Download the full-sized PDF of Functional characterization of a novel cell-wall annotated PELPK1 gene in Arabidopsis thalianaDownload the full-sized PDF



Permanent link (DOI):


Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Graduate Studies and Research, Faculty of


This file is in the following collections:

Theses and Dissertations

Functional characterization of a novel cell-wall annotated PELPK1 gene in Arabidopsis thaliana Open Access


Other title
cell wall
Type of item
Degree grantor
University of Alberta
Author or creator
Rashid, Abdur
Supervisor and department
Dr. Deyholos, Michael (Biological Sciences)
Examining committee member and department
Dr. Owttrim, George (Biological Sciences)
Dr. Kav, Nat (AFNS)
Dr. Gegan, Sharon (external)
Dr. Hall, Jocelyn (Biological Sciences)
Department of Biological Sciences

Date accepted
Graduation date
Doctor of Philosophy
Degree level
Abstract In silico analysis showed that Arabidopsis thaliana gene AT5G09530 encodes a uniquely repetitive, proline-enriched protein that is conserved across species, and is likely secreted to the cell wall. Based on its most common amino acid repeat motif, I named the gene PELPK1 and its putative paralog PELPK2 (AT5G09520). Reporter (GUS) expression showed that the PELPK1 upstream genomic region is sufficient for expression in the aleurone layer during seed germination, and is induced throughout the plant by biotic factors (especially Pseudomonas syringae infection), defense chemicals (MeJa, salicylic acid), and mechanical wounding, consistent with the presence of conserved regulatory elements. Sub-cellular localization of a translational fusion of PELPK1 with GFP showed that the protein was secreted into seed-coat aleurone cells and to the cell walls of other tissues. Based on these results, it was concluded that the PELPK1 is a cell wall-associated protein and is most actively transcribed during radicle penetration of the seed coat and during pathogen and wounding responses. A proteomic survey of aleurone proteins failed to identify PELPK1, although several proteins not previously associated with this tissue were identified. Mutational analysis demonstrated that RNAi silencing significantly down-regulated the transcript abundance of PELPK1. Phenotypic analysis showed that RNAi plants exhibited significantly slower germination and root growth when the medium was supplemented with sucrose (100mM). Conversely, constitutive overexpression (OX) of PELPK1 enhanced seed germination and root elongation as compared to wild-type (WT). Analysis of soil-grown plants showed slower emergence and slower vegetative growth for RNAi lines, while OX plants exhibited faster emergence and enhanced vegetative growth and flowering as compared to WT. However, PELPK1 RNAi and OX lines did not differ from WT in response to treatment with pathogens. These results show that the abundance of PELPK1 is positively correlated with plant growth rate under some conditions. PELPK1 may influence growth through CW modification or other independent pathways.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (Portable Document Format)
Mime type: application/pdf
File size: 4275897
Last modified: 2015:10:12 13:52:49-06:00
Filename: Abdur Rashid Ph.D. thesis.pdf
Original checksum: 68e5dd6eead1ba5b93549a5ceaa56e12
Well formed: true
Valid: true
File title: 1
File author: deyholos_lab
Page count: 226
Activity of users you follow
User Activity Date