Coming back to life: just add water! Chloroplast assembly in resurrection plants
Dr Christopher Carrie, from Waipapa Taumata Rau the University of Auckland, will investigate how chloroplasts, the tiny factories responsible for photosynthesis, are assembled in resurrection plants. This could lead to increased photosynthetic efficiency and improved crop yields
Published on 3 Whiringa-ā-rangi November 2022
Photosynthesis, where energy from the sun is harvested by plants and some bacteria to convert water and carbon dioxide to biomass and oxygen, is essential to support life on earth. Chloroplasts are the tiny factories inside green plant cells that are responsible for photosynthesis. They contain specialised structures called thylakoid membranes, which house the essential protein complexes that harvest the sun’s energy during the light reactions of photosynthesis. Understanding how chloroplasts and their thylakoid membranes are built is a fundamental biological question, and is essential for future advancements such as increasing photosynthetic efficiency for improved crop yields. However, despite recent advances, the events leading to chloroplast assembly are poorly understood.
Dr Christopher Carrie, from the University of Auckland, along with colleagues from South Africa and Germany, has been awarded a Marsden Fund Standard grant to study how chloroplasts and their specialised photosynthetic machinery are assembled. They will study specifically how this works in resurrection plants, which get their name from their remarkable ability to survive extreme dehydration for months or even years, completely dismantling their chloroplasts and their associated thylakoid membranes. When the dried-out plants are watered, they can rapidly reconstruct their chloroplasts to enable normal photosynthesis to resume. Tolerance to desiccation makes these plants a unique model system to study chloroplast assembly.
Dr Carrie and his team will use a variety of molecular and imaging techniques to map chloroplast and thylakoid assembly. They will be the first team to comprehensively describe the molecular events involved in resurrection after extreme dehydration. The team will gain unprecedented insights into how the photosynthetic machinery is built over time, as well as identifying new genes essential for chloroplast biogenesis. In the future, it could be possible to rewire or redesign chloroplasts to help improve stress tolerance and productivity, particularly in the context of climate change-related impacts and increasing demands on global food production.