Life Sciences Commons^™

Genetic Analysis Of A Novel Ftsk Homolog, Hfka, In Streptomyces Coelicolor Development-Associated Chromosome Segregation, Sumedha Sethi

Electronic Theses and Dissertations

A quintessential phenomenon occurring during prokaryotic development is accurate segregation of the replicated genomes into the daughter cells. Key energy-dependent processes like chromosome condensation and subcellular partitioning of the genomes are driven by conserved proteins like SMC, ParB, FtsK. During its complex developmental cycle, Streptomyces coelicolor segregates its genomes into chains of unicellular spores when its multigenomic syncytial aerial hyphae undergo division.

A novel ftsK-like gene, hfkA (Homolog of FtsK protein A), was examined for function and localization during development-associated chromosome segregation. Individual deletions did not affect segregation, but a ΔhfkA ΔftsK mutant exhibited 8% anucleate …

Genetic And Biochemical Analysis Of A Conserved, Multi-Gene System Regulation Spore-Associated Proteins In Streptomyces Coelicolor, Joseph Sallmen

Electronic Theses and Dissertations

Streptomyces coelicolor is a Gram positive, filamentous soil dwelling bacterium that exhibits a complex life cycle including the transition from a vegetative mycelium to a sporulating, aerial mycelium. Early genetic studies identified two classes of genes that resulted in developmental blocks, bald and white. The bald (bld) phenotype occurs when colonies cannot produce aerial hyphae. White (whi) colonies exhibit incomplete sporulation and/or loss of production of the concurrently produced grey pigment. While some of the original mutants have been explored, the developmental functions of many of the identified genes are not well understood. Of particular interest …

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 …

Chasing The Genetics Of Ascites In Broilers Using Whole Genome Resequencing, Alia Parveen

Graduate Theses and Dissertations

We are using whole genome resequencing to identify chromosomal regions associated with resistance or susceptibility to ascites, a form of pulmonary hypertension syndrome, meat-type chickens. Previous Genome Wide Association Studies (GWAS) based on Single Nucleotide Polymorphisms (SNPs) have identified regions on chromosomes 2, 9 and Z. Despite several GWAS and further genotyping, there are no reliable or potential markers for ascites phenotype. We have completed screening of Copy Number Variations (CNVs) and Single Nucleotide Polymorphisms in ascites resistant and susceptible birds from the relaxed, REL, line derived from a commercial elite broiler line. DNA samples from resistant and susceptible birds …

Transcriptional Responses Of Soybean Aphids To Sublethal Insecticide Exposure, Laramy S. Enders, Leslie C. Rault, Tiffany Heng-Moss, Blair Siegfried, Nicholas J. Miller

Department of Entomology: Faculty Publications

Insecticides are a key tool in the management of many insect pests of agriculture, including soybean aphids. The selection imposed by insecticide use has often lead to the evolution of resistance by the target pest through enhanced detoxification mechanisms. We hypothesised that exposure of insecticide-susceptible aphids to sublethal doses of insecticides would result in the up-regulation of genes involved in detoxification of insecticides, revealing the genes upon which selection might act in the field. We used the soybean aphid biotype 1 reference genome, version 6.0 as a reference to analyze RNA-Seq data. We identified multiple genes with potential detoxification roles …

Molecular Survey Of Helminths Infecting Ground Dwelling Birds In The Grouse Subfamily Tetraoninae, Briana M. Sesmundo

Honors College Theses

Alaskan grouse and ptarmigan (Galliformes) are important avian game species in Alaska. Interestingly, gallids harbor a fairly diverse helminth fauna, particularly cestodes, which may make birds with high parasite loads more susceptible to predation. Unfortunately, there is limited information available on the helminth fauna of Alaskan gallids, and no molecular surveys. The present study aims to develop baseline data on diversity of intestinal and subcutaneous (filariid) helminth infections in galliforms using morphological and molecular (DNA) approaches. These data can then be used to better understand changes in helminth community structure given current environmental volatility. The intestines, cloaca, liver and kidneys …

