核孔蛋白是细胞核与细胞质之间信息交流的重要载体，但目前仅有少数植物核孔蛋白的部分功能被诠释。申请人在前期研究工作中，用遗传学方法筛选鉴定到核孔蛋白SBB1/NUP85直接调控拟南芥受体激酶BAK1介导的自发性细胞死亡，其功能缺失突变能阻止部分关键蛋白入核并调控内源水杨酸含量。蛋白组学及遗传学研究发现DEAD box类RNA解旋酶DRH1与SBB1在同一复合物共同调控细胞死亡和mRNA出核。然而，它们共同调控细胞死亡的分子机理还不清楚。本项目将在此基础上，运用分子遗传学、生物化学、细胞形态学及组学等方法探索核孔蛋白调控mRNA和蛋白的核质转运机制，进一步深入揭示SBB1和DRH1调控的核质穿梭蛋白和mRNA在BAK1介导的细胞死亡信号转导中的作用，其结果将有助于我们进一步认识植物核孔蛋白新的生物学功能以及植物细胞死亡信号转导途径，并为利用生物技术手段改良农作物使其抗逆高产提供理论依据。

Nucleoporin is an important carrier for nucleocytoplasmic trafficking, but only partial functions of a few plant nucleoporins have been annotated up to now. In our previous studies, a nucleoporin named SBB1/NUP85, was identified to directly modulate Arabidopsis receptor-like kinases BAK1-mediated spontaneous cell death control via a genetic suppressor screen. Loss-of-function of SBB1 is able to specifically prevent several key proteins importing into the nuclei and moderate endogenous salicylic acid content. Proteomics and genetics evidence have shown that a DEAD box RNA helicase DRH1 locates in a protein complex with SBB1 in regulating spontaneous cell death and mRNA export from the nuclei. However, the molecular mechanisms of cell-death control by SBB1 and DRH1 are still largely unknown. Based on our results in previous studies, our current proposal is aimed to explore the nucleocytoplasmic transportation mechanisms of mRNA and proteins by nucleoporins and to further elucidate the molecular mechanisms of SBB1 and DRH1 controlled nucleocytoplasmic trafficking of proteins and mRNAs in BAK1-mediated spontaneous cell-death control by using genetic, biochemical, molecular biology, cell morphology and omics approaches, which will help us to further understand the novel functions of the plant nucleoporins and signal transduction of plant cell death and provides more theoretical proofs for crops improvement by biotechnologies.