Seed oil, seed coat mucilage and cuticular wax deposition are interconnected in Arabidopsis thaliana
department or school: Science, Faculty of
department or school: Botany, Department of
data provider: DSpace
degree campus: UBCV
creator: Shi, Lin
issued: 2015-07-31T00:00:00Z
issued: 2014
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Seed oil, seed coat mucilage and cuticular wax are plant-specific metabolites important for plant development and growth. Therefore, understanding biosynthesis, deposition, transport and regulation of these metabolites will benefit our daily life and the environment. The original objectives of my thesis research were to investigate the regulation of seed oil accumulation by a transcription factor GLABRA2 (GL2; chapter 2) and to explore the secretory process involved in the transport of cuticular waxes from the endoplasmic reticulum to the plasma membrane (chapter 3) in Arabidopsis thaliana. However, my research revealed two unexpected connections between seed oil and seed coat mucilage deposition and between cuticular wax export and cell wall formation. At the beginning of chapter 2, I hypothesized that GL2 may regulate seed oil biosynthesis by controlling PHOSPHOLIPASE D ZETA (PLDZ) genes in the embryo. However, my data demonstrated that GL2, and all of the transcription factors known to be required for GL2 expression, influence seed oil accumulation in the embryo by regulating transcription of a seed coat mucilage biosynthetic gene, MUCILAGE MODIFIED 4 (MUM4) in the seed coat. Based on this evidence, I propose that mucilage biosynthesis in the seed coat competes with oil biosynthesis in the embryo for available photosynthate during seed development. This information suggests a promising way to engineer high oil yields in seeds by blocking seed coat mucilage production. In chapter 3, I characterized deposition of stem cuticular wax, seed coat mucilage and secondary cell wall columella, and secretion in the cer11-1 mutant. The pleiotropic cer11-1 phenotype suggests that CER11 plays a role in secretory trafficking involved in the deposition of apoplastic matrix components, including cuticular wax, seed coat mucilage and cell wall constituents. Cloning of the CER11 gene revealed that it encodes C-TERMINAL DOMAIN PHOSPHATASE LIKE 2 (CPL2) that interacts with a vacuolar…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/47140
note: SEED OIL, SEED COAT MUCILAGE AND CUTICULAR WAX DEPOSITION ARE INTERCONNECTED IN ARABIDOPSIS THALIANA by Lin Shi B.Sc., Nankai University, 2002 M.Phil., City University of Hong Kong, 2007 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in The Faculty of Graduate and Postdoctoral Studies (Botany) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) July, 2014 © Lin Shi, 2014 ii ABSTRACT Seed oil, seed coat mucilage and cuticular wax are plant-specific metabolites important for plant development and growth. Therefore, understanding biosynthesis, deposition, transport and regulation of these metabolites will benefit our daily life and the environment. The original objectives of my thesis research were to investigate the regulation of seed oil accumulation by a transcription factor GLABRA2 (GL2; chapter 2) and to explore the secretory process involved in the transport of cuticular waxes from the endoplasmic reticulum to the plasma membrane (chapter 3) in Arabidopsis thaliana. However, my research revealed two unexpected connections between seed oil and seed coat mucilage deposition and between cuticular wax export and cell wall formation. At the beginning of chapter 2, I hypothesized that GL2 may regulate seed oil biosynthesis by controlling PHOSPHOLIPASE D ZETA (PLDZ) genes in the embryo. However, my data demonstrated that GL2, and all of the transcription factors known to be required for GL2 expression, influence seed oil accumulation in the embryo by regulating transcription of a seed coat mucilage biosynthetic gene, MUCILAGE MODIFIED 4 (MUM4) in the seed coat. Based on this evidence, I propose that mucilage biosynthesis in the seed coat competes with oil biosynthesis in the embryo for available photosynthate during seed development. This information suggests a promising way to engineer high oil yields in seeds by blocking seed coat mucilage production. In chapter 3, I characterized deposition of stem cuticular wax, seed c…
has type: Thesis/Dissertation
date issued: 2014-09
is shown at: 10.14288/1.0167527
language: eng
degree discipline: Botany
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivs 2.5 Canada
rights URI: http://creativecommons.org/licenses/by-nc-nd/2.5/ca/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/47140