Orchestration of three transporters and distinct vascular structures in node for intervascular transfer of silicon in rice

Significance Requirement of mineral elements differs with different organs and tissues; therefore, plants have developed systems for preferentially delivering mineral elements to tissues with high requirement. However, the molecular mechanisms for these systems are poorly understood. We took silicon (Si) as an example and revealed an efficient distribution system occurring in the node of rice, which is a hub for distribution. We found that hyperaccumulation of Si in the husk (more than 10%) is achieved by cooperation of three different Si transporters localized at the different cell layers in the node. Furthermore, mathematical modeling showed that an apoplastic barrier and development of enlarged vascular bundles are also required. Our work revealed a set of players for efficient distribution control in node.