Finch, Jessica A. (2019) The role of cell cycle regulation in immunity-induced root growth inhibition in Arabidopsis thaliana. PhD thesis, University of Warwick.

PDF WRAP_Theses_Finch_2019.pdf - Submitted Version Embargoed item. Restricted access to Repository staff only until 17 January 2022. Contact author directly, specifying your specific needs. - Requires a PDF viewer. Download (16Mb)

Request Changes to record.

Abstract

Reducing crop losses due to diseases is essential if we are to adequately and sustainably feed a growing global population. Therefore, much research is concerned with increasing plant stress resilience including plant innate immunity against pathogens. However, efforts to increase yield in this way are hindered by the existence of immunity-induced growth inhibition, the cellular and molecular basis of which remains unknown. This project, therefore, set out to investigate growth inhibition induced by pattern-triggered immunity in roots of the model plant Arabidopsis thaliana, with a particular focus on the involvement of cell cycle regulation.

A combination of genetic, molecular, biochemical, transcriptomic and microscopy approaches was employed. Firstly, the expression of key cell cycle regulators was found to be disrupted after immunity elicitation by the exogenous application of different immunity elicitors. Overexpression of certain cell cycle regulators was shown to uncouple growth from immunity, and co-immunoprecipitation was employed to investigate physical interactions between these proteins.

Secondly, a single-cell transcriptomics approach, Drop-Seq, was applied to root meristems for the first time, following optimisation of the experimental protocol. Resulting data were used to investigate sources of transcriptomic variation in meristem cells, and to identify novel cell cycle phase-specific markers. These were used to further investigate the effect of immunity on cell cycle regulation.

Finally, the hypothesis that immunity may induce DNA damage, leading to the activation of plant DNA damage responses, culminating in cell cycle arrest, was investigated. Treatment of roots with immunity elicitors was found unexpectedly to suppress DNA damage response genes and to reduce the severity of DNA damage responses to known DNA damaging agents.

These findings are discussed in light of existing knowledge and a model is proposed to explain the link between pattern-triggered immunity, the cell cycle and growth.

Item Type:	Thesis or Dissertation (PhD)
Subjects:	Q Science > QH Natural history > QH301 Biology Q Science > QK Botany
Library of Congress Subject Headings (LCSH):	Arabidopsis thaliana, Cell cycle -- Regulation, Roots (Botany) -- Physiology, Roots (Botany) -- Effect of stress on
Official Date:	September 2019
Dates:	Date Event September 2019 UNSPECIFIED
Institution:	University of Warwick
Theses Department:	School of Life Sciences
Thesis Type:	PhD
Publication Status:	Unpublished
Supervisor(s)/Advisor:	Schäfer, Patrick ; Ott, Sascha
Sponsors:	Biotechnology and Biological Sciences Research Council (Great Britain) ; University of Warwick
Format of File:	pdf
Extent:	xii, 167 leaves : illustrations (some colour)
Language:	eng

Request changes or add full text files to a record

Repository staff actions (login required)

View Item