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Hd2d Is A Regulator Of Abscisic Acid Responses In Arabidopsis, Joshua A. Farhi

Electronic Thesis and Dissertation Repository

Histone deacetylases have important roles in development and stress response in plants. To further investigate their function, the HD2D gene, of the plant specific HD2 family, was studied. An hd2d-1 mutant and two HD2D overexpression lines were used in this study. Germination was delayed in hd2d-1 and HD2D overexpression seeds only in the presence of ABA. HD2D was found to positively regulate the expression of members of the ABA-response pathway (ABI1, ABI5, and RD29A) leading to increased resistance to drought and salinity treatments. Furthermore, HD2D expression delayed flowering by positively regulating FLC expression. Using bimolecular fluorescence complementation, the HD2D protein …

A Unified Framework For The Prioritization Of Variants Of Uncertain Significance In Hereditary Breast And Ovarian Cancer Patients, Natasha G. Caminsky

Electronic Thesis and Dissertation Repository

A significant proportion of hereditary breast and ovarian cancer (HBOC) patients receive uninformative genetic testing results, an issue exacerbated by the overwhelming quantity of variants of uncertain significance identified. This thesis describes a framework where, aside from protein coding changes, information theory (IT)-based sequence analysis identifies and prioritizes pathogenic variants occurring within sequence elements predicted to be recognized by proteins involved in mRNA splicing, transcription, and untranslated region binding and structure. To support the utilization of IT analysis, we established IT-based variant interpretation accuracy by performing a comprehensive review of mutations altering mRNA splicing in rare and common diseases.

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Characterization Of The Atsr/Atst Global Regulatory Pathway In Burkholderia Ceocepacia, Maryam Khodai-Kalaki

Electronic Thesis and Dissertation Repository

Phosphorylation cascades governed by two-component signal transduction systems provide key signalling mechanisms in bacteria, simple eukaryotes and higher plants, allowing them to translate signals into adaptive responses. These regulatory pathways consist of a transmembrane sensor protein that responds to an environmental cue leading to autophosphorylation, followed by the transfer of the phosphate to a cytoplasmic response regulator. Here, I study AtsR, a membrane-bound hybrid sensor kinase of Burkholderia cenocepacia, that negatively regulates quorum sensing related virulence factors such as biofilm, type 6-secretion and protease secretion. B. cenocepacia is a Gram-negative opportunistic pathogen which causes severe, chronic respiratory infections in …

Determination Of The Phylogenetic Range Of Sex Combs Reduced Activity In Drosophila Melanogaster, Laura E. Garofalo

Electronic Thesis and Dissertation Repository

The homeotic selector (Hox) genes are required for body patterning in bilaterians. Sex combs reduced (SCR) is a HOX protein in Drosophila melanogaster with two activities: SCR^T1 and SCR^lab activity required for patterning the prothorax (T1) and labia, respectively. SCR^T1 is proposed to be conserved throughout bilaterians while the phylogenetic range of functional conservation of SCR^lab is comparatively unknown. The goal of this work was to elucidate the evolutionary time point at which SCR activity changed. CRISPR/Cas9 transgenesis was used to incorporate ɸC31 integrase recombination sites in Drosophila Scr. The ɸC31 integrase could …

Genetic Analysis Of A Non-Germinating Mutant Of Arabidopsis Thaliana, Md Jakir Hossan

Electronic Thesis and Dissertation Repository

Seed germination is partially controlled by plant hormone gibberellins (GAs). Chemical mutagenesis yielded an Arabidopsis thaliana mutant gm11, which has an absolute gibberellin requirement for seed germination. This mutant exhibited phenotypes of GA-rescuable dwarfs, including dark-green leaves, and reduced fertility. However, with repeated GA treatment, gm11 develops into fertile plants with a nearly wild type phenotype. Bulked-segregant analysis mapped gm11 to the bottom arm of chromosome 1, and subsequent next-generation mapping revealed that the mutation is a G → A transition in At1g79460 (GA2), creating a premature stop codon. This gene encodes an ent-kaurene synthase (KS) which catalyzes …

Assessment Of Genome-Wide Genetic And Epigenetic De Novo Variation In Families With Monozygotic Twins Discordant For Schizophrenia, Christina A. Castellani

Electronic Thesis and Dissertation Repository

Schizophrenia (OMIM: 181500) is a common, debilitating and life-altering disorder. It affects 1% of the population worldwide and most often presents in early adulthood leading to devastating effects for patients, their families and society. Despite thousands of studies performed on the underlying mechanisms of schizophrenia, the causes of the disease remain unknown. However, what is known is that environmental, genetic and epigenetic factors contribute to the development of this complex disorder. Although a genetic role in schizophrenia is well established, the search for schizophrenia genes using traditional approaches has remained challenging. Interestingly, monozygotic twins show concordance for schizophrenia only 50% …

Mir156 Participates In Iron Homeostasis Through Targeting Spl9/Spl15 In Arabidopsis Thaliana, Ying Wang

Electronic Thesis and Dissertation Repository

Plants growing under iron deficiency suffer from multiple physiological defects. Although the effects of microRNA156 (miR156) on multiple aspects of plant development have been investigated, a possible role of miR156 in plant iron homeostasis has not been shown. By employing next-generation RNA-sequencing, the current research demonstrated that multiple iron homeostasis-related genes, including ones coding for Ferritins, group Ib bHLH transcription factors, and key enzymes involved in iron uptake, were differentially expressed in Arabidopsis thaliana plants overexpressing miR156. Overexpression of miR156 also enhanced Arabidopsis growth under iron-deficiency. In addition, expression analysis revealed that miR156 is a positive regulator of FIT and …

The E26 Transformation-Specific Transcription Factors Pu.1, Spi-B, And Spi-C Regulate Transcriptional Activation And Repression Of Nfkb1 To Control B Cell Development And Function, Stephen Ka Ho Li

Electronic Thesis and Dissertation Repository

PU.1, Spi-B, and Spi-C are highly related E26 transformation-specific family transcription factors that can bind nearly identical DNA sequences. PU.1 and Spi-B (encoded by Spi1 and Spib respectively) are important for B cell development and function, but the function of Spi-C (encoded by Spic) in B cells is not clear. The objective of this study was to determine PU.1, Spi-B, and Spi-C’s function during B cell development, and during TLR-mediated responses. It was hypothesized that PU.1 and Spi-B were required for positively regulating components of TLR responses, and Spi-C inhibited PU.1 and Spi-B targets. Spi1^+/-Spib^-/- ( …

Soybean Isoflavonoid Biosynthesis: Constituents And Circumstance At The Transcriptomic And Molecular Levels, Mehran Dastmalchi

Electronic Thesis and Dissertation Repository

Isoflavonoids are specialized metabolites, almost exclusive to the legume family of plants. They are actors in symbiosis with nitrogen-fixing bacteria and in plant stress response. Isoflavonoids are noted for their human health benefits. Isoflavonoid content in legumes has proven to be a complex trait. The goal of the present research is to determine the mechanisms underlying isoflavonoid biosynthesis in soybean.

The first approach was to unravel the genetic factors of isoflavonoid biosynthesis. A branch-point enzyme of the phenylpropanoid pathway, chalcone isomerase (CHI), catalyzes the reaction producing flavanones, the nucleus for many downstream metabolites such as isoflavonoids. I identified twelve soybean …