| 研究実績の概要 |
Gibberellic acid (GA) and sugars can have synergistic effects on plant growth and yield. Surprisingly, members of the SWEET transporter family, which are responsible for sucrose transporter, have also been found to transport GA. This dual specificity of SWEETs for sugars and GA provides a potential nexus to understand the interactions between these two compounds. We here develop approaches to dissect the contribution of sugars and GA and lay the basis for engineering improved plants. To understand how sucrose and GA bind to SWEET, we performed computational simulations, specifically molecular dynamics simulation and docking simulation between SWEET13 and sucrose as well as GA based on their structures. Through these simulations, we identified amino acids in SWEET13 that recognize sucrose and GA. Subsequently, using cell cultures, we confirmed that these amino acids were necessary to recognize sucrose and GA when they bind to SWEET13. These findings have allowed us to manipulate the selectivity of SWEET for two substrates, sucrose and GA.
|
| 現在までの達成度 (区分) |
現在までの達成度 (区分)
1: 当初の計画以上に進展している
理由
Several SWEET transporters have been demonstrated to mediate transport of the plant hormone gibberellin (GA). The close physiological relationship between sucrose and GA raised the questions of whether a functional interaction exits between these two substrates and whether they are both physiologically relevant. To address these inquiries, molecular docking and molecular dynamics simulations were conducted to predict the amino acids responsible for each substrate binding. Transport activity assays were then performed, which revealed mutants that selectively transport either sucrose or GA. These mutants were used to determine the physiological contribution of two different substrates facilitated by the same transporter.
|
| 今後の研究の推進方策 |
We will continue to explore the physiological relevance of sugar and GA transport activity of SWEETs. Additionally, we will endeavor to identify novel factors implicated in the governance of SWEET transport activity, with the object of comprehending the molecular mechanism of selectivity regulation. Furthermore, we aim to develop a highly sensitive GA biosensor to facilitate an understanding of SWEET-mediated GA dynamics in planta.
|
