Project background
Scientific Background
Plants need to respond to the environment to adapt and grow. Plants modify the concentration of calcium ions in their cells in response to different environmental stimuli and stresses. These changes in cellular calcium concentration trigger many downstream responses, including re-programming of gene expression. Calcium signalling pathways are therefore essential for plants to respond and adapt to environmental stresses.
Flowering plants, such as the model plant Arabidopsis thaliana, have complicated networks of proteins associated with calcium signalling pathways. Genetic redundancy is observed and has hindered further study of these signalling pathways. Our recent genomic analyses have revealed that gene families encoding components of calcium signalling pathways are considerably smaller in other model plant species, including in the liverwort Marchantia polymorpha. The study of these pathways in M. polymorpha therefore offer a unique opportunity to understanding calcium signalling pathways in plants and provide an evolutionary assessment of how plants respond and adapt to environmental stresses in the context of global climate change.
Research Methodology
Objectives:
- Assess physiological responses of M. polymorpha to environmental stresses
The student will grow M. polymorpha plants under lab conditions and assess growth physiology when the plants are exposed to various environmental stresses. The student will particularly focus on salt stress and drought to align with our other NERC-funded work. If time permits, the student will also grow existing mutant plants with calcium signalling genes knocked out to test whether these genes are involved in salt stress and/or drought in M. polymorpha. This objective will determine the physiological responses of M. polymorpha growing under different environmental conditions.
- Measure abiotic stress-induced calcium signals
The student will use existing M. polymorpha lines expressing the calcium reporters aequorin and R-GECO to measure calcium signals in response to different environmental stresses (focussing on salt stress and drought, to align with Objective 1). They will assess whether different calcium signals are triggered in different tissue types, as in vascular plants. This objective will survey the breadth of calcium signals induced by environmental stresses and identify where in M. polymorpha these signals occur.
- Measure expression of calcium signalling genes using qRT-PCR
The student will extract RNA from plant samples harvested in Objective 1, create cDNA and measure expression of selected calcium signalling genes using qRT-PCR. This work will link expression of calcium signalling genes to environmental factors that govern plant growth. Although technically more challenging for an undergraduate, this molecular work will provide the student with excellent molecular experience to complement the plant physiology and cell biology work in earlier objectives.
Overall, this project will allow the student to gain first-hand experience of how scientific research operates, providing them with excellent training opportunities in diverse techniques within the NERC remit. The student will learn how to design and plan their own experiments. They will also learn the importance of appropriate experimental controls and how to interpret data to inform future work. The student will join a supportive lab environment and will importantly learn to develop their skills to work independently.
