Understanding photosynthetic thermotolerance: from temperature sensing to heat resilience

About the project

About the Project Photosynthesis underpins almost all ecosystems on Earth. It represents the largest flux of CO₂ between the atmosphere and biosphere, providing a major carbon sink that helps mitigate anthropogenic CO₂ emissions while also being central to crop productivity and food security. Photosynthesis is strongly affected by temperature, with negative impacts occurring at lower temperatures than in other key processes such as respiration. As a result, photosynthesis is a major determinant of whole-plant temperature tolerance. Climate change is driving global temperatures to record levels, with increases in the frequency, intensity, and duration of extreme heat events. These changes are pushing plants towards the limits of their thermal tolerance, with recent heatwaves causing large-scale forest dieback and significant crop yield losses. Understanding the mechanisms underlying photosynthetic thermotolerance is therefore a major challenge in plant biology. Addressing it will improve our ability to predict plant responses to future climates and lay foundations for engineering crops that are more resilient to climate change. Photosynthesis involves processes acting across multiple spatial and temporal scales and, as such, photosynthetic thermotolerance is controlled by multiple mechanisms. Several of these mechanisms have been identified, including changes in thylakoid membrane fluidity, increased synthesis of protective enzymes, and altered expression of key photosynthetic genes. These processes are all activated in response to high temperature; however, the temperature perception pathways upstream of these responses remain largely uncharacterised. This project aims to identify and characterise the temperature perception pathways that regulate photosynthetic thermotolerance through three interconnected research areas: 1. Sensing temperature: What are the temperature sensors upstream of photosynthetic thermotolerance? Temperature perception in plants is likely to be distributed, with distinct perception pathways controlling different physiological outputs rather than one or a few master temperature sensors. In this part of the project, you will screen known temperature-perception mutants in Arabidopsis thaliana and assess their effects on photosynthetic thermotolerance while also seeking to identify novel components of temperature-signalling pathways. For mutants displaying clear phenotypes, you will investigate the underlying mechanisms to determine how the mutation affects photosynthetic thermotolerance. This will help establish whether multiple temperature-perception pathways exist or whether a central regulatory mechanism operates upstream of photosynthetic thermotolerance. 2. Defining the pathway: How are temperature cues integrated into photosynthetic responses? The goal of part two is for you to define the pathway that leads to photosynthetic thermotolerance from temperature perception to physiological output. You will combine RNA- and ATAC-sequencing data with measurements of photosynthetic physiology to identify changes in gene expression and transcription factor networks that underlie photosynthetic thermotolerance. 3. Real world environments: How do temperature perception pathways interact with other environmental signalling pathways? In the field, high temperatures tend to co-occur with other environmental conditions such as high light, high UV and low water availability and there is substantial cross talk between environmental signalling pathways. Here, in collaboration with Prof Kerry Franklin (University of Bristol) you will investigate the interaction of high temperature signalling pathways with other environmental variables to better understand how photosynthetic thermotolerance functions in real world environments. Supervision Environment You will be based in the Dickinson lab at the University of Bristol where we work on understanding the genetic basis of photosynthetic adaptation to the environment. You will join a supportive and collaborative environment with lab space, meetings and equipment shared between multiple plant science research groups, including that of Prof Kerry Franklin, who you will collaborate with on this project. Application Process I welcome informal enquiries from prospective applicants who would like to discuss the project further. To apply, please email Patrick Dickinson ( patrick.dickinson@bristol.ac.uk ) by the end of the day on Friday 13th November , attaching: A CV A one-page cover letter outlining why you are interested in the project and why you believe you would be a good fit Following the initial application stage, one candidate will be invited to work with the supervisor to develop a full research proposal before the final interview in January.

Research areas