Other Genetics and Genomics Commons^™

Homocysteine Thiolactone From Translation Proofreading Is An Endogenous Ligand For Cell-Cell Signaling By The Receptor Sdia, Lorenzo Eugenio Leiva, Roberto A. Zúñiga, Gregory J. Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Several widespread mechanisms enable cellular communication and coordinate the behavior of bacterial populations. The modules responsible for cellular communication are often found in matching pairs: an enzyme that synthesizes a signal molecule and a specific receptor that decodes it. A notable exception is Escherichia coli SdiA, a homolog of known N-acyl-homoserine lactone (AHL) receptors, for which no corresponding AHL synthase exists. SdiA is an orphan receptor that enables cross-talk by sensing AHLs from other bacterial species. In this work, we investigated whether homocysteine thiolactone (HTL), an AHL-like molecule arising from a proofreading reaction of methionyl tRNA synthetase (MetRS) to correct …

Effects Of M6a Dna Methylation By Bacterial Methyltransferase In Colorectal Cancer, Fabian Alejandro Mendoza Galvan

Dissertations and Theses (Open Access)

Effects of m6A DNA methylation by bacterial methyltransferase in colorectal cancer Fabian Alejandro Mendoza Galvan Advisory Professor: Angela H. Ting, Ph.D. Fusobacterium nucleatum animalis (Fna) is found in the human oral cavity and gut. A distinct clade of Fna is primarily enriched in the tumor microenvironment (TME) and within colorectal cancer (CRC) cells. This clade DNA methylation pattern is primarily catalyzed by a cell-cycle regulated methyltransferase (CcrM) ortholog, M.FnI, that targets the GANTC sequence motif through methyl-6-Adenine (m6A) DNA methylation. We hypothesized that M.FnI enzyme can induce m6A methylation abnormalities in CRC cells to promote cancer progression. Evidence for endogenous …

Reverse Micelles Produce Hydroxyapatite Nanoparticles As More Efficient Gene Delivery Carriers Than Regular Micelles, Vuk Uskoković

Administration and Staff Articles and Research

Hydroxyapatite (HAp) is an effective inorganic gene delivery carrier due to its ability to transport genetic cargo across cell membranes, protect it from proteolysis, and enable escape from late endosomes via pH-controlled dissolution. However, its transfection efficiency remains lower than that of viral agents, prompting studies of hybrids with cationic molecules or phases to enhance the gene delivery performance. This study reports on the synthesis of HAp in regular and reverse micellar regions of a ternary microemulsion system composed of cetyltrimethylammonium bromide (CTAB), 1-hexanol and water. Spectroscopic characterization revealed that CTAB headgroups adopted more ordered supramolecular conformations in reverse micelles …

A Framework For Characterizing The Peripheral Immune Isonome Using Long-Read Single-Cell Rna Sequencing And Its Relevance To Neurological Disease, Patricia Hayes Doyle

Theses and Dissertations--Neuroscience

Long-read single-cell RNA sequencing provides an opportunity to understand human health and disease at isoform resolution, revealing cellular diversity and disease mechanisms difficult to resolve with bulk or short-read methodologies.

Using a modified PIPseq workflow and computational pipeline adapted for Oxford Nanopore (ONT) sequencing, we profiled isoform usage across immune cells, integrating marker expression and isoform discovery, generating the largest long-read single-cell dataset of human immune cells from a single individual to date. We identified non-canonical protein-coding variants of GZMB and CD3G enriched in unexpected cell types. We also discovered novel transcripts from CMC1 and LYAR with cell-type-specific signatures that …

Development Of Self-Assembled Polymeric Polyplexes For Microrna Delivery: Toward Treatment Of Alcohol-Associated Liver Disease, Marjina Akter Kalpana

Theses & Dissertations

Self-assembled polymeric polyplexes have the potential to serve as an RNA interference (RNAi) delivery platform for the combined inhibition of CXCR4 and miR-155 in the treatment of alcohol-associated liver disease (AALD). A central challenge in RNA delivery is balancing the extracellular stability of polyplexes, cellular uptake, and intracellular release of RNA cargo. We developed polymeric polyplexes using the CXCR4-antagonist polymer PAMD, designed to target CXCR4 on activated hepatic stellate cells (HSCs) and deliver therapeutic miRNA to activated Kupffer cells (KCs) in fibrotic liver. We improved the polyplexes by cholesterol modification of PAMD and by PEGylation of PAMD-Ch. The cholesterol modification …

