Life Sciences Commons^™

The Role Of The Cdk8 Kinase Module In Maintaining Proteostasis, Stephen Willis

Theses and Dissertations

The underlying etiology of numerous disease states results from perturbations in the maintenance of cellular proteostasis. Carcinogenesis relies on these perturbations to foster uncontrolled cell growth and eventual metastases, while neurodegenerative diseases are a consequence of such perturbations. Control of these processes occurs at numerous molecular levels, commonly starting with transcription. A key transcriptional complex that is involved is the CDK8 Kinase Module (CKM). The CKM is conserved from yeast to man, forming a tetrameric complex consisting of MED12, MED13, CDK8, and CCNC. The CKM has not only been implicated in a variety of cancers but also in a spectrum …

Investigating The Impact Of Transcription On Mutation Rates, Sarah Patterson

Theses and Dissertations

tRNA genes are highly transcribed and perform one of the most fundamental cellular functions. Although a universal pattern observed across all three domains of life is that highly transcribed genes tend to evolve slowly, tRNA genes have been shown previously to evolve rapidly. This rapid sequence evolution could result from relaxed selection, increased mutation rate, or a combination of both. Here, we use mutation-accumulation line sequencing data to show that tRNA genes accumulate more mutations than other gene types. Our results indicate that this elevated mutation rate is a consequence of both elevated transcription-associated mutagenesis and a lack of transcription-coupled …

Modeling Nonsegmented Negative-Strand Rna Virus (Nnsv) Transcription With Ejective Polymerase Collisions And Biased Diffusion, Felipe-Andres Piedra

Research Symposium

Background: The textbook model of NNSV transcription predicts a gene expression gradient. However, multiple studies show non-gradient gene expression patterns or data inconsistent with a simple gradient. Regarding the latter, several studies show a dramatic decrease in gene expression over the last two genes of the respiratory syncytial virus (RSV) genome (a highly studied NNSV). The textbook model cannot explain these phenomena.

Methods: Computational models of RSV and vesicular stomatitis virus (VSV – another highly studied NNSV) transcription were written in the Python programming language using the Scientific Python Development Environment. The model code is freely available on GitHub: …

Early Chromosome Condensation By Xist Builds A-Repeat Rna Density That Facilitates Gene Silencing, M. Valledor, M. Byron, B. Dumas, Dawn M. Carone, L. L. Hall, J. B. Lawrence

Biology Faculty Works

XIST RNA triggers chromosome-wide gene silencing and condenses an active chromosome into a Barr body. Here, we use inducible human XIST to examine early steps in the process, showing that XIST modifies cytoarchitecture before widespread gene silencing. In just 2–4 h, barely visible transcripts populate the large “sparse zone” surrounding the smaller “dense zone”; importantly, density zones exhibit different chromatin impacts. Sparse transcripts immediately trigger immunofluorescence for H2AK119ub and CIZ1, a matrix protein. H3K27me3 appears hours later in the dense zone, which enlarges with chromosome condensation. Genes examined are silenced after compaction of the RNA/DNA territory. Insights into this come …

Investigating The Sequence Landscape In The Drosophila Initiator Core Promoter Element Using An Enhanced Marz Algorithm, Jacqueline Dresch, Regan D. Conrad, Daniel Klonaros, Robert Drewell

Biology

The core promoter elements are important DNA sequences for the regulation of RNA polymerase II transcription in eukaryotic cells. Despite the broad evolutionary conservation of these elements, there is extensive variation in the nucleotide composition of the actual sequences. In this study, we aim to improve our understanding of the complexity of this sequence variation in the TATA box and initiator core promoter elements in Drosophila melanogaster. Using computational approaches, including an enhanced version of our previously developed MARZ algorithm that utilizes gapped nucleotide matrices, several sequence landscape features are uncovered, including an interdependency between the nucleotides in position 2 …

Characterization Of Protein-Protein Interactions In Quorum-Sensing Receptors From Gram Negative Bacteria, Jessica Schuh

Biological Sciences

Pseudomonas aeruginosa is a bacterium capable of causing disease in immunocompromised individuals and individuals with underlying lung disorders. It controls the expression of a subset of its genes through quorum sensing, which is a cell-cell communication system involved in mediating the transition from individual to group behaviors. Group behaviors are cellular processes undertaken by the cell that are beneficial to the collective, such as biofilm formation – a key component of pathogenesis in the human lung. They rely on the production, accumulation, detection, and response to signal molecules called autoinducers. There are two acyl-homoserine lactone autoinducer quorum sensing systems in …

