Control of gibberellin signaling, gibberellin sensing and interplay of gibberellin with sucrose

赤霉素和糖对植物生长和产量具有协同效应。令人惊讶的是，负责蔗糖转运的SWEET转运蛋白家族成员也被发现转运GA。SWEETs对糖和GA的双重特异性为理解这两种化合物之间的相互作用提供了潜在的联系。我们在此开发方法来剖析糖和GA的贡献，并为工程改良植物奠定基础。为了了解蔗糖和GA如何与SWEET结合，我们进行了计算模拟，特别是基于SWEET13与蔗糖和GA结构的分子动力学模拟和对接模拟。通过这些模拟，我们确定了SWEET13中识别蔗糖和GA的氨基酸。随后，通过细胞培养，我们证实当蔗糖和GA与SWEET13结合时，这些氨基酸是识别蔗糖和GA所必需的。这些发现使我们能够操纵SWEET对蔗糖和GA两种底物的选择性。

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.