Omani Camels From A Cultural And Genomics Perspective, Al Muatasim Al Zadjali

Electronic Theses and Dissertations

The Dromedarian camel, Camelus dromedarius, is native to the Arabian Peninsula, including the Sultanate of Oman. These camels are used for food, milk, as well as show and racing competitions. Despite their economic and cultural importance research on camels in Oman is limited. The goal of this study was to examine their genomic variation, relationship with camels in other parts of the Arabian Peninsula, and to determine if selective breeding has led to the establishment of distinct breeds in Oman. Information was compiled from multiple sources to produce a comprehensive review on the breeding, management, economic and cultural use, …

Identifying Functional Enhancers For Fibrotic Gene Regulation In Liver Fibrosis, Parnaz Merikhian

Dissertations and Theses (Open Access)

Liver fibrosis is characterized by progressive activation of proliferating and migrating myofibroblasts that lead to accumulation of extracellular matrix (ECM). These myofibroblasts most arise from activated liver-resident hepatic stellate cells (HSCs). There is an increasing number of patients suffering from liver fibrosis in developed countries including the United States, which is anticipated to continue to grow during 2023-2033 period. TGF-β1 is a key cytokine with a significant role in regulating cell differentiation and adhesion in liver fibrosis. TGF-β signaling triggers gene expression changes in HSCs, including that of fibrotic and EMT-related genes, which then functionally promote HSCs activation and fibrogenesis. …

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.

Roles Of Oxidative Stress And Dna Methylation In Cigarette Smoking-Induced Accelerated Acute Myeloid Leukemia Progression, Mary Figueroa

Dissertations and Theses (Open Access)

Acute myeloid leukemia (AML) is a commonly diagnosed cancer in smokers. When current or former smokers have AML, they have worse survival compared to never smoking patients. This has been observed clinically for decades, but then it is unknown how smoking leads to worsened AML survival. Smoking causes oxidative stress and altered DNA methylation that persists for decades in peripheral blood mononuclear cells, but these changes from smoking have not been evaluated in the context of AML. We hypothesize that smoking-induced molecular changes, including altered DNA methylation associated with poor AML prognosis, promote AML. We developed a novel model to …

Induction Of Il19 Expression Through Jnk And Cgas-Sting Modulates Dna Damage–Induced Cytokine Production, Sara H. Small, E. Jessica Tang, Ryan L. Ragland, Yaroslava Ruzankina, David W. Schoppy, Rahul S. Mandal, M. Rebecca Glineburg, Zgjim Ustelenca, Daniel J. Powell, Fiona Simpkins, F. Bradley Johnson, Eric J. Brown

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Cytokine production is a critical component of cell-extrinsic responses to DNA damage and cellular senescence. Here, we demonstrated that expression of the gene encoding interleukin-19 (IL-19) was enhanced by DNA damage through pathways mediated by c-Jun amino-terminal kinase (JNK) and cGAS-STING and that IL19 expression was required for the subsequent production of the cytokines IL-1, IL-6, and IL-8. IL19 expression was stimulated by diverse cellular stresses, including inhibition of the DNA replication checkpoint kinase ATR (ataxia telangiectasia and Rad3-related protein), oncogene expression, replicative exhaustion, oxidative stress, and DNA double-strand breaks. Unlike the production of IL-6 and IL-8, IL19 expression was …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

University Scholar Projects

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

Honors Scholar Theses

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

Enhanced Detection Of Expanded Repeat Mrna Foci With Hybridization Chain Reaction, M. Rebecca Glineburg, Yuan Zhang, Amy Krans, Elizabeth M. Tank, Sami J. Barmada, Peter K. Todd