Evolutionary Genetics Of The Genus Zamia (Zamiaceae, Cycadales), Michael Calonje

FIU Electronic Theses and Dissertations

The genus Zamia L. (Zamiaceae), consisting of 77 species, is the most species-rich and widely distributed cycad genus in the New World and is arguably the most morphologically and ecologically diverse genus in the Cycadales. We utilized a multilocus sequence dataset of 10 independent loci (9 single copy nuclear genes + 1 plastid) and extensive taxon sampling (over 90% of species) to infer phylogenetic relationships within Zamia. We infer a robust phylogenetic tree for the genus with a strong geographic delimitation of clades and find that four morphological characters typically used for diagnostic purposes in the genus exhibit a high …

Pot1 Proteins In Green Algae And Land Plants: Dna-Binding Properties And Evidence Of Co-Evolution With Telomeric Dna, Eugene V. Shakirov, Xiangyu Song, Jessica A. Joseph, Dorothy E. Shippen

Yevgeniy (Eugene) Shakirov

Telomeric DNA terminates with a single-stranded 3′ G-overhang that in vertebrates and fission yeast is bound by POT1 (Protection Of Telomeres). However, no in vitro telomeric DNA binding is associated with Arabidopsis POT1 paralogs. To further investigate POT1–DNA interaction in plants, we cloned POT1 genes from 11 plant species representing major branches of plant kingdom. Telomeric DNA binding was associated with POT1 proteins from the green alga Ostreococcus lucimarinus and two flowering plants, maize and Asparagus. Site-directed mutagenesis revealed that several residues critical for telomeric DNA recognition in vertebrates are functionally conserved in plant POT1 proteins. However, the plant proteins …

Heterologous Expression Of Pantoea Agglomerans Phytase Gene Optimized For Plant-Host Expression, N. N. Khabipova, L. R. Valeeva, I. B. Chastukhina, M. R. Sharipova, Eugene V. Shakirov

Yevgeniy (Eugene) Shakirov

Here we report expression and characterization of recombinant bacterial phytase PaPhyC from Pantoea sp. Codon-optimized phytase gene was expressed E.coli BL21 pLysS and protein expression was confirmed by Western blotting. Recombinant protein expressed in E.coli has high phytase activity. We show that PaPhyC recombinant phytase has different molecular masses when expressed in bacteria and plants, suggesting that possible protein glycosylation in plants may influence its overall size.

Sumoylation, Oliver Kerscher

Oliver Kerscher

Eukaryotic cells utilise the dynamic addition and removal of SUMO, a small ubiquitin‐like modifier (UBL), to modulate protein functions, interactions and localisation. Protein SUMOylation involves a cascade of dedicated enzymes that facilitate the covalent modification of specific lysine residues on target proteins with monomers or polymers of SUMO. The cellular homeostasis of SUMOylated proteins is also regulated by SUMO proteases and SUMO‐targeted ubiquitin ligase (STUbLs). SUMO proteases cleave SUMO from modified proteins. In contrast, STUbLs ubiquitinate proteins modified with SUMO chains. Recent data suggests that ubiquitination via STUbLs effects the turnover of SUMOylated proteins as well as the spatio‐temporal composition …

Sumo-Targeted Ubiquitin Ligase (Stubl) Slx5 Regulates Proteolysis Of Centromeric Histone H3 Variant Cse4 And Prevents Its Mislocalization To Euchromatin, Kentaro Ohkuni, Yoshimitsu Takahashi, Alyona Fulp, Oliver Kerscher

Oliver Kerscher

Centromeric histone H3, CENP-ACse4, is essential for faithful chromosome segregation. Stringent regulation of cellular levels of CENP-ACse4 restricts its localization to centromeres. Mislocalization of CENP-ACse4 is associated with aneuploidy in yeast and flies and tumorigenesis in human cells; thus defining pathways that regulate CENP-A levels is critical for understanding how mislocalization of CENP-A contributes to aneuploidy in human cancers. Previous work in budding yeast shows that ubiquitination of overexpressed Cse4 by Psh1, an E3 ligase, partially contributes to proteolysis of Cse4. Here we provide the first evidence that Cse4 is sumoylated by E3 ligases Siz1 and Siz2 in vivo and …

