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Articles 1 - 30 of 483

Full-Text Articles in Molecular Biology

Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer Mar 2020

Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer

Poisonous Plant Research (PPR)

Locoweeds are the most widespread poisonous plant problem in the world and have been reported in the Western United States since the 1800s, causing tremendous losses in livestock. Consumption of locoweeds by grazing animals stimulates the neurological disease, locoism, characterized by weight loss, ataxia, and lack of muscular coordination. The name locoweed is used for Astragalus and Oxytropis species known to contain swainsonine, the toxic principle produced by the plant endophytic fungus Undifilum. Astragalus includes 2,500-3,000 species and many varieties that have almost identical morphological characteristics that overlap among species, leading to improper identification. Therefore, the aim of ...


Screening For Antibiotic-Producers In Soil From A Garden, Long Tran, Dr. Lori Scott Jan 2020

Screening For Antibiotic-Producers In Soil From A Garden, Long Tran, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

Multidrug-resistant pathogens are the leading cause of nosocomial infection, which killed more than 30,000 people in the United States every year. Among these, ESKAPE strains bugs, which comprise six highly drug-resistant bacteria, pose the greatest challenge to the healthcare system. In order to fight the antibiotic-resistant crises, novel antibiotic-producers must be discovered. This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student sourcing antibiotic discovery from the soil. Pseudomonas was revealed to produce a zone of inhibition against Bacillus subtilis on LB media. The next ...


Identification Of Uncommon Antibiotic-Producing Illinois Soil Isolates, Lesly Muniz, Dr. Lori Scott Jan 2020

Identification Of Uncommon Antibiotic-Producing Illinois Soil Isolates, Lesly Muniz, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student sourcing antibiotic discovery from the soil. We researched tester strains B. subtilis and E. coli from the soil isolates obtained. We further verified if the isolates were common antibiotic bacteria. Unfortunately, this project heavily relied on biochemical tests, colony morphology, and Gram stains to reject or fail to reject our hypothesis. Our goal was to discover new antibiotic-producing bacteria that could be beneficial in combating ESKAPE strains. A proper PCR and DNA extraction would be required ...


Pseudomonas And Bacillus Soil Isolates Produce Antibiotics, Chelsea Brandt, Dr. Lori Scott Jan 2020

Pseudomonas And Bacillus Soil Isolates Produce Antibiotics, Chelsea Brandt, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

The recent emergence of antibiotic resistance bacterial strains presents a significant challenge and threat to human healthcare. While new methods of treatment such as bacteriophage therapy and combinations of existing antibiotics are being researched, the human population is in dire need of new antibiotics to replace those that are ineffective. This research addresses this need by identifying antibiotic producing bacteria in a soil sample from Davenport, IA. This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on studentsourcing antibiotic discovery from soil. Microbiology lab techniques and 16S ...


Role Of Microrna-483 In Pancreatic Β-Cells, Jackson Waugh Jan 2020

Role Of Microrna-483 In Pancreatic Β-Cells, Jackson Waugh

Dissertations, Master's Theses and Master's Reports

Insulin is an essential hormone produced by β-cells in the pancreas. The release of insulin is tightly regulated in healthy people in order to control blood sugar level in our body. However, people with Type 2 Diabetes have insufficient insulin secretion from pancreatic β-cells, leaving to high blood sugar (hyperglycemia) and β-cell failure. microRNAs (miRNAs or miR) are newly discovered small regulatory molecules and have emerged as important regulator of cell growth, differentiation, and organ function. Altered miRNA function has been implicated in the pathogenesis of a variety of human disease, including diabetes. In this report, we focus on dissecting ...


The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd Jan 2020

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry ...


Peroxiredoxin 6 And Inflammation In Alzheimer's Disease, Jared Ferrell-Penniman Dec 2019

Peroxiredoxin 6 And Inflammation In Alzheimer's Disease, Jared Ferrell-Penniman

Biological Sciences Theses and Dissertations

Alzheimer’s disease (AD) is known for its debilitating symptoms and poor prognosis. However, despite intense research into neurodegenerative diseases, there are few therapies targeted at the underlying mechanisms of the disease. Oxidative stress (OS) and inflammation are cellular phenomena thought to be key to the progression of the disease. Critically, peroxiredoxin 6 (Prx6), an antioxidant protein with multiple functions, has been identified from mammalian studies as a potential regulator of both OS and inflammation that may have a specific effect on AD. This project seeks to elucidate the role of Prx6 in AD as well as the underlying mechanisms ...


