Dissertations

The role of Melanocortin 2 Receptor (MC2R) in adrenal/interrenal glucocorticoid secretion has been well documented in many organisms. Studies in mammals have shown that in the adrenal gland two melanocortin receptors and two melanocortin receptor accessory proteins are expressed: MC2R, MC5R, MRAP, and MRAP2. The MRAPs have an opposite effect on the cell surface expression of MC2R and MC5R. In mammals, MRAP aids MC2R but inhibits MC5R cell surface expression. This thesis aims to explore the functional relationship between MC2R, MC5R, MRAP, and MRAP2 in Xenopus tropicalis to determine if the MRAPs have a similar effect on amphibian MC2R and …

Cross-Disciplinary Sciences At Gettysburg College: Second Annual Poster Presentation, X-Sig

Student Publications

This booklet includes Biology student presentations by: Taylor Bury, Abigail Dworkin-Brodsky, Mary Pearce, Jasper Leavitt, Morgan Panzer, Ellen Petley, Kalli Qutub, Taylor Randell, Samantha Eck, Lana McDowell, Jenn Soroka, Celina Harris, Natalie Tanke, Alexandra Turano, and Caroline Garliss.

This booklet includes Biochemistry & Molecular Biology student presentations by: Matthew Dunworth, Andrew Sydenstricker, Brianne Tomko, Albert Vill, Warren Campbell, David Van Doren, Kevin Mrugalski, Stacey Heaver, Alecia Achimovich, and Katherine Boas.

This booklet includes Chemistry student presentations by: Kristen Baker, Laura Lee, Kathryn Fodale, Daniel Ruff, Michael Counihan, Ida DiMucci, Joshua Sgroi, Celina Harris, and Natalie Tanke.

This booklet include Health …

Development Of A Bead-Based Suspension Array For Detection And Differentiation Of Salmonella Spp. In Poultry, Muhsin Aydin

Student Theses and Dissertations

Salmonella is the leading cause of foodborne illnesses in the United States. Recent outbreaks associated with Salmonella-contaminated foods and related economic loss show the need for effective strategies to control Salmonella in foods. Because of deleterious effects of Salmonella on public health and economy, it is highly desirable to develop a detection method that can identify Salmonella in food with good sensitivity and rapidity. The goal of this study was to develop a sensitive, rapid, and specific bead-based multiplexing array system to identify Salmonella at the serotype level as a method of effectively monitoring food samples for the presence of …

Analysis Of Differential Mrna And Mirna Expression In An Alzheimer’S Disease Mouse Model, Amanda Hazy, Matthew Dalton

Other Undergraduate Scholarship

Research has shown that changes in gene expression play a critical role in the development of Alzheimer’s Disease (AD). Our project will evaluate genome-wide RNA expression patterns from brain and blood in an AD mouse model. This analysis will provide insight regarding the mechanisms of AD pathology as well as determine a possible diagnostic tool utilizing RNA expression patterns found in the blood as biomarkers for AD.

Dietary Carbohydrates Influence The Structure And Function Of The Intestinal Alpha-Glucosidases, Mohammad Chegeni

Open Access Dissertations

As the primary products of starch digestion by pancreatic α-amylase, maltooligosaccharides (including maltose) are the main substrates for the α-glucosidases at the intestinal brush border. Here, maltose was shown to induce the formation of a higher molecular weight (HMW) sucrase-isomaltase (SI) species in Caco-2 cells that sorts more quickly to the enterocyte surface to act as a digestive enzyme. As this finding suggested a maltose sensing ability of small intestinal enterocytes, molecular mechanisms associated with the maturation and trafficking of HMW SI were further investigated. A pulse-chase experiment using [ ³⁵S]-methionine revealed a higher rate of early trafficking and …

Effects Of Altered Expression Of The Sumo Conjugating Enzyme, Ubc9 On Mitosis, Meiosis And Conjugation In Tetrahymena Thermophila, Qianyi Yang

