小麦膜结合转录因子NTL1负调控盐胁迫响应的分子机理研究

In recent years, the membrane-bound transcription factors named NTLs (NTM1 - Like) in the NAC family have received extensive attention and accumulated research results are mainly from the model plant Arabidopsis thaliana. So far, the physiological function and mechanical research of NTL in monocotyledon has not yet been reported. Previously, we cloned a new member of NTL protein family, TaNTL1, from salt-tolerant new variety of wheat introgressive line Shanrong No. 3 (SR3). TaNTL1 over-expressing transgenic Arabidopsis and wheat lines showed salt sensitive phenotype and its RNAi down-regulating transgenic wheat showed salt tolerance phenotype. TaNTL1 interacting protein NIP1 (NTL Interacting Protein 1) was obtained through yeast two hybrid screening. Bimolecular fluorescence complementation (BiFC) experiment also proved that TaNTL1 interacts with NIP1 in planta. In this project, we intend to seek downstream target genes of TaNTL1, to make clear the