Elucidating Enhancer Function In Epidermal Development And Filaggrin Loss-Of-Function Variants In African American Atopic Dermatitis, Mary Elizabeth Mathyer Dec 2019

Elucidating Enhancer Function In Epidermal Development And Filaggrin Loss-Of-Function Variants In African American Atopic Dermatitis, Mary Elizabeth Mathyer

Arts & Sciences Electronic Theses and Dissertations

The epidermis is the outermost tissue of the skin and provides the body’s first line of defense against external assaults. The epidermis is primarily composed of keratinocytes that terminally differentiate and rise apically toward the surface to form the semipermeable barrier of the skin. A hallmark of keratinocyte terminal differentiation is the expression of genes from the Epidermal Differentiation Complex (EDC) locus. Many of the EDC protein products contribute to the structural integrity of the skin barrier, evidenced by several gene knockouts such as loricrin, and even genetic variation within gene coding sequences, that modulate the integrity of the ...


A Noncanonical Function Of The Telomerase Rna Component In Human Embryonic Stem Cells, Kirsten Ann Brenner Dec 2019

A Noncanonical Function Of The Telomerase Rna Component In Human Embryonic Stem Cells, Kirsten Ann Brenner

Arts & Sciences Electronic Theses and Dissertations

Telomeres are stretches of TTAGGG nucleotide repeats located at the ends of linear chromosomes that shorten with progressive cell division and prevent genomic instability at the cost of limiting a cell’s capacity to proliferate. This limitation can be overcome by telomerase, a ribonucleoprotein complex that elongates telomeres via reverse-transcription of the template telomerase RNA component (TERC). Recent studies have reported potential functions of TERC outside of its role in telomere maintenance. These noncanonical functions of TERC are however poorly defined, and the molecular mechanisms and biological relevance behind such functions remain elusive. Here, we generated conditional TERC knock-out human ...


Investigating Growth Performance And Intestinal Barrier Integrity In Heat-Stressed Modern Broilers And Their Ancestor Jungle Fowl, Travis Tabler Dec 2019

Investigating Growth Performance And Intestinal Barrier Integrity In Heat-Stressed Modern Broilers And Their Ancestor Jungle Fowl, Travis Tabler

Theses and Dissertations

Heat stress (HS) has a negative effect on poultry production sustainability due to its adverse consequence on bird welfare, health, growth, and mortality. Although modern broilers have greater gut mass and higher energy use efficiency than unselected birds, they are more vulnerable to HS that induces “leaky gut syndrome,” or increased intestinal permeability. The aim of the current study was to determine the effect of HS on growth performance and gut barrier integrity in three modern broiler lines and their ancestor the Jungle Fowl. Four chicken populations including Giant Jungle Fowl (JF), Athens Canadian Random Bred (ACRB), 1995 Arkansas Random ...


Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich Dec 2019

Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich

Biomedical Sciences ETDs

Salivary gland adenoid cystic carcinoma (ACC) is an aggressive tumor with a tendency to infiltrate surrounding nerves and metastasize to distant sites. The standard treatment often fails to control local tumor recurrence and distant metastases and no approved targeted therapeutic options exist for these tumors. The goal of our studies was to reveal the molecular mechanisms driving ACC tumor development and novel drug targets to improve patient morbidity and mortality.

We first analyzed clinical and RNA-sequencing (RNA-seq) data for 68 formalin-fixed paraffin-embedded (FFPE) ACC tumor samples and described previously unappreciated molecular heterogeneity that predicts patient outcome. The poor outcome subgroup ...


