Plants generate energy through photosynthesis throughout the day, and need a way to store this energy at night in order to maintain growth when there is no sunlight available.
They do this in the form of starch, a carbohydrate made up of many glucose chains, which are bundled together into an insoluble starch granule. Fixed carbon is stored as transitory starch in the chloroplasts of leaves.
Jiawen’s project aims to look at the biochemical mechanisms behind the first steps of starch granule initiation, and the proteins that determine the timing of granule initiation, thereby influencing the number, size and shape of granules in a chloroplast.
Primarily Jiawen is using the model organism Arabidopsis to look at protein interactions that influence leaf transitory starch formation.
Starch is also formed in amyloplasts of storage organs such as seeds and tubers. This storage starch is what we use for human consumption. The extensive research in Arabidopsis is now allowing the group to probe for protein functions in agriculturally important crops such as wheat.
A second part of Jiawen’s project involves looking at the same starch granule initiation proteins in wheat leaves and grains, and determining whether they have similar or different functions compared to Arabidopsis.