Comparative analysis of ABA-mediated stress regulatory networks across the Brassicaceae
Abstract/Contents
- Abstract
- Plants are exposed to a wide range of abiotic stresses in the environment including drought, freezing, and soil salinity. Over evolutionary time, plants have acquired adaptive strategies to survive these stressors. A common type of stress-tolerant plant is a halophyte, which lives along ocean shorelines or near hypersaline lakes. Currently, the gene regulatory networks that underlie a halophyte's adaptation to stress are unknown. Studies in stress-sensitive plants like domesticated crops and Arabidopsis have identified the plant hormone ABA (abscisic acid) as a major regulator of several plant stress responses. Upon the onset of stress, transcription factors downstream of ABA signaling, known as ABRE binding factors (ABFs), activate stress-response genes by binding to cis-regulatory elements known as ABA response elements (ABREs). While components of the ABA-mediated gene-regulatory network have been established in stress-sensitive plants, the regulatory map in the halophytes may have a distinct architecture that underlies adaptive traits. Using root growth assays, I found that halophytes are less sensitive to the growth inhibitory effects of ABA than glycophytes. To identify molecular level differences that mediate growth regulation under stress, I used RNA-Seq and DNA affinity purification (DAP-Seq) and found that halophytes differ in the spatial and temporal expression of genes upon ABA treatment. Some of the halophyte specific genes are associated with previously identified stress tolerance pathways in glycophytes, such as those for cell wall modification and for toxin breakdown. The expression pattern differences are partially mediated by changes in the ABF binding landscape, determined using DAP-Seq. These findings suggest a transcriptional rewiring of ABA-mediated gene-regulatory networks in the halophytes that may contribute to their enhanced tolerance to environmental stress.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2019; ©2019 |
| Publication date | 2019; 2019 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Sun, Ying |
|---|---|
| Degree supervisor | Dinneny, Jose |
| Thesis advisor | Dinneny, Jose |
| Thesis advisor | Long, Sharon |
| Thesis advisor | Morrison, Ashby J |
| Thesis advisor | Wang, Zhiyong |
| Degree committee member | Long, Sharon |
| Degree committee member | Morrison, Ashby J |
| Degree committee member | Wang, Zhiyong |
| Associated with | Stanford University, Department of Biology. |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Ying Sun. |
|---|---|
| Note | Submitted to the Department of Biology. |
| Thesis | Thesis Ph.D. Stanford University 2019. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2019 by Ying Sun
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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