Systems Analyses Of Key Metabolic Modules Of Floral And Extrafloral Nectaries Of Cotton, Elizabeth C. Chatt, Siti-Nabilla Mahalim, Nur-Aziatull Mohd-Fadzil, Rahul Roy, Peter M. Klinkenberg, Harry T. Horner, Marshall Hampton, Clay J. Carter, Basil J. Nikolau Nov 2019

Systems Analyses Of Key Metabolic Modules Of Floral And Extrafloral Nectaries Of Cotton, Elizabeth C. Chatt, Siti-Nabilla Mahalim, Nur-Aziatull Mohd-Fadzil, Rahul Roy, Peter M. Klinkenberg, Harry T. Horner, Marshall Hampton, Clay J. Carter, Basil J. Nikolau

Genetics, Development and Cell Biology Publications

Nectar is a primary reward mediating plant-animal mutualisms to improve plant fitness and reproductive success. In Gossypium hirsutum (cotton), four distinct trichomatic nectaries develop, one floral and three extrafloral. The secreted floral and extrafloral nectars serve different purposes, with the floral nectar attracting bees to promote pollination and the extrafloral nectar attracting predatory insects as a means of indirect resistance from herbivores. Cotton therefore provides an ideal system to contrast mechanisms of nectar production and nectar composition between floral and extrafloral nectaries. Here, we report the transcriptome, ultrastructure, and metabolite spatial distribution using mass spectrometric imaging of the four cotton ...


#3 - Generation Of Sult4a1 Gene Mutations In Sh-Sy5y Cells, Elisabeth Bradberry, Frank Crittenden Nov 2019

#3 - Generation Of Sult4a1 Gene Mutations In Sh-Sy5y Cells, Elisabeth Bradberry, Frank Crittenden

Georgia Undergraduate Research Conference (GURC)

The cytosolic sulfotransferases (SULT) are a superfamily of enzymes that catalyze the metabolism of various substrates throughout the body. One member, SULT4A1, has no known substrates and is highly conserved among all vertebrates which is not a shared characteristic among the SULT family. Also unique among the SULTs, SULT4A1 localizes with mitochondria of neurons. Recent reports have suggested that this protein is believed play a protective role against oxidative stress. The goal of this project was to generate a SH-SY5Y cell line with a SULT4A1 gene deletion using CRISPR gene-editing technology. These neuroblastoma cells were used because of their ease ...


Cyp72a Enzymes Catalyse 13-Hydrolyzation Of Gibberellins, Juan He, Qingwen Chen, Peiyong Xin, Jia Yuan, Yihua Ma, Xuemei Wang, Meimei Xu, Jinfang Chu, Reuben J. Peters, Guodong Wang Sep 2019

Cyp72a Enzymes Catalyse 13-Hydrolyzation Of Gibberellins, Juan He, Qingwen Chen, Peiyong Xin, Jia Yuan, Yihua Ma, Xuemei Wang, Meimei Xu, Jinfang Chu, Reuben J. Peters, Guodong Wang

Biochemistry, Biophysics and Molecular Biology Publications

Bioactive gibberellins (GAs, diterpenes) are essential hormones in land plants, controlling many aspects of plant growth and developments. In flowering plants, 13-OH (low bioactivity; such as GA1) and 13-H GAs (high bioactivity; such as GA4) frequently coexist. However, the bona fide GA 13-hydroxylase and its physiological functions in Arabidopsis remain unknown. Here, we report that novel cytochrome P450 genes (CYP72A9 and its homologs) encode active GA 13- hydroxylases in Brassicaceae plants. CYP72A9-overexpressing plants exhibited semi-dwarfism, which was caused by significant reduction in GA4 levels. Biochemical assays revealed that recombinant CYP72A9 protein catalyzed the conversion from 13-H GAs to the corresponding ...


Gene Pyramids And The Balancing Act Of Keeping Pests At Bay, Gustavo C. Macintosh Sep 2019

Gene Pyramids And The Balancing Act Of Keeping Pests At Bay, Gustavo C. Macintosh

Biochemistry, Biophysics and Molecular Biology Publications

Pyramiding R genes is a common strategy used by breeders to enhance resistance and increase durability of resistance in crops. However, the molecular mechanisms that mediate R gene interactions are not known. Kamphuis et al. (2019) analyzed Medicago truncatula plants carrying two genes that confer resistance to bluegreen aphids. They identified a potential phytohormone crosstalk triggered by the combined R gene action in response to aphid feeding that enhances resistance and minimizes R gene-associated fitness costs to the plant.


Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating Jul 2019

Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating

Aileen Keating

Insulin, elevated during obesity, regulates xenobiotic biotransformation enzymes, potentially through phosphatidylinositol 3-kinase (PI3K) signaling, in extraovarian tissues. PI3K regulates oocyte viability, follicular activation, and ovarian chemical biotransformation. 7,12-Dimethylbenz[a]anthracene (DMBA), a carcinogen and ovotoxicant, destroys all stages of follicles, leading to premature ovarian failure. Obesity has been reported to promote DMBA-induced tumors, but it remains unknown whether obesity affects ovarian xenobiotic metabolism. Therefore, we investigated ovarian expression of xenobiotic metabolism genes—microsomal epoxide hydrolase (Ephx1), glutathione S-transferase (GST) class Pi (Gstp1) and class mu 1 (Gstm1), and PI3K-signaling members (protein kinase B [AKT] alpha [Akt1], beta [Akt2], and ...


The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy May 2019

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

All Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims ...


Pesticides And Parkinson's: An Investigation Of The Effect Of Roundup Exposure On Drosophila Melanogaster, Siobhan O'Neill Apr 2019

Pesticides And Parkinson's: An Investigation Of The Effect Of Roundup Exposure On Drosophila Melanogaster, Siobhan O'Neill

Carroll College Student Undergraduate Research Festival

From commercial farms to private households, Roundup is the most commonly used herbicide in the United States. In recent years, exposure to Roundup has been correlated with a variety of health problems including Celiac Disease, birth defects, kidney and liver diseases, Alzheimer's Disease, and Parkinson's Disease. To date, the use of Roundup has been banned or restricted in several foreign countries, including the Netherlands, Portugal, Germany and Italy, because it has been classified as a possible carcinogen by the World Health Organization. The goal of this research was to determine the effects of Roundup exposure on dopaminergic neurons ...


Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton Apr 2019

Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton

Biochemistry, Biophysics and Molecular Biology Publications

Aptamers are in vitro selected oligonucleotides (DNA, RNA, oligos with modified nucleotides) that can have high affinity and specificity for a broad range of potential targets with high affinity and specificity. Here we focus on their applications as biosensors in the diagnostic field, although they can also be used as therapeutic agents. A small number of peptide aptamers have also been identified. In analytical settings, aptamers have the potential to extend the limit of current techniques as they offer many advantages over antibodies and can be used for real-time biomarker detection, cancer clinical testing, and detection of infectious microorganisms and ...


How A Cell Knows Where To Divide: Oscillation Of Mind In Vivo, Colby Ferreira Apr 2019

How A Cell Knows Where To Divide: Oscillation Of Mind In Vivo, Colby Ferreira

Senior Honors Projects

Over two-million people in the United States are infected by antibiotic resistant bacteria each year. Of this number 23,000 die from these infections and other complications. Due to this, novel antibiotic targets are constantly being investigated. One process in prokaryotes that holds promise is cellular division. Bacterial cells grow and reproduce using a series of proteins known as the cell division machinery. This machinery enables the division of the parental cell into two identical daughter cells. The cell division machinery is similar between bacterial taxa, making it an ideal target for new classes of antibiotics. Therefore, understanding the molecular ...


Promoter Library Designed For Fine-Tuned Gene Expression In Pichia Pastoris, Franz S. Hartner, Claudia Ruth, David Langenegger, Sabrina N. Johnson, Petr Hyka, Geoff P. Lin-Cereghino, Joan Lin-Cereghino, Karin Kovar, James Cregg, Anton Glieder Mar 2019

Promoter Library Designed For Fine-Tuned Gene Expression In Pichia Pastoris, Franz S. Hartner, Claudia Ruth, David Langenegger, Sabrina N. Johnson, Petr Hyka, Geoff P. Lin-Cereghino, Joan Lin-Cereghino, Karin Kovar, James Cregg, Anton Glieder

Joan Lin-Cereghino

Although frequently used as protein production host, there is only a limited set of promoters available to drive the expression of recombinant proteins in Pichia pastoris. Fine-tuning of gene expression is often needed to maximize product yield and quality. However, for efficient knowledge-based engineering, a better understanding of promoter function is indispensable. Consequently, we created a promoter library by deletion and duplication of putative transcription factor-binding sites within the AOX1 promoter (PAOX1) sequence. This first library initially spanned an activity range between ∼6% and >160% of the wild-type promoter activity. After characterization of the promoter library employing a green ...


