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Cytosolic Acetyl-Coa Promotes Histone H3 Lysine 27 Acetylation In Arabidopsis, Chen Chen

Electronic Thesis and Dissertation Repository

Acetyl-coenzyme A (acetyl-CoA) serves as a central metabolite in energy metabolism and biosynthesis. High level of acetyl-CoA can fuel the tricarboxylic acid (TCA) cycle to generate energy and store excess energy in fatty acids. Meanwhile, it also provides acetyl groups for protein acetylation, which normally occurs at the lysine or arginine residues. Acetylation regulates protein functions largely due to the change of total charges. Acetylation of histones, for example, can lead to loss of the interaction between histone and DNA, thus relaxing chromatin structure and potentially promoting gene expression. However, whether and how acetyl-CoA regulates plant chromatin remains unexplored. Here, …

An Investigation Of The Plant Growth Promoting Abilities Of Pseudomonas Fluorescens Uw4 Under Toxic Metal Stress, Joshua J. Frank

Electronic Thesis and Dissertation Repository

I investigated plant-microbe-metal interactions under metal stress. In theory, plant growth promoting rhizobacteria (PGPR) promote plant growth by reducing stress ethylene and synthesizing indole-3-acetic acid (IAA). The putative PGPR Pseudomonas fluorescens UW4 and a mutant strain that lacked an enzyme critical to the reduction of plant ethylene were studied to determine if they could promote Arabidopsis thaliana growth under cadmium and copper stress conditions. Both strains of P. fluorescens UW4 adhered to roots and synthesized IAA, and the wild-type lowered metal stress-induced ethylene in Arabidopsis, but neither strain enhanced plant growth. Wildtype P. fluorescens UW4 and its mutant had …

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 …

Characterization Of A Putative Activation Domain In The Hulk Gene Family, Christopher Doan

Electronic Thesis and Dissertation Repository

The HULK gene family participates in regulation of both flowering time and development in the plant Arabidopsis thaliana. The proteins encoded by these genes share conserved domain structures including a proline-rich region (PRR) in the carboxyl-terminus. Based on sequence analysis and the presence of a proline-rich domain, it has been suggested that the HULKs are putative transcription factors in which HUA2 is known to regulate several late-flowering genes: FLC, FLM and MAF2.

To investigate the putative transcriptional activation domain in the carboxyl-terminus of the HULKs, full-length HULKs and deletion constructs were 3-AT titrated in yeast-one hybrids. It …