Genetics and Genomics Commons^™

Spatiotemporal Transcriptome Diversity And Responses To Salinity Tolerance In The Extremophyte Schrenkiella Parvula, Chathura Wijesinghege

LSU Doctoral Dissertations

Schrenkiella parvula is an extremophyte model related to the most widely studied plant model, Arabidopsis thaliana and Brassica crops in the mustard family (Brassicaceae). It can thrive in highly saline environments where the soil is enriched in Na⁺, K⁺, Li⁺, borates, and chlorides. Understanding how this extremophyte can survive high salinity with genomic adaptations can provide insight into developing stress resilient crops in the future. Gene expression of S. parvula in response to salt has been investigated using shoot and root tissue from mature vegetative-phase plants. However, prior studies have not examined the transcript …

Investigation Of Arabidopsis Extremophyte Relatives, Schrenkiella Parvula And Eutrema Salsugineum Reveals Different Roads Leading To Salt Stress Tolerance, Kieu-Nga Thi Tran

LSU Doctoral Dissertations

How plants adapt to salt stress has been a central question in plant biology for decades. Yet we have not been able to fully understand the molecular networks and genetic mechanisms underlying this complex trait. Most of the genetic work on salinity stress has focused on understanding salt stress responses in the leading, yet a salt-sensitive model Arabidopsis thaliana. With the recent availability of genomes for wild-relatives of A. thaliana, we can now investigate how naturally salt adapted plants may have evolved modified or novel molecular networks to adapt to salt stress. Therefore, my research utilizes a comparative …

Understanding Potassium Toxicity Stress Responses Of The Extremophyte Schrenkiella Parvula Using Systems Biology Approaches, Pramod Pantha

LSU Doctoral Dissertations

Schrenkiella parvula is an extremophyte model closely related to Arabidopsis thaliana and Brassica crops. Its natural habitat includes shores of saline lakes in the Irano-Turanian region. It has adapted to grow in soils rich in multiple salts including Na⁺ and K⁺. I have investigated the genetic basis for high K⁺ tolerance in plants using S. parvula as a stress tolerant model compared to the premier plant model, Arabidopsis thaliana which is highly sensitive to salt stresses using physiological, ionomic, transcriptomic, and metabolomic approaches. Under high K⁺ stress, root system architecture changes significantly compared to control …

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 …

The Role Of Chromatin State Transitions In Modulating Early Phosphate-Deficiency Response Genes In Plants, Maryam Foroozani

LSU Doctoral Dissertations

Phosphorus (P) is an essential plant macronutrient vital to fundamental metabolic processes. Plant-available P is low in most soils, making it a frequent limiter of growth. Declining P reserves for fertilizer production exasperates this agricultural challenge. Plants modulate complex responses to fluctuating P levels via global transcriptional regulatory networks. Although chromatin structure plays a substantial role in controlling gene expression, the chromatin-level mechanisms involved in regulating P homeostasis have not been determined.

In this work, I used chromatin immunoprecipitation (ChIP) combined with next-generation DNA sequencing (ChIP-seq) to map the distribution of H3K4me3 in rice (Oryza sativa L.) during both …