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Transcribed nucleotide repeat expansions form detectable RNA foci in patient cells that contribute to disease pathogenesis. The most widely used method for detecting RNA foci, fluorescence in situ hybridization (FISH), is powerful but can suffer from issues related to signal above background. Here we developed a repeat-specific form of hybridization chain reaction (R-HCR) as an alternative method for detection of repeat RNA foci in two neurodegenerative disorders: C9orf72 associated ALS and frontotemporal dementia (C9 ALS/FTD) and Fragile X-associated tremor/ataxia syndrome. R-HCR to both G₄C₂ and CGG repeats exhibited comparable specificity but > 40 × sensitivity compared to FISH, …

Artificial Intron Technology To Generate Conditional Knock-Out Mice, Amber N. Thomas-Gordon

Dissertations and Theses (Open Access)

Genetic engineering has been re-shaped by the invention of new tools in modern biotechnology in a way that offers precision and efficiency in modifying the genome at a single nucleotide level and/or allowing precise control of gene expression. Such gene manipulation brings about significant findings and revelations in comprehending more about embryonic development, cellular and physiological functions, and disease pathology. Current methods used to produce conditional knockouts have limitations on conditional allele placement and modification varies among genes in different organisms. Thus, a system for generating conditional alleles with fidelity remains a challenge. My goal was to examine an approach …

Analyzing The Effect On Ligand Sensitivity For Xenopus Tropicalis Mc1r, Mc3r, Mc4r, And Mc5r As A Result Of Coexpression With Gallus Gallus Mrap1 In Chinese Hamster Ovary Cells, Avery Niemann, Robert Dores

DU Undergraduate Research Journal Archive

Some melanocortin receptors and the accessory protein MRAP1 have been found to interact in novel ways when co-expressed in the same cells following stimulation with either ACTH (1-24) or αMSH. These interactions have been seen for mammalian, bird, and some bony fish melanocortin receptors. Such analysis has not been done yet on the amphibian melanocortin receptors, MC1R, MC3R, MC4R, and MC5R. To this end, this study was done on the effects regarding ligand sensitivity for ACTH (1-24) and αMSH, when the MC1R, MC3R, MC4R, and MC5R paralogs of the amphibian, Xenopus tropicalis were expressed in Chinese Hamster Ovary cells either …

A "Choose-Your-Own" Classroom-Based Activity That Promotes Scientific Inquiry About Rna Interference, Jeremy L. Hsu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

RNA interference (RNAi), the process that results in the degradation of a target gene’s mRNA, is a fundamental part of eukaryotic gene regulation and is also an important molecular technique that allows for experimental manipulation of gene expression without altering DNA sequences. Despite the importance of RNAi, there have been relatively few lecture-based activities designed to teach about the consequences of this process and counter common misconceptions. I present here an inquiry-based activity that is centered around a “choose your own experiment” design where students generate hypotheses and critically evaluate their ideas by choosing several simulated experiments. The activity presents …

Divergent Transcriptional Regulation Of Suppressors Of Cytokine Signaling Genes In Adipocytes, Paula Mota De Sa

LSU Doctoral Dissertations

The Janus Kinase - Signal Transducer and Activator of Transcription (JAK-STAT) signaling pathway transduces several signals crucial for development and homeostasis. Suppressors of cytokine signaling (SOCS) proteins control JAK-STAT signaling via a negative feedback loop. The transcription factor STAT5 is known to play a significant role in fat cell development and function, and several studies suggest that acetylation may affect STAT5 transcriptional activity. To test this hypothesis, we treated 3T3-L1 adipocytes with growth hormone (GH) to activate STAT5 in the presence or absence of histone deacetylase (HDAC) inhibitors. STAT5 acetylation levels were low in adipocytes and mostly unchanged by the …

Deletion Of Uls1 Confers Damage Tolerance In Sgs1 Mutants Through A Top3-Dependent D-Loop Mediated Fork Restart Pathway, M. Rebecca Glineburg, Eleanor Johns, F. Brad Johnson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Homologous recombination (HR)-based repair during DNA replication can apparently utilize several partially overlapping repair pathways in response to any given lesion. A key player in HR repair is the Sgs1-Top3-Rmi1 (STR) complex, which is critical for resolving X-shaped recombination intermediates formed following bypass of methyl methanesulfonate (MMS)-induced damage. STR mutants are also sensitive to the ribonucleotide reductase inhibitor, hydroxyurea (HU), but unlike MMS treatment, HU treatment is not accompanied by X-structure accumulation, and it is thus unclear how STR functions in this context. Here we provide evidence that HU-induced fork stalling enlists Top3 prior to recombination intermediate formation. The resistance …

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …

Exploring The Ipf Lung Through The Lens Of Single Cell Rna Sequencing, Taylor Adams, Jonas Schupp

Yale Day of Data

This poster illustrates the differences between the IPF disease-specific variety of lung macrophages and the two varieties of macrophages known to reside in the normal human lung.