Protein Degradation Regulates Phospholipid Biosynthetic Gene Expression In Saccharomyces Cerevisiae, Bryan Salas-Santiago Mar 2019

Protein Degradation Regulates Phospholipid Biosynthetic Gene Expression In Saccharomyces Cerevisiae, Bryan Salas-Santiago

Doctoral Dissertations

Transcriptional regulation of most phospholipid biosynthetic genes in Saccharomyces cerevisiae is coordinated by inositol and choline. Inositol affects phosphatidic acid (PA) intracellular levels. Opi1p interacts physically with PA and is the main repressor of the phospholipid biosynthetic genes. It is localized in the endoplasmic reticulum (ER) bound to the ER membrane protein Scs2p. When PA levels drop, Opi1p is translocated into the nucleus repressing most phospholipid biosynthetic genes. The OPI1 locus was identified in a screen looking for overproduction and excretion of inositol (Opi-). Opi- mutants are generally associated with a defect in repression of the ...


The Role Of H3k4 Methyltransferases In Drosophila Memory, Nicholas Raun Jan 2019

The Role Of H3k4 Methyltransferases In Drosophila Memory, Nicholas Raun

Electronic Thesis and Dissertation Repository

Gene transcription required for long-term memory requires the modification of histones. However, there are still many uncertainties about the identity and spatial expression of genes regulated by histone modifications during memory related processes. In this project I examined the role of Drosophila melanogaster methyltransferases Set1 and trx in courtship memory. Genetic knockdown of Set1 and trx in the mushroom body (MB) revealed that Set1 was necessary for short- and long-term memory, while trx was only required for long-term memory. Transcriptional profiling of MBs following trx-knockdown revealed expression changes in MB-enriched genes and genes involved in RNA processing. Among the ...


Unraveling The Beta Cell Translatome: Elucidation Of An Erk/Hnrnpk/Jund Axis, Austin Lewis Good Jan 2019

Unraveling The Beta Cell Translatome: Elucidation Of An Erk/Hnrnpk/Jund Axis, Austin Lewis Good

Publicly Accessible Penn Dissertations

In type 2 diabetes, oxidative stress contributes to the dysfunction and loss of pancreatic β cells. A highly conserved feature of the cellular response to stress is the regulation of mRNA translation, however, the mechanisms underlying this process in β cells are not fully understood. Here we use TRAP-seq to examine changes in the ribosome occupancy of mRNAs during conditions associated with β cell dysfunction, leading us to identify a cohort of translationally regulated genes with 3’UTR enrichment of a cytosine-rich motif. Of particular interest was the gene encoding JUND, a transcription factor with anti-oxidant functions in other cell ...


Nuclear Pore Proteins In Regulation Of Chromatin State And Gene Expression, Terra Kuhn Jan 2019

Nuclear Pore Proteins In Regulation Of Chromatin State And Gene Expression, Terra Kuhn

Publicly Accessible Penn Dissertations

Nuclear pore complexes are best known for their regulation of nucleocytoplasmic transport as integral components of the eukaryotic nuclear envelope. Over the years, their importance in regulation of genome function has become apparent. Many of the 30 individual nuclear pore proteins, Nups, have been found to play distinct roles interacting with and regulating various genomic targets, especially in a cell-type specific manner. The mechanism behind this regulation is often unknown. We have developed a method by which to study the roles of Nups on chromatin using an ectopic-tethering system. Drosophila melanogaster provide a powerful tool with which to combine many ...


