AtIPS1与细胞程序化死亡相关蛋白ATXR5/6的相互作用

摘要

[目的]对拟南芥肌醇磷酸合酶AtIPS1进行亚细胞水平定位,并验证AtIPS1与细胞程序化死亡(PCD)相关蛋白ATXR5或ATXR6的相互作用.[方法]构建pAtIPS1::AtIPS1-GFP融合基因表达载体,并分别转化烟草BY-2细胞和拟南芥植株,共聚焦显微镜下观察绿色荧光蛋白GFP的分布.采用双分子荧光互补(BiFC)技术分析AtIPS1与ATXR5/6的相互作用,并观察突变体atips1的表型.[结果]AtIPS1定位于细胞质和细胞核.AtIPS1与ATXR5和ATXR6之间存在相互作用,且互作位点与AtIPS1的细胞定位一致.突变体atips1叶片上自然产生细胞死亡的表型,外源增加肌醇或AtIPS1超表达可恢复突变体的野生型表型,叶片不再出现坏死斑.[结论]AtIPS1突变可导致植物细胞死亡;AtIPS1定位于细胞质和细胞核;AtIPS1通过与ATXR5/6互作参与了植物PCD的调控.%[Objective] The objective of the study was to analyse the localization of AtlPSI and the interaction between AtlPSI and ATXR5/6 related to programmed cell death (PCD) in Arabidopsis thaliana. [Method] The constructs of pAtIPS1::AtIPS1-GFP were introduced in BY-2 cells and plants of Arabidopsis. The fluorescence of GFP was observed under a confocal microscope. The interaction between AtlPSI and ATXR5/6 was analyzed via Bi-Molecular Fluoresence Complementation (BiFC) and the phenotype of mutant atipsl was observed. [ Result ] The results showed that AtIPS1 was accumulated in the cytoplasm and the nucleus. AtIPS1 interacted with ATXR5 and ATXR6. The localisation of AtIPS1 was compatible with an interaction with ATXR5/6. The atipsl mutant displayed the phenotype of the spontaneous lesion formation on leaves. The phenotype of atipsl mutant was complemented and no longer formed lesions by a myo-inositol solution treatment or over-expression the AtlPSI gene. [ Conclusion] This study indicates that the disruption of AtIPS1 results in cell death on leaves. AtlPSI accumulated in the cytoplasm and nucleus. AtIPS1 could be involved in the regulation of PCD through the interaction between AtIPS1 and ATXR5/6.