Research Fellows Directory
Dr Keara Franklin
University of Bristol
Temperature and light are two of the most important environmental stimuli regulating plant development. Light signals are perceived using a family of photoreceptors named phytochromes. My current research is investigating crosstalk between ambient temperature and phytochrome signalling in plants. When growing in crowded communities, plants compete with neighboring vegetation for light to fuel photosynthesis. The presence of neighboring vegetation is detected as a reduction in the ratio of red to far red wavelengths (low R:FR ratio) in the light reflected from or transmitted through green tissues. This change in light quality is perceived by phytochrome and initiates a suite of elongation responses termed the shade avoidance syndrome, often at the expense of leaf development and plant biomass. These responses serve to elevate leaves towards gaps in the canopy and enable plants to overtop competitors. We have observed that plants display a very different shade avoidance strategy when grown at cooler temperatures and are now dissecting regulatory mechanisms involved.
When plants are grown at high temperature, they display a suite of developmental responses similar to the standard shade avoidance syndrome, suggesting light and temperature sensing pathways may share signalling mechanisms. We have established that the phytochrome-interacting protein PHYTOCHROME INTERACTING FACTOR 4 is a master regulator of high temperature-mediated elongation growth in Arabidopsis and are now dissecting the molecular signalling pathway(s) involved. We are also investigating the effects of stem elongation on leaf cooling at high temperatures.
This research programme addresses fundamental mechanisms of plant growth and is therefore of interest to all plant biologists. Understanding the molecular mechanisms through which plants respond to changes in ambient temperature is of increasing importance with regard to understanding the effects of global climate change on crop productivity
Interests and expertise (Subject groups)