Periodic Reporting for period 2 - MUM-GROW (Molecular Uptake Mechanisms controlling Plant Growth)
Okres sprawozdawczy: 2022-12-01 do 2024-05-31
Correct plant growth and development is completely dependent on sugar uptake in growth zones (the meristem), and made possible in all plants by sugar transporters. Growth polarity is created by an asymmetrical gradient of auxin mediated by auxin transporters. Despite extensive research, the molecular mechanisms of these transporters remains unknown. If we knew the molecular determinants of their function, it would allow us to predict, augment and modify plant responses to a changing environment.
MUM-GROW will address this by using a complementary set of methods founded in structural biology to determine the 3-dimensional structures of key players in these transmembrane transport systems. This will be combined with biochemical characterization to address important mechanistic questions and elucidate their molecular mechanism.
Understanding the mechanisms that govern plasticity in growth is essential for determining resilience of whole ecosystems. MUM-GROW will lead to a breakthrough in our understanding of sugar and auxin homeostasis, a fundamental part of basic plant metabolism. It has tremendous potential for the societal challenge to secure sufficient food for our global population in a sustainable balance between environmental impact and resource exploitation. Furthermore, this proposal will uncover general molecular principles of transmembrane uptake and export pertaining to all organisms.
Objective 1 - Sugar transport:
We have established excellent expression of sugar transporters using a novel expression system, developed by us. We have solved the first structure of a sucrose transporter and used this result to initiate a fully molecular understanding of how sucrose is transported in plants. This initial analysis is published in Nature Plants in 2023.
We have also solved several structures of a glucose transporter and these have expanded on our understanding of how glucose and other monosaccharides are recognized in in plants. The first results here have been published in Nature Plants. Work is ongoing to continue our elucidation of the molecular mechanisms behind sugar transport.
Objective 2 - Auxin transport:
We have established excellent expression and purification protocols for auxin transporters that will help us explain affinity and specificity. Based on this, we have solved and published the first structural and biochemical characterization of a PIN auxin exporters in Nature in 2022. Work is ongoing to continue our elucidation of the molecular mechanisms behind auxin transport.