Exploring the cellular basis of environmental stress and plant development: Bioremediation potential of Senna and gene function in Populus
Loading...
Authors
Lai, Zoe
Date
Type
thesis
Language
eng
Keyword
phytoremediation , gene discovery , Senna occidentalis , Populus alba x Populus tremula , phytostabilization , plant transformation , ligand-gated ion channel
Alternative Title
Abstract
This thesis addresses two projects that have been investigated with two different scientific approaches, and yet are linked by the role of ion transporters. Ion transporters play important roles in many different plant processes, including signaling, stress response, and metabolism, and can have large impacts on plant development and health. In the first project, the physiology of Senna occidentalis L. is examined to assess its phytoremediation capabilities. S. occidentalis has previously been identified as a potential plant for the phytoremediation of heavy metal contaminated soils. Here, Senna was exposed to a range of Cd and As treatments, and its tolerance was examined through health parameters of biomass and chlorophyll, proline, and hydrogen peroxide levels. High translocation of the metals from the soil to the roots, but low translocation from root to aboveground tissues, suggest Senna occidentalis to be a good phytostabilizer of Cd- and As-contaminated soils. This result indications that ion transporters play a significant role in moving Cd and As from the soil to the root, but have less of a role in moving them from the root to aboveground tissues. In the second project, a molecular approach was used to investigate the activation-tagged poplar mutant named shriveled leaf. The candidate gene Potri.001G356200.1 was identified due to its 2X upregulated transcript levels in the mutant. The function of the gene is not known but it has been putatively identified as an extracellular ligand-gated ion channel in Arabidopsis. The poplar candidate gene was then cloned, inserted into an overexpression vector, and transformed into wild-type poplar in an attempt to recapitulate the mutant phenotype. Due to the long timeframe required to create transgenic poplars, the transformants are still in tissue culture, but future phenotypic analyses will determine if this gene is responsible for the mutant phenotype. Assuming the transgenic lines mimic the mutant phenotype, this would be the first link of this ion transporter to a distinct developmental phenotype. Together, these studies contribute to our understanding of ion channels in both stress responses and developmental processes.
Description
Citation
Publisher
License
Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada
ProQuest PhD and Master's Theses International Dissemination Agreement
Intellectual Property Guidelines at Queen's University
Copying and Preserving Your Thesis
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.
Attribution-NonCommercial 3.0 United States
ProQuest PhD and Master's Theses International Dissemination Agreement
Intellectual Property Guidelines at Queen's University
Copying and Preserving Your Thesis
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.
Attribution-NonCommercial 3.0 United States