Life Sciences Commons^™

From Regulation Of Secondary Metabolites To Increased Virulence Under Sublethal Dosage Of Antibiotics: An Unprecedented Role Of Global Regulator, Mftr, In Burkholderia Thailandensis, Sudarshan Singh Thapa

LSU Doctoral Dissertations

The rise of multi-drug resistant bacteria combined with a decreasing pool of effective antibiotics has placed an increasing need for the development of novel antibiotics. Bacterial natural products or secondary metabolites have been the greatest source for development of novel antibiotics. The genus Burkholderia has recently emerged as a source of promising compounds with antibacterial, antifungal, and anti-cancer activities. Bacterial secondary metabolites provide added advantage to bacteria under stressful environments such as during host infection, evading predators or nutrient deficient conditions. However, genes involved in synthesis of these novel compounds remain silent under normal laboratory growth, creating a hurdle in …

Electronic-Cigarette Vehicles And Flavoring Affect Lung Function And Immune Responses In A Murine Model, Brittany N. Szafran, Rakeysha Pinkston, Zakia Perveen, Matthew K. Ross, Timothy Morgan, Daniel B. Paulsen, Arthur L. Penn, Barbara L. F. Kaplan, Alexandra Noel

Faculty Publications

The use of electronic nicotine delivery systems (ENDS), also known as electronic-cigarettes (e-cigs), has raised serious public health concerns, especially in light of the 2019 outbreak of e-cig or vaping product use-associated acute lung injury (EVALI). While these cases have mostly been linked to ENDS that contain vitamin E acetate, there is limited research that has focused on the chronic pulmonary effects of the delivery vehicles (i.e., without nicotine and flavoring). Thus, we investigated lung function and immune responses in a mouse model following exposure to the nearly ubiquitous e-cig delivery vehicles, vegetable glycerin (VG) and propylene glycol (PG), used …

Comparative Transcriptomics Of Rice Genotypes With Contrasting Responses To Nitrogen Stress Reveals Genes Influencing Nitrogen Uptake Through The Regulation Of Root Architecture, Prasanta K. Subudhi, Richard S. Garcia, Sapphire Coronejo, Ronald Tapia

Faculty Publications

The indiscriminate use of nitrogenous fertilizers continues unabated for commercial crop production, resulting in air and water pollution. The development of rice varieties with enhanced nitrogen use efficiency (NUE) will require a thorough understanding of the molecular basis of a plant's response to low nitrogen (N) availability. The global expression profiles of root tissues collected from low and high N treatments at different time points in two rice genotypes, Pokkali and Bengal, with contrasting responses to N stress and contrasting root architectures were examined. Overall, the number of differentially expressed genes (DEGs) in Pokkali (indica) was higher than in Bengal …

Insights Into Desiccation Tolerance: Properties Of Late Embryogenesis Abundant Proteins From Embryos Of Artemia Franciscana, Blase Matthew Leblanc

LSU Doctoral Dissertations

LEA proteins are a family of intrinsically disordered proteins that are expressed in various life stages of anhydrobiotic organisms and have been strongly associated with survival during water stress. The brine shrimp Artemia franciscana is the only known anhydrobiotic animal that expresses LEA proteins from Groups 1, 3, and 6. Here, I report that AfrLEA6, a novel Group 6 LEA protein, is most highly expressed in embryos during diapause and decreases throughout pre-emergence development. Notably, there is an acute drop in expression upon termination of the diapause state and the titer of AfrLEA6 during diapause is 10-fold lower than values …

Evidence Of Pathogen-Induced Immunogenetic Selection Across The Large Geographic Range Of A Wild Seabird, Hila Levy, Stephen R. Fiddaman, Julianna A. Vianna, Daly Noll, Gemma Clucas, Jasmine K. H. Sidhu, Michael J. Polito, Charles A. Bost, Richard A. Phillips, Sarah Crofts, Gary D. Miller, Pierre Pistorius, Francesco Bonnadonna, Celine Le Bohec, Andres Barbosa, Phil Trathan, Andrea Raya Rey, Laurent A. F. Frantz, Tom Hart, Adrian L. Smith

