GREEN-SPECIALISTS · Specialised plant cell types via developmentally-controlled gene knockouts: a key step towards fully customised plants

Specialised plant cell types via developmentally-controlled gene knockouts: a key step towards fully customised plants

Anthropogenic climate change is altering the environment faster than plants can adapt. Sensitivity to increasing temperatures, unpredictable rainfall and increased threats from insects and microbial pathogens are all substantial risks to crop security and there are limits to how well these risks can be managed through improved farming practices. In the last century most crop plants have been improved by randomly mutating their seeds with radiation or chemicals, and then selecting new mutant plants with desirable properties like increased yields. The idea of modifying plants to climate-proof our food supply is being examined by scientists and government agencies worldwide. At this stage it is not clear whether the random mutagenesis approaches used in the past will be sufficient. It appears increasingly likely that we will need the ability to edit a plant’s genetic plan in a very precise and planned way. The last decade has heralded the rise of CRISPR-Cas9-based methods of genome modification. This new technology allows scientists to precisely remove or edit specific parts of a plant’s DNA. Usually when the genome of an organism is edited, that modification exists permanently in every cell and is passed on to every cell in subsequent generations. But plants are highly sophisticated organisms with many different specialised cell types that each contribute particular roles to the overall function of the plant. Plants have some cells that are responsible for producing food or chemicals, and these are supported by cells responsible for other vital functions like photosynthesis, nutrient supply, and providing the plant with physical structure. The overall objective of this study was to improve our technical ability to modify plants, in the hope that this will contribute to improving global food security. To engineer plants in a sophisticated way, we need to be able to edit specific cell types rather than applying modifications uniformly across the whole organism. This project aimed to investigate ways to modify particular cells in the leaves of plants without affecting the rest of the plant. The study focused on guard cells: these cells control the movement of water vapour and gases (like carbon dioxide) in and out of the leaf. Guard cells are very important for regulating a plant’s response to increased CO2 concentrations and changes in rainfall and humidity.

Data: CORDIS, © European Union