Transcriptional Silencing Of Cdk18 And Its Role In Lung Carcinogenesis Of Brg1-Mutant Lung Cancers, Loryn M. Phillips

Biology ETDs

BRG1 is mutated in 10% of lung cancers, making this mutation clinically relevant. The downstream effects of BRG1 included significantly affecting the cell cycle control and chromosomal replication pathway. CDK18, a cyclin-dependent kinase, was determined to be the gene with significantly decreased expression (p

Genetic Stop Signs: Nontraditional Sequences That Terminate Rna Production, Christina Iverson, Samuel Scott

Library/Life Sciences Undergraduate Poster Competition 2023

3rd place open house

Gene expression can change everything about the identity of a bacterial cell. This process begins when the protein RNA polymerase reads a DNA strand and produces, or transcribes, a matching messenger RNA sequence. This RNA sequence will then be read by a protein-building complex which builds a protein encoded by the RNA. When RNA polymerase finishes producing the RNA sequence, the RNA polymerase will fall off the DNA strand, known as transcription termination. Currently, there are two known mechanisms for transcription termination. We believe that there may be more unknown mechanisms for termination.

Characterizing The Dynamic Localization Of Cmi In Early Drosophila Development, Asra Habibullah

Master's Theses

The COMPASS-like family of lysine methyltransferases, MLR/MLX complexes, are epigenetic regulators that are essential for normal development through the methylation of the fourth lysine residue on histone 3 (H3K4), a universal epigenetic mark associated with active transcription. This family of complexes is highly conserved from yeast to mammals and the genes encoding the human MLR complexes have been associated with various developmental diseases and cancers (Dingwall and Fagan, 2019). In D. melanogaster, the enzymatic methyltransferase core of this complex is composed of two proteins: Cara Mitad (Cmi, also known as Lpt) and Trithorax-related (Trr). Although these proteins have been shown …

Molecular Mechanisms Of Diverse Auxin Responses During Plant Growth And Development, Yang Zhang, Jiajie Yu, Xiuyue Xu, Ruiqi Wang, Yingying Liu, Shan Huang, Hairong Wei, Zhigang Wei

Michigan Tech Publications

The plant hormone auxin acts as a signaling molecule to regulate numerous developmental processes throughout all stages of plant growth. Understanding how auxin regulates various physiological and developmental processes has been a hot topic and an intriguing field. Recent studies have unveiled more molecular details into how diverse auxin responses function in every aspect of plant growth and development. In this review, we systematically summarized and classified the molecular mechanisms of diverse auxin responses, and comprehensively elaborated the characteristics and multilevel regulation mechanisms of the canonical transcriptional auxin response. On this basis, we described the characteristics and differences between different …

Determining The Roles Of The Oligomerization And C-Terminal Domains In Mutant P53 Gain-Of-Function Activities, George K. Annor

Dissertations, Theses, and Capstone Projects

The tumor suppressor p53 (TP53) gene is often mutated in cancer, with missense mutations found in the central DNA binding domain, and less often in the oligomerization domain (OD) and C-terminal domain (CTD). The OD and CTD have been found to be critical for the tumor suppressor functionality of wild-type p53 (wtp53). Specific missense mutations in the DNA binding domain have been found to confer new gain-of-function (GOF) activities. Mutations that destabilize tetramer formation, or deletion of key lysine residues within the CTD, downregulate the ability of wtp53 to transactivate (increase the rate of transcription of) its target …

The Transcriptional Regulator Ctra Controls Gene Expression In Alphaproteobacteria Phages: Evidence For A Lytic Deferment Pathway, Elia Mascolo, Satish Adhikari, Steven M. Caruso, Tagide Decarvalho, Anna Folch Salvador, Joan Serra-Sagristà, Ry Young, Ivan Erill, Patrick D. Curtis

Faculty and Student Publications

Pilitropic and flagellotropic phages adsorb to bacterial pili and flagella. These phages have long been used to investigate multiple aspects of bacterial physiology, such as the cell cycle control in the Caulobacterales. Targeting cellular appendages for adsorption effectively constrains the population of infectable hosts, suggesting that phages may have developed strategies to maximize their infective yield. Brevundimonas phage vB_BsubS-Delta is a recently characterized pilitropic phage infecting the Alphaproteobacterium Brevundimonas subvibrioides. Like other Caulobacterales, B. subvibrioides divides asymmetrically and its cell cycle is governed by multiple transcriptional regulators, including the master regulator CtrA. Genomic characterization of phage vB_BsubS-Delta identified the presence …