Open Access Dissertations

SUMOylation is a critical posttranslational modification in eukaryotic species. Ubc9p is the E2-conjugating enzyme for SUMOylation and consequently it influences multiple cellular pathways. Nuclear proteins are common targets of SUMOylation and regulate nuclear events such as transcription, DNA repair and mitosis. The segregation of the Tetrahymena thermophila genome into two different nuclear compartments provides an unusual context for the analysis of SUMOylation. Each cell contains a transcriptionally silent, diploid germ line micronucleus (MIC) that divides by mitosis and a polyploid transcriptionally active somatic macronucleus (MAC) that divides by an amitotic mechanism. With the long-term goal to exploit these opportunities we …

New Strategies To Reveal Protein Candidates In Protein-Protein Interactome Study, Meng-Chieh Chen

Open Access Theses

Comprehensive protein-protein interaction network analysis can help reveal protein functions in a system-wide manner. A reliable knowledgebase of interaction networks is not only important for selecting the candidates for drug therapies, but also for evaluating the disease risk. In current interaction databases, 322579 interactions comprised of 56460 proteins have been reported (statistical analysis from APID: Agile Protein Interaction DataAnalyzer; http://bioinfow.dep.usal.es/apid/index.htm). The huge datasets are contributed mainly by yeast -two -hybrid (Y2H) screening and affinity-purification followed by mass spectrometry (AP-MS). High false positive rates and failing to cover certain interaction categories are the limitations of these two methods. Here, we developed …

Host Cell Death In Legionella Pneumophila Pathogenesis And Immunity, Wenhan Zhu

Open Access Dissertations

Legionella pneumophila is an intracellular pathogen that causes a severe, atypical pneumonia termed Legionnaires' disease. Upon entering the host cell, L. pneumophila resides in a membrane-bound vacuole, in which the bacterium evades lysosomal fusion and replicates. The establishment of the vacuole requires the Dot/Icm (Defect in organelle trafficking/ intracellular multiplication) transport system, which translocates a large number of substrates into host cells to re-orchestrate various cellular processes, such as intracellular trafficking, protein synthesis and host cell death pathways. Therefore, a key step in understanding the biology of Legionella is to dissect the mechanisms of action of the Dot/Icm substrates. By …

Associated Behavioral, Genetic, And Gene Expression Variation With Alternative Life History Tactics In Salmonid Fishes, Ashley Chin-Baarstad

Open Access Dissertations

Individual differences in behavior can have potential fitness consequences and often reflect underlying genetic variation. My research focuses on three objectives related to individual level variation: 1) evaluating the innate behavioral variation within and between individuals, families, and progeny of different life-history types across time; 2) testing for differences in gene expression within the brain associated with this behavioral variation; and 3) using genetic polymorphisms to test for associations with ecotype, as well as population structure, in polymorphic populations. First, we evaluated the variation in a suite of ecologically relevant behaviors across time in juvenile progeny produced from crosses within …

The Non-Canonical Hydroxylase Structure Of Yfcm Reveals A Metal Ion-Coordination Motif Required For Ef-P Hydroxylation, Kan Kobayashi, Assaf Katz, Andrei Rajkovic, Ryohei Ishii, Owen E. Branson, Michael A. Freitas, Ryuichiro Ishitani, Michael Ibba, Osamu Nureki

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

EF-P is a bacterial tRNA-mimic protein, which accelerates the ribosome-catalyzed polymerization of poly-prolines. In Escherichia coli, EF-P is post-translationally modified on a conserved lysine residue. The post-translational modification is performed in a two-step reaction involving the addition of a β-lysine moiety and the subsequent hydroxylation, catalyzed by PoxA and YfcM, respectively. The β-lysine moiety was previously shown to enhance the rate of poly-proline synthesis, but the role of the hydroxylation is poorly understood. We solved the crystal structure of YfcM and performed functional analyses to determine the hydroxylation mechanism. In addition, YfcM appears to be structurally distinct from any …