Sumo-Targeted Ubiquitin Ligases (Stubls) Reduce The Toxicity And Abnormal Transcriptional Activity Associated With A Mutant, Aggregation-Prone Fragment Of Huntingtin, Kentaro Ohkuni, Nagesh Pasupala, Jennifer Peek, Oliver Kerscher

Oliver Kerscher

Cell viability and gene expression profiles are altered in cellular models of neurodegenerative disorders such as Huntington’s Disease (HD). Using the yeast model system, we show that the SUMO-targeted ubiquitin ligase (STUbL) Slx5 reduces the toxicity and abnormal transcriptional activity associated with a mutant, aggregation-prone fragment of huntingtin (Htt), the causative agent of HD. We demonstrate that expression of an aggregation-prone Htt construct with 103 glutamine residues (103Q), but not the non-expanded form (25Q), results in severe growth defects in slx5Δ and slx8Δ cells. Since Slx5 is a nuclear protein and because Htt expression affects gene transcription, we …

Sumo Targeting Of A Stress-Tolerant Ulp1 Sumo Protease, Jennifer Peek, Catherine Harvey, Dreux Gray, Oliver Kerscher

Oliver Kerscher

SUMO proteases of the SENP/Ulp family are master regulators of both sumoylation and desumoylation and regulate SUMO homeostasis in eukaryotic cells. SUMO conjugates rapidly increase in response to cellular stress, including nutrient starvation, hypoxia, osmotic stress, DNA damage, heat shock, and other proteotoxic stressors. Nevertheless, little is known about the regulation and targeting of SUMO proteases during stress. To this end we have undertaken a detailed comparison of the SUMO-binding activity of the budding yeast protein Ulp1 (ScUlp1) and its ortholog in the thermotolerant yeast Kluyveromyces marxianus, KmUlp1. We find that the catalytic UD domains of both ScUlp1 and …

Nitric Oxide Is Involved In Heavy Ion-Induced Non-Targeted Effects In Human Fibroblasts, Megumi Hada, Premkumar B. Saganti, Francis A. Cucinotta

Health Physics & Diagnostic Sciences Faculty Publications

Previously, we investigated the dose response for chromosomal aberration (CA) for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) particles, and showed that the dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Our results suggested that the simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. Nitric oxide (NO) has been reported as a candidate for intercellular signaling for NTE in many studies. In order to estimate the …

Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver

Electronic Theses, Projects, and Dissertations

Rhinichthys osculus (Cyprinidae), the speckled dace, is the most widely distributed freshwater fish in the western United States. The southern California populations of R. osculus are identified as the Santa Ana speckled dace (SASD), though the SASD has not yet been formally recognized as a distinct taxon. Current mtDNA analysis performed in the Metcalf Lab has shown a reciprocally monophyletic relationship among three California regions; southern, central coast, and Owens Valley. Similarly, microsatellite genotyping has shown significant levels of geographic population structure. The purpose of this study was to provide nuclear DNA sequence data to determine the taxonomic status of …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

Chitosan As An Immune Modulator: Therapeutic Potential In Cerebral Amyloidopathies, Tanya Larissa Cupino

Loma Linda University Electronic Theses, Dissertations & Projects

Alzheimer’s disease (AD) and cerebral amyloid angiopathy (CAA) are neurodegenerative diseases that are pathologically defined by accumulations of amyloid beta (Aβ) in the brain parenchyma and vascular walls, respectively. CAA comorbidity occurs in more than half of advanced AD cases. Aβ can activate complement, an enzymatic cascade that terminates in a cytolytic pore called membrane attack complex (MAC). Protectin (CD59) is a GPI-anchored glycoprotein that physically interrupts formation of MAC. At autopsy, individuals with AD and CAA have high levels of MAC and normal to low levels of CD59 in the tunica media of affected blood vessels. We proposed the …

Total Rna Extraction From Transgenic Flies Misexpressing Foreign Genes To Perform Next Generation Rna Sequencing, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Due to absence of transgenic approaches in Notopthalmus Viridescens (newt), and conservation of genetic machinery across species, we generated transgenic Drosophila melanogaster to misexpress unique genes from newt. Novel newt genes cloned, and inserted at attP site in Drosophila were misexpressed ubiquitously using tubulin Gal-4. Sample (total RNA) for RNA sequencing was collected at 3rd instar larval stage during which major developmental events takes place in Drosophila. Total RNA was extracted, and purified using RNA clean and ConcentratorTM. RNA quality was quantitated by calculating absorbance at 260 nm (A260) and 280 nm (A280) wavelengths using Nanodrop 2000 spectrophotometer. Good quality …