Characterizing The Functional Role Of Transcription Factor E In Archaeal Transcription, Madolyn Hofstetter, Michael Bartlett

Student Research Symposium

Archaea and eukaryotes share many homologous proteins and essential mechanisms for survival and DNA replication. It is proposed that Archaea are the ancestors of eukaryotes, suggesting that eukaryotic transcription evolved from the basic archaeal mechanisms. By studying the fundamentals of archaeal transcription, we are in turn understanding more about how eukaryotic transcription functions. Many human diseases are linked to mishaps and mutations in the process of transcribing DNA to mRNA, so it is essential to explore structures and how mutations in these structures affect the essential function of transcription, and if these mutations also play a role in human disease.

Roles Of Small Rnas And Paralogous Proteins In Bacillus Anthracis Virulence Gene Regulation, Ileana Corsi

Dissertations & Theses (Open Access)

Bacteria have evolved a myriad of regulatory mechanisms to control gene expression. One of the most common mechanisms is post-transcriptional control through the function of small regulatory RNAs (sRNAs). Small regulatory RNAs (sRNAs) are short transcripts that base-pair to mRNA targets or interact with regulatory proteins. sRNA function has been studied extensively in Gram-negative bacteria; comparatively less is known about sRNAs in Firmicutes. In this dissertation, I investigated two sRNAs encoded within the virulence plasmid pXO1 of Bacillus anthracis, the causative agent of anthrax. The sRNAs, named “XrrA and XrrB” (for p­XO1-encoded regulatory RNA) are abundant and highly stable …

The Central Dogma: Gene Expression, Ayisha Sookdeo

Open Educational Resources

In this lesson plan, students will learn the basic structure and function of DNA and RNA. They will also learn the process of gene expression. Finally, students will learn about the scientific contributor, Ernest Everest Just, and his contributions to the field of Biology.

Generating A Colorimetric Ssa4 Transcript Export Reporter For Multicopy Suppression Screen In S. Cerevisiae, Zaid Hatem

Belmont University Research Symposium (BURS)

The export of mRNA from the nucleus to the cytoplasm is a regulatory point that is essential to the pathway of gene expression in eukaryotic cells. The export of mRNA transcripts is mediated through selective doorways called the nuclear pore complexes (NPC). Additionally, there are proteins associated with the nuclear pore complex that assist in facilitating the export. This includes association with the export receptor, Mex67, which binds to the transcript and ferries it through NPCs. During cellular stress, such as heat shock, the export of housekeeping mRNA transcripts is halted, forcing these transcripts to remain inside the nucleus and …

The Effect Of Anti-Aging Treatment On Expression Of Aging Markers In A Mouse Model Of Huntington Disease, Mary Isabelle E. Guerra

Honors Undergraduate Theses

Huntington disease (HD) is a fatal neurodegenerative disease caused by CAG tract expansion in the huntingtin (HTT) gene, which results in production of mutant huntingtin (mtHTT) protein. Although mtHTT is expressed throughout life, onset of HD symptoms typically begins in mid-life, around 35 to 50 years of age. Characteristic HD symptoms include motor, cognitive, and psychiatric abnormalities. The emergence of symptoms in adulthood suggests that aging may play a role in HD pathogenesis. Furthermore, markers of accelerated aging can be observed in HD patients, including telomere attrition, epigenetic alterations, and mitochondrial dysfunction. Our lab has previously observed that …

Establishing A Biochemical System For The Purification And Atpase Activity Of Gst-Dbp5, Sarah R. Utley, Rachel E. Rigsby Phd, Rebecca L. Adams Phd

Science University Research Symposium (SURS)

The export of mRNA out of the nucleus is a crucial step for eukaryotic gene expression. The export of mRNA transcripts is aided by Mex67, which allows export through the nuclear pore complex doorways in the nuclear envelope. Once out of the nucleus, a protein known as Dbp5, bound to ATP, Gle1, and Nup42 aids in the directionality of mRNA export by helping remove Mex67 from the mRNA strand. Following interaction with RNA, Dbp5 then hydrolyzes ATP so that it unbinds the mRNA, allowing for enzyme recycling. Previous efforts worked towards the purification of Dbp5, but the attempts were unsuccessful …

Low Light Intensity Delays Vegetative Phase Change, Mingli Xu, Tieqiang Hu, R Scott Poethig