Systems Biology Of Gene Regulation Across Scales: From Single Molecules To Cellular Identities, Ian Alexander Mellis Jan 2019

Systems Biology Of Gene Regulation Across Scales: From Single Molecules To Cellular Identities, Ian Alexander Mellis

Publicly Accessible Penn Dissertations

Gene regulation takes many forms and is responsible for phenotypes at the scale of individual molecules up through the scale of complex tissue functions. At the smallest level, single-base modifications of individual mRNA molecules transcribed from the same gene can lead to functionally different protein products. In the first chapter of this thesis, I develop a new method, inoFISH, and associated analytical tools to visualize and quantify RNA editing with single molecule resolution in single mammalian cells. Using this new method in conjunction with mathematical modeling I show that the heterogeneity of single-cell mRNA editing rates across a population depends ...


Epigenetic Variation In A Reptile With Temperature-Dependent Sex Determination And Inspiring A Diverse Future For Stem, Daniela Victoria Flores Jan 2019

Epigenetic Variation In A Reptile With Temperature-Dependent Sex Determination And Inspiring A Diverse Future For Stem, Daniela Victoria Flores

Graduate Theses and Dissertations

Vertebrates with temperature-dependent sex determination (TSD), a mechanism that relies on incubation temperature to irreversibly determine the sex of developing embryos, are threatened by ongoing changes in climate and local environmental conditions. Previous studies have suggested that behavioral and molecular plasticity in this system may provide opportunities for these species to adapt to these changes. Although decades of research have uncovered key aspects, a complete molecular mechanism of TSD remains elusive. Epigenetic studies have the potential to unlock crucial information previously cryptic in traditional genetic studies. Recent studies have shown that environmental factors and maternal effects can greatly influence an ...


Analysis And Characterization Of The Choline-Utilizing Microcompartment In Uropathogenic E. Coli 536, Taylor Irene Herring Jan 2019

Analysis And Characterization Of The Choline-Utilizing Microcompartment In Uropathogenic E. Coli 536, Taylor Irene Herring

Graduate Theses and Dissertations

Bacterial microcompartments (MCPs) are subcellular organelles that are widespread among bacteria. MCPs consist of metabolic enzymes encapsulated within a protein shell and their function is to increase the efficiency of metabolic processes in part by sequestering toxic and volatile intermediates. MCPs are found in about 20% of bacteria. In several cases, MCP production is correlated to bacterial pathogenesis. In addition, because of their metabolic role in the human gut microbiome, MCPs are linked to cancer and heart disease. Only three of ten MCP types have been well-studied. Recently, a new type of MCP that is used to metabolize choline under ...


The Ins And Outs Of Autophagic Ribosome Turnover, Zakayo Kazibwe, Ang-Yu Liu, Gustavo C. Macintosh, Diane C. Bassham Jan 2019

The Ins And Outs Of Autophagic Ribosome Turnover, Zakayo Kazibwe, Ang-Yu Liu, Gustavo C. Macintosh, Diane C. Bassham

Biochemistry, Biophysics and Molecular Biology Publications

Ribosomes are essential for protein synthesis in all organisms and their biogenesis and number are tightly controlled to maintain homeostasis in changing environmental conditions. While ribosome assembly and quality control mechanisms have been extensively studied, our understanding of ribosome degradation is limited. In yeast or animal cells, ribosomes are degraded after transfer into the vacuole or lysosome by ribophagy or nonselective autophagy, and ribosomal RNA can also be transferred directly across the lysosomal membrane by RNautophagy. In plants, ribosomal RNA is degraded by the vacuolar T2 ribonuclease RNS2 after transport by autophagy-related mechanisms, although it is unknown if a selective ...


Genetic And Epigenetic Modifiers Of C9orf72 Expression In Neurodegenerative Disease, Christopher Cali Jan 2019

Genetic And Epigenetic Modifiers Of C9orf72 Expression In Neurodegenerative Disease, Christopher Cali

Publicly Accessible Penn Dissertations

Repeat expansion mutations in the gene C9orf72 are the most common cause of the fatal neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal degeneration (FTD). The molecular mechanisms that contribute to these diseases are still not fully understood. In this dissertation, we explore mechanisms associated with repeat expansions in C9orf72 that alter gene expression and contribute to disease. In chapter 2, we develop a novel method of targeted DNA methylation in order to study how epigenetic changes in C9orf72 expansion carriers contribute to disease pathways. We find that C9orf72 promoter hypermethylation is sufficient to reduce gene expression and induce heterochromatin ...