The Dispersal Pattern Of Thekopsora Minima In Wild Blueberry Determined By A Molecular Detection Method, Nghi Nguyen

Electronic Theses and Dissertations

Blueberry rust caused by Thekopsora minima is a common disease in wild blueberry (Vaccinium angustifolium) and other Vaccinium genera. Understanding the spore dispersal pattern and disease cycle of fungal pathogens in wild blueberry is crucial for the development of a more efficient disease management program. Molecular assays for rapid detection and quantification of Thekopsora minima were developed to be incorporated with a spore trap sampling method and weather data collection to examine spore dispersal pattern and production in three different fields: Blueberry Hill Farm in Jonesboro, East Machias, and Spring Pond in Deblois, Maine, in three years 2014, …

Comparative Transcriptomic Analysis And Structure Prediction Of Novel Newt Proteins, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Notophthalmus viridescens (Red-spotted Newt) possess amazing capabilities to regenerate their organs and other tissues. Previously, using a de novo assembly of the newt transcriptome combined with proteomic validation, our group identified a novel family of five protein members expressed in adult tissues during regeneration in Notophthalmus viridescens. The presence of a putative signal peptide suggests that all these proteins are secretory in nature. Here we employed iterative threading assembly refinement (I-TASSER) server to generate three-dimensional structure of these novel Newt proteins and predicted their function. Our data suggests that these proteins could act as ion transporters, and be involved …

Determining The Functions Of Novel Genes Required For Photosynthesis, Gillian Gomer, Moshe Kafri, Martin Jonikas

Gillian Gomer

Assessing The Efficacy Of Seedling Planting As A Forest Restoration Technique In Temperate Hardwood Forests Impacted By Invasive Species, Michaela J. Woods, Meredith Cobb, Katie Hickle

Biology Faculty Publications

The emerald ash borer (Agrilus planipennis Fairmaire; EAB) is an invasive insect that causes mortality of trees in the genus Fraxinus, creating canopy gaps that may facilitate invasion by exotic plants. Planting native tree seedlings under EAB-infested Fraxinus may accelerate succession and preclude invasive plant expansion; however, the effectiveness of this approach has not been experimentally tested. We assessed understory seedling planting of Quercus rubra, Carya laciniosa, and Juglans cinerea in EAB-infested forests, where the invasive shrub Lonicera maackii (Amur honeysuckle) was removed. We tested whether the use of plastic tree shelters (“tree tubes”) or planting season (fall versus spring) …

P53r245w Mutation Elicits Metastatic Phenotype In Pten Deficient Prostate Cancer, Ky Pham

Dissertations & Theses (Open Access)

Trp53 mutations are the most frequent genetic alterations in prostate cancer and are associated with more aggressive disease and worse overall survival. The majority of Trp53 mutations in prostate cancer are missense mutations, resulting in amino acid substitutions with profound effect. In addition to the loss of wild type function, missense mutations in Trp53 result in a gain-of-function (GOF) phenotype. This GOF phenotype confers biologic advantages to the tumor cells, enabling them to metastasize and invade distant organs. In this study, we generated mice carrying a conditional prostate-specific p53R245W mutant and Pten deletion to access the role of this common …

Sequence Analysis Of The Ren1 Genomic Region From The Grapevine ‘Kishmish Vatkana’, Dani Joseph

MSU Graduate Theses

The REN1 region of the grapevine ‘Kishmish Vatkana’ was mapped as the locus that confers resistance to the economically important disease, grape powdery mildew. The purpose of this work was to extend the nucleotide sequence information of this region. By sequencing a heretofore unknown bacterial artificial chromosome clone, the sequence information of this region was extended by 46,890 nucleotides. Sequencing was performed using the third-generation sequencing method, named Oxford Nanopore Technology (ONT). In order to improve the accuracy of the sequence data, a modified ONT library preparation method was developed. ONT sequencing of a library prepared with the modified protocol …