Faculty Publications

Plants that develop under low light (LL) intensity often display a phenotype known as the “shade tolerance syndrome (STS)”. This syndrome is similar to the phenotype of plants in the juvenile phase of shoot development, but the basis for this similarity is unknown. We tested the hypothesis that the STS is regulated by the same mechanism that regulates the juvenile vegetative phase by examining the effect of LL on rosette development in Arabidopsis (Arabidopsis thaliana). We found that LL prolonged the juvenile vegetative phase and that this was associated with an increase in the expression of the master …

A Functional Characterization Of The Omega (Ω) Subunit Of Rna Polymerase In Staphylococcus Aureus, Shrushti B. Patil

USF Tampa Graduate Theses and Dissertations

In bacteria, RNA polymerase (RNAP) is a well-characterized and highly conserved multi-subunit enzyme complex responsible for transcription of DNA into RNA. The ω subunit (rpoZ/RpoZ), one of the smaller accessory subunits of RNAP, is often overlooked and under-studied, however, particularly in Gram-positive species. We have previously shown that deleting ω impacts the integrity of RNA polymerase in S. aureus, especially the β' subunit, and alters preference of the core enzyme for sigma factors, skewing heavily towards σB instead of the housekeeping σ factor. Consequently, this causes deregulation of myriad transcriptional processes, strongly rewiring gene expression circuits, and ultimately impairing the …

Regulatory Non-Coding Rnas Modulate Transcriptional Activation During B Cell Development, Mary Attaway, Tzippora Chwat-Edelstein, Bao Q. Vuong

Publications and Research

B cells play a significant role in the adaptive immune response by secreting immunoglobulins that can recognize and neutralize foreign antigens. They develop from hematopoietic stem cells, which also give rise to other types of blood cells, such as monocytes, neutrophils, and T cells, wherein specific transcriptional programs define the commitment and subsequent development of these different cell lineages. A number of transcription factors, such as PU.1, E2A, Pax5, and FOXO1, drive B cell development. Mounting evidence demonstrates that non-coding RNAs, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), modulate the expression of these transcription factors directly by binding …

Tet2 Controls The Responses Of Β Cells To Inflammation In Autoimmune Diabetes., Jinxiu Rui, Songyan Deng, Ana Luisa Perdigoto, Gerald Ponath, Romy Kursawe, Nathan Lawlor, Tomokazu Sumida, Maya Levine-Ritterman, Michael L. Stitzel, David Pitt, Jun Lu, Kevan C Herold

Faculty Research 2021

β cells may participate and contribute to their own demise during Type 1 diabetes (T1D). Here we report a role of their expression of Tet2 in regulating immune killing. Tet2 is induced in murine and human β cells with inflammation but its expression is reduced in surviving β cells. Tet2-KO mice that receive WT bone marrow transplants develop insulitis but not diabetes and islet infiltrates do not eliminate β cells even though immune cells from the mice can transfer diabetes to NOD/scid recipients. Tet2-KO recipients are protected from transfer of disease by diabetogenic immune cells.Tet2-KO β cells show reduced expression …

Rna Polymerase Binding Protein A (Rbpa) Regulation Of Mycobacteria Transcription And Sensitivity To Fidaxomicin, Jerome Prusa

Arts & Sciences Electronic Theses and Dissertations

Mycobacterium tuberculosis is the causative agent of the disease tuberculosis (TB) and remains one of the deadliest microorganisms on the planet. The effort to eradicate M. tuberculosis would benefit from the development of novel therapeutics, which requires a detailed understanding of M. tuberculosis physiology. Like all living organisms, M. tuberculosis gene expression requires transcription. Transcription in the phylum Actinobacteria, which includes mycobacteria, is unique because it includes RNA Polymerase Binding Protein A (RbpA) that is essential in both M. tuberculosis and the nonpathogenic model organism Mycobacterium smegmatis. RbpA increases the housekeeping A and housekeeping like B interactions with the RNA …

The 4d Living Genome, Julianna Arlene Sherman Goelzer

Boise State University Theses and Dissertations

Over the last few decades great advances have been made in our understanding of gene expression and the human genome. In 2003 the human genome was sequenced for the first time, allowing us to discover its true importance in human health. While sequencing the human genome was a great advance, it ultimately created more questions than it answered. It is known that the genomic sequence is extremely important in genome regulation, however recent studies have shown that the 4D (spatiotemporal) organization and dynamics of the living genome plays an equally critical role in regulation of gene expression. A key factor …

Transcriptional And Epigenetic Regulation Of Cerebellar Development And Function, Shahriyar Majidi