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster, Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty, Staff and Students Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

Identification And Characterization Of A Functional L-Gulono-1,4-Lactone Oxidase In Arabidopsis Thaliana, Siddique Aboobucker

Student Theses and Dissertations

Vitamin C (ascorbate, AsA) is essential for plant and animal health. We cannot synthesize AsA on our own and therefore we must consume it from fruits and vegetables. Ascorbate plays multiple roles in plant physiology, and increasing AsA content in plants remains challenging. There are four biosynthetic AsA pathways in plants: the D-mannose/L-galactose, L-gulose, D-galacturonate, and myo-inositol routes. The AsA metabolic network is not completely understood. The inositol pathway has four enzyme-catalyzed steps, and our group has made significant progress on characterizing the first three enzymes. This work focuses on L-gulono-1,4-lactone oxidase (GulLO), the last enzyme in the inositol pathway …

Mechanisms And Molecular Biology Of Major Tumor Suppressors, Brienne E. Engel

USF Tampa Graduate Theses and Dissertations

This dissertation is devoted to the study of the molecular biology of major tumor suppressors, defined as those that prevent the cellular processes identified as the hallmarks of cancer. Specifically, the major tumor suppressors pRb and STK11 are explored in the context of osteosarcoma and lung cancer, respectively.

RB1 was the first tumor suppressor gene discovered. Over four decades of work have revealed that the Rb protein (pRb) is a master regulator of biological pathways influencing virtually every aspect of intrinsic cell fate including cell growth, cell-cycle checkpoints, differentiation, senescence, self-renewal, replication, genomic stability and apoptosis. While these many processes …

Role And Regulation Of Snon/Skil And Plscr1 Located At 3q26.2 And 3q23, Respectively, In Ovarian Cancer Pathophysiology, Madhav Karthik Kodigepalli

USF Tampa Graduate Theses and Dissertations

Ovarian cancer is one of the most common causes of gynecological cancer related deaths in women. In 2014, the estimated number of deaths due to ovarian cancer is 14,270 with occurrence of over 22, 240 new cases (National Cancer Institute, http://seer.cancer.gov/statfacts/html/ovary.html). Despite improvement in treatment strategies, the 5-year survival rate is still below 50% mainly due to chemoresistance and relapse. Amplification of chromosomal region 3q26 is a common characteristic in various epithelial cancers including ovarian cancer. This region harbors various oncogenes including the TGFβ signaling mediators EVI1 and SnoN/SkiL, PKCι and PIK3CA amplified at 3q26.2 and 3q26.3, respectively, in ovarian …

Eukaryotic Gene Expression Patterns Of Microorganisms In The Amazon River Plume Parallel The Biogeochemistry Of Plume Waters, Brian L. Zielinski

USF Tampa Graduate Theses and Dissertations

Unraveling the microbiological processes that occur as water travels from a river's mouth into the ocean is critical to understanding the role of river plumes in global biogeochemical cycles. Metranscriptomics, the gene expression of a whole community of organisms, was utilized to examine six stations along the Amazon River Plume (ARP) in 2010 to test thehypothesis that there were measurable differences in gene expression for key biogeochemical genes along the ARP. This body of work focuses on methods developed to identify which genes are biogeochemically important for a particular environment along extreme salinity, nutrient and community gradients in the ARP, …

Mistranslation Of The Genetic Code, Adil Moghal, Kyle Mohler, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

During mRNA decoding at the ribosome, deviations from stringent codon identity, or “mistranslation,” are generally deleterious and infrequent. Observations of organisms that decode some codons ambiguously, and the discovery of a compensatory increase in mistranslation frequency to combat environmental stress have changed the way we view “errors” in decoding. Modern tools for the study of the frequency and phenotypic effects of mistranslation can provide quantitative and sensitive measurements of decoding errors that were previously inaccessible. Mistranslation with non‐protein amino acids, in particular, is an enticing prospect for new drug therapies and the study of molecular evolution.

