Studies into the link between plant development and abiotic stress tolerance in Arabidopsis thaliana

Abstract

The links between plant development and responses to stress, both biotic and abiotic, is an area of major interest. With an ever increasing food production requirements, and changes in climate putting strain on a plants intrinsic ability to cope with altering conditions, the potential for modulating stress responses is a research area of great potential.
A major regulator of plant growth and development is a class of proteins called the DELLA proteins, which act as negative regulators of gibberellic acid signalling. Potential interactors of the DELLA proteins were identified as WRKYs transcription factors; a major family of plant transcription factors involved in the regulation of a wide variety of processes. Research conducted showed that WRKY transcription factors and DELLA proteins interact in planta. A specific target of interest, AtWRKY26, was shown to interact strongly with the Arabidopsis DELLA protein, AtRGA. Specific protein domains where interaction occurs were also identified via domain mutational techniques, whereby individual domains were baited against full length proteins. The function of AtWRKY26 was further elucidated after identifying knock out mutants, highlighting decreased tolerances to heat shock in wrky26 plants. Relative gene expression of AtWRKY26 was also demonstrated to vary between wild type and DELLA mutants, further highlighting the interaction between these proteins. This highlights the potential for modulating protein levels to alter stress responses.