水稻颖果灌浆过程中蔗糖运输的分子机制

Molecular mechanism of sucrose transport in rice caryopsis during grain filling

水稻灌浆是关系到品质和产量的重要生物学过程,其颖果形态变化和蕴含的生理生化过程受到了广泛的关注和详细的研究。然而,这些形态、生理生化过程背后的分子机制特别是对形成颖果最关键的原料蔗糖的运输过程还有很多问题需要回答。最近一些研究显示运输寡糖的SWEET蛋白和蔗糖-质子同向运输蛋白SUT一起在水稻颖果灌浆过程中的蔗糖运输环节发挥了重要作用,特别是它们在母体与子代细胞之间的蔗糖传递方面有不可替代的功能。这些研究为彻底阐明水稻颖果形成中的同化物运输途径和机制提供了关键证据,同时也为将来利用相关基因并调控其表达以提高水稻产量和品质奠定了分子基础。

Grain filling is a biological process essential for rice quality and productivity. The physiological and biochemical processes underlying the morphological variation of caryopsis during grain filling have been intensively investigated. The molecular mechanism of these processes, particular the mechanism of sugar transport for morphogenesis of the caryopsis, however, remains to be elucidated. Recently, several studies demonstrated that the sugar transporter protein SWEET and sucrose-proton symporter （SUT） collectively participated and played important and indispensable roles in sugar transport during rice grain filling, particularly in the transfer of sucrose from the maternal tissue to the filial tissue at the maternal-filial interface. These studies provided key evidence to elucidate the sugar transport mechanism during the caryopsis development. They also laid the molecular foundation for the improvement of rice quality and productivity in the future by adjusting the expression of these protein encoding genes.