Relaxed Substrate Specificity Leads To Extensive Trna Mischarging By Streptococcus Pneumoniae Class I And Class Ii Aminoacyl-Trna Synthetases, Jennifer Shepherd, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases provide the first step in protein synthesis quality control by discriminating cognate from noncognate amino acid and tRNA substrates. While substrate specificity is enhanced in many instances by cis- and trans-editing pathways, it has been revealed that in organisms such as Streptococcus pneumoniae some aminoacyl-tRNA synthetases display significant tRNA mischarging activity. To investigate the extent of tRNA mischarging in this pathogen, the aminoacylation profiles of class I isoleucyl-tRNA synthetase (IleRS) and class II lysyl-tRNA synthetase (LysRS) were determined. Pneumococcal IleRS mischarged tRNA^Ile with both Val, as demonstrated in other bacteria, and Leu in a tRNA sequence-dependent …

Role Of Vitamin D3 In Modulation Of Δnp63Α Expression During Uvb Induced Tumor Formation In Skh-1 Mice, Natasha Tremayne Hill, Gabriel H. Gracia-Maldondo, Mary K. Leonard, Amanda R. Harper, Kathleen L. Tober, Tatiana M. Oberyszyn, Madhavi P. Kadakia

Biochemistry and Molecular Biology Faculty Publications

ΔNp63α, a proto-oncogene, is up-regulated in non-melanoma skin cancers and directly regulates the expression of both Vitamin D receptor (VDR) and phosphatase and tensin homologue deleted on chromosome ten (PTEN). Since ΔNp63α has been shown to inhibit cell invasion via regulation of VDR, we wanted to determine whether dietary Vitamin D₃ protected against UVB induced tumor formation in SKH-1 mice, a model for squamous cell carcinoma development. We examined whether there was a correlation between dietary Vitamin D₃ and ΔNp63α, VDR or PTEN expression in vivo in SKH-1 mice chronically exposed to UVB radiation and fed chow containing …

Activation Of Dna Damage Checkpoint Pathways During Skeletal Myoblast Differentiation And Apoptosis, Mofetoluwa Oluwasanmi, Greg Kliment, Crystal M. Weyman

Undergraduate Research Posters 2014

A subset of skeletal myoblasts undergo apoptosis rather than differentiation when cultured in differentiation media (DM: absence of growth factors). While the muscle regulatory transcription factor MyoD is known to control the process of differentiation, our lab has recently discovered that MyoD is also controlling the apoptotic process in response to culture in DM by direct up-regulation of the pro-apoptotic Bcl2 family member PUMA. We similarly discovered that MyoD plays a role in the increased expression of PUMA and apoptosis in response to the DNA damaging agent, etoposide. This led to the hypothesis that culture in DM may lead to …

Nack Is An Integral Component Of The Notch Transcriptional Activation Complex And Is Critical For Development And Tumorigenesis, Kelly L Weaver, Marie-Clotilde Alves-Guerra, Ke Jin, Zhiqiang Wang, Xiaoqing Han, Prathibha Ranganathan, Xiaoxia Zhu, Thiago Dasilva, Wei Liu, Francesca Ratti, Renee M Demarest, Cristos Tzimas, Meghan Rice, Rodrigo Vasquez-Del Carpio, Nadia Dahmane, David J Robbins, Anthony J Capobianco

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The Notch signaling pathway governs many distinct cellular processes by regulating transcriptional programs. The transcriptional response initiated by Notch is highly cell context dependent, indicating that multiple factors influence Notch target gene selection and activity. However, the mechanism by which Notch drives target gene transcription is not well understood. Herein, we identify and characterize a novel Notch-interacting protein, Notch activation complex kinase (NACK), which acts as a Notch transcriptional coactivator. We show that NACK associates with the Notch transcriptional activation complex on DNA, mediates Notch transcriptional activity, and is required for Notch-mediated tumorigenesis. We demonstrate that Notch1 and NACK are …