Hnrnpa2 Mediated Acetylation Reduces Telomere Length In Response To Mitochondrial Dysfunction, Manti Guha, Satish Srinivasan, F. Bradley Johnson, Gordon Ruthel, Kip Guja, Miguel Garcia-Diaz, Brett A. Kaufman, M. Rebecca Glineburg, Jikang Fang, Hiroshi Nakagawa, Jeelan Basha, Tapas Kundu, Narayan G. Avadhani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Telomeres protect against chromosomal damage. Accelerated telomere loss has been associated with premature aging syndromes such as Werner’s syndrome and Dyskeratosis Congenita, while, progressive telomere loss activates a DNA damage response leading to chromosomal instability, typically observed in cancer cells and senescent cells. Therefore, identifying mechanisms of telomere length maintenance is critical for understanding human pathologies. In this paper we demonstrate that mitochondrial dysfunction plays a causal role in telomere shortening. Furthermore, hnRNPA2, a mitochondrial stress responsive lysine acetyltransferase (KAT) acetylates telomere histone H4at lysine 8 of (H4K8) and this acetylation is associated with telomere attrition. Cells containing dysfunctional mitochondria …

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Punctuated Evolution Within A Eurythermic Genus (Mesenchytraeus) Of Segmented Worms: Genetic Modification Of The Glacier Ice Worm F1f0 Atp Synthase, Shirley A. Lang

Graduate School of Biomedical Sciences Theses and Dissertations

Segmented worms (Annelida) are among the most successful animal inhabitants of extreme environments worldwide. An unusual group of Mesenchytraeus worms endemic to the Pacific Northwest of North America occupy geographically proximal ecozones ranging from low elevation temperate rainforests to high altitude glaciers. Along this altitudinal transect, Mesenchytraeus representatives from disparate habitat types were collected and subjected to deep mitochondrial and nuclear phylogenetic analyses. Evidence presented here employing modern bioinformatic analyses (i.e., maximum likelihood, Bayesian inference, multi-species coalescent) supports a Mesenchytraeus “explosion” in the upper Miocene (5-10 million years ago) that gave rise to ice, snow and terrestrial worms, derived from …

Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots

STAR Program Research Presentations

The CRISPR-Cas system is an adaptive immune system found in bacteria which helps protect against the invasion of other microorganisms. This system induces double stranded breaks at precise genomic loci (1) in which repairs are initiated and insertions of a target are completed in the process. This mechanism can be used in eukaryotic cells in combination with sgRNAs (1) as a tool for genome editing. By using this CRISPR-Cas system, in addition to the “safe harbor locus,” ROSAβ26, the incorporation of a target gene into a site that is not susceptible to gene silencing effects can be achieved through few …

Genetic Analysis Reveals A Hierarchy Of Interactions Between Polycystin-Encoding Genes And Genes Controlling Cilia Function During Left-Right Determination, Daniel T. Grimes, Jennifer L. Keynton, Maria T. Buenavista, Xingjian Jin, Saloni H. Patel, Shinohara Kyosuke, Jennifer Vibert, Debbie J. Williams, Hiroshi Hamada, Rohana Hussain, Surya M. Nauli, Dominic P. Norris

Pharmacy Faculty Articles and Research

During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven leftward fluid flow within a midline embryonic cavity called the node. This ‘nodal flow’ is detected by peripherally-located crown cells that each assemble a primary cilium which contain the putative Ca²⁺ channel PKD2. The interaction of flow and crown cell cilia promotes left side-specific expression of Nodal in the lateral plate mesoderm (LPM). Whilst the PKD2-interacting protein PKD1L1 has also been implicated in L-R patterning, the underlying mechanism by which flow is detected and the genetic relationship between Polycystin function and asymmetric gene expression remains unknown. Here, we …