Faculty Publications

Over evolutionary time, pathogen challenge shapes the immunepheno type of the host to better respond to an incipient threat. The extent and direction of this selection pressure depend on the local pathogen composition, which is in turn determined by biotic and abiotic features of the environment. However, little is known about adaptation to local pathogen threats in wild animals. The Gentoo penguin (Pygoscelis papua) is a species complex that lends itself to the study of immune adaptation because of its circumpolar distribution over a large latitudinal range, with little or no admixture between ''different clades. Inthis study, we examine the …

Characterization Of Drosophila Boundary Element Associated Factor Beaf-32b Interactions With Transcription Factors And Chromatin Remodeling Complexes., Yuankai Dong

LSU Doctoral Dissertations

BEAF (Boundary Element-Associated Factor) was originally identified as a chromatin domain insulator binding protein, suggesting that it might play a role in linking gene regulation to chromatin organization and dynamics. Genome-wide mapping found that BEAF is usually found near transcription start sites, often of housekeeping genes, suggesting that it might play a role in promoter function. This would be a nontraditional role for an insulator binding protein. To gain insight into molecular mechanisms of BEAF function, we identified proteins that interact with BEAF using yeast 2-hybrid assays. Here we focus on three identified transcription factors: Bcd, Scr and Sry-δ. Interactions …

The Effects Of Transgenic Alterations Of Bicarbonate-Utilizing Enzymes In Escherichia Coli On The Activity Of Acetyl-Coa Carboxylase, Aniko Alicia Nowakowski

Honors Theses

No abstract provided.

Understanding How Human Lipoxygenases Bind Molecular Oxygen And Arachidonic Acid Substrate, Austin Paul Primeaux

Honors Theses

No abstract provided.

Functions Of Cdk/Cyclin Complexes In Endoreplication Regulation By The Cdk Inhibitor Siamese, Kai Wang

LSU Doctoral Dissertations

Arabidopsis trichome (leaf hair) is a specialized single cell extended from epidermal cell on the leaves, which is a typical endoreplication and is also known as endoreduplication. Several D-type cyclins were tested to check the cell division in trichome, and the trichome expressing either CYCB1;2 or CDKB2;2 cannot trigger cell division, even if simultaneous expression of CYCB1;2 and CDKB2;2 failed to produce mitosis in trichome. Only CYCD3;1 specifically promotes multicellular trichome. cdkb1;1cdbk1;2 double mutants and sim cdkb1;1cdkb1;2 triple mutants exhibit the phenotype similar to the wild type and very limited cell division respectively. Overexpression of a CDKB1;1 dominant-negative construct that …

Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan

LSU Doctoral Dissertations

The impacts of sea-level rise and hydrologic manipulation are threatening the stability of coastal marshes throughout the world, thereby increasing the potential for re-mineralization of soil organic matter (SOM) in these systems. Such threats have prompted marsh restoration efforts, particularly in coastal Louisiana, yet it is unclear how the slowly decomposing (refractory) and quickly decomposing (labile) fractions of SOM may be differentially affected by different approaches to marsh restoration. Additionally, otherwise labile compounds may accumulate in the soil via a range of protective mechanisms, including rapid burial and association with organic compounds that are thought to enhance soil aggregation, such …

Synthesis And Preliminary Ex Vivo Testing Of Sirna Targeting Tcrb: A Proposed Therapy For The Treatment Of Autoimmunity, Nicholas J. Magazine

LSU Doctoral Dissertations

Abstract

Background:

As of 2018, the United States National Institutes of Health estimate that over half a billion people worldwide are affected by autoimmune disorders. Though these conditions are prevalent, treatment options remain relatively poor, relying primarily on various forms of immunosuppression which carry potentially severe side effects and often lose effectiveness overtime. Given this, new forms of therapy are needed. We propose small-interfering RNA (siRNA) for hypervariable regions of the T-cell receptor β-chain gene (TCRb) as a highly targeted, novel means of therapy for the treatment of autoimmune disorders.

Objectives:

To develop methods to produce siRNA targeting …