Elucidating Immune Signaling Of Influenza A Virus And Aspergillus Fumigatus Co-Infections Through Pioneered Model Development, Meagan Danyelle Rippee-Brooks

MSU Graduate Theses

Bacterial co-infections with influenza A virus (IAV) are extremely serious and life-threatening. However, there exists limited understanding about the importance of fungal infections with IAV. Clinical case reports indicate that fungal co-infections do occur and suggest the IAV pandemic of 2009 had a propensity to predispose patients to secondary fungal infections more than previous IAV strains. IAV-fungal co-infections are marked by high mortality rates of 47 to 61% in previously healthy individuals between the ages of 20 and 60. Yet, the variables involved in this co-infection remain undetermined. I achieved effective recapitulation of this co-infection using a C57Bl/6 murine (mouse) …

Cd21 And Cd24 Co-Expression: A Translational Model Between Mouse And Human, Abigail Benitez

Abigail Benitez, PhD

Systemic Lupus Erythematosus and Rheumatoid Arthritis are B cell-mediated autoimmune diseases that afflict millions of people worldwide. B cell-targeted therapies for these diseases result in variable clinical outcomes. Thus, a need exists to better understand the dynamics of human B cell production and function. The mouse model has provided a foundation for understanding the mechanisms involved in human B cell development and autoimmune disease. However, differences in mouse and human B cells are not fully understood. Our work shows that the co-expression of CD21 and CD24, determined by 7-color flow cytometry, can be used to demarcate developmental subsets of B …

Emergence Of Oxacillin Resistance In Stealth Methicillin-Resistant Staphylococcus Aureus Due To Meca Sequence Instability, Richard V. Goering, Erin A. Swartzendriber, Anne E. Obradovich, Isabella A. Tickler, Fred C. Tenover

Biology Faculty Publications

Staphylococcus aureus strains that possess a mecA gene but are phenotypically susceptible to oxacillin and cefoxitin (OS-MRSA) have been recognized for over a decade and are a challenge for diagnostic laboratories. The mechanisms underlying the discrepancy vary from isolate to isolate. We characterized seven OS-MRSA clinical isolates of six different spa types from six different states by whole-genome sequencing to identify the nucleotide sequence changes leading to the OS-MRSA phenotype. The results demonstrated that oxacillin susceptibility was associated with mutations in regions of nucleotide repeats within mecA. Subinhibitory antibiotic exposure selected for secondary mecA mutations that restored oxacillin resistance. …

Determining The Functions Of Novel Genes Required For Photosynthesis, Gillian Gomer, Moshe Kafri, Martin Jonikas

Gillian Gomer

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella

Biology ETDs

At high latitudes, climatic oscillations have triggered repeated episodes of organismal divergence by geographically isolating populations. For terrestrial species, extended isolation in glacial refugia – ice-free regions that enable terrestrial species persistence through glacial maxima – is hypothesized to stimulate allopatric divergence. Alternatively, upon glacial recession, divergent populations expanded from independent glacial refugia and often contacted other diverging populations. In the absence of reproductive isolating mechanisms, this biogeographic process may trigger hybridization and ultimately, gene flow between divergent taxa. My dissertation research aims to understand how these episodic periods of isolation and contact have impacted the evolution of high latitude …

Identifying Brachypodium Distachyon Proteins Interacting With Histone Deacetylase Bdhd1, Alberto Giovanni Torrez

Electronic Thesis and Dissertation Repository

Current evidence has revealed the involvement of epigenetic mechanisms, including histone deacetylases (HDACs), in plant stress responses. In Arabidopsis thaliana, HDA19, belonging to the RPD3/HDA1 class, interacts with transcription factors to form repressor complexes. HDAC research mainly exists for dicotyledons, whereas research on monocotyledons is limited. Brachypodium distachyon is used as a model plant to investigate questions unique to monocot crops. BdHD1 is the closest homologous gene to HDA19 in B. distachyon. This study investigated potential protein-protein interactions between BdHD1 and each of BdMYB22, BdWRKY24, and BdHOS15. Protein interactions were investigated using yeast two-hybrid (Y2H) and bimolecular fluorescence …

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