Arts & Sciences Electronic Theses and Dissertations

Compensation among paralogous transcription factors (TFs) confers genetic robustness of cellular processes. Despite the prevalence of this phenotypic phenomenon, an in vivo genome-scale understanding of how TFs dynamically respond within the chromatin context to paralog depletion is still lacking. We explore this question in the mammalian brain by studying the highly conserved MEF2 family of TFs, which confer phenotypic robustness for neuronal processes across multiple brain regions. The paralogous TFs MEF2A and MEF2D are strongly co-expressed in granule neurons of the cerebellum, the most abundant neurons in the brain. Employing single and double conditional knockout of MEF2A and MEF2D in …

Cyclin C Determines Cell Fate In Response To Oxidative Stress And Proteasome Inhibition, David C. Stieg

Graduate School of Biomedical Sciences Theses and Dissertations

In response to various sources of cellular stress, the coordination of intracellular events is necessary to elicit the appropriate molecular response. In particular, the reprogramming of gene expression by stress-specific transcription factors drives the activation of signaling pathways, triggering either cell survival or regulated cell death pathways. The Cdk8 kinase module (CKM) is a highly conserved transcriptional regulatory complex with a role in this decision. The CKM is composed of Cdk8, its activating partner cyclin C, and two scaffold proteins, Med12 and Med13. The CKM is a detachable subunit of the Mediator complex, which interacts with RNA polymerase II to …

An Evaluation Of Expedited Transcription Methods For School-Age Children’S Narrative Language: Automated Speech Recognition & Real-Time Transcription, Carly Fox

Student Research Symposium

In this study the clinical utility of several expedited transcription methods were evaluated for narrative language samples elicited from school-age children (7;5-11;10) with developmental language disorder (DLD). Transcription methods included real-time transcription (RTT) from both school-based speech language pathologists (SLPs) and trained transcribers (TTs), and automatic speech recognition (ASR). Each method transcribed the same 42 language samples, which were compared to a reference corpus produced using traditional transcription. The accuracy of each method was evaluated using a cross-sectional multilevel model. Results indicated that ASR was significantly more accurate than RTT from both SLPs and TTs. The reliability of scores produced …

Determining Master Regulatory Genes Of Muscle Senescence In The Hawk Moth, Manduca Sexta, Leah J. Naasz

Honors Thesis

ABSTRACT DETERMINING MASTER REGULATORY GENES OF MUSCLE SENESCENCE IN THE HAWK MOTH, MANDUCA SEXTA Leah Naasz Director: Bernie Wone, Ph.D. Skeletal muscle exhibits a gradual deterioration of its functional capabilities as it senesces. While the adverse effects of muscle aging are well-known, the molecular trigger of this degenerative process is unknown. Here, I aim to identify master regulatory genes (i.e., transcription factors) that might be involved in the initiation of the muscle senescence process in our muscle aging model Manduca sexta. This invertebrate adult moth was chosen as the model organism due to its relatively short lifespan, similarity to the …

Mechanism Of Dna Damage Checkpoint (Ddc)- Mediated Repression Of Histone Mrnas And Role Of Acetyl-Coa In Histone Transcription, Madhura Bhagwat

Theses and Dissertations

My dissertation contains two projects. The first project is focused on the mechanism of DNA damage checkpoint (DDC)- mediated repression of histone mRNAs. The second project deals with the role of acetyl-CoA in histone transcription. Proliferating cells coordinate histone and DNA synthesis to maintain correct stoichiometric amounts for chromatin assembly. Histone mRNA levels must be repressed when DNA replication is inhibited to prevent toxicity and genome instability due to free non-chromatinized histone proteins. In the first project we show that, unlike in mammalian cells, DNA replication stress does not trigger decay of histone mRNAs in the yeast Saccharomyces cerevisiae. However, …

Reconstitution Of Pol Ii (G) Responsive Form Of The Human Mediator Complex, Murat Alper Cevher

Turkish Journal of Biology

RNA polymerase II (Pol II) is a 12 subunit protein complex from yeast to human that is required for gene expression. Gdown1 containing Pol II [Pol II (G)] is a special form of Pol II that is catalytically inactive and heavily depends on the 30-subunit Mediator complex for its activator and basal dependent function in vitro. Here we report for the first time, the identification and the generation of a 15-subunit human Mediator complex via the novel multibac baculovirus expression system that is fully responsive to Pol II (G). Our results show complete recovery of Pol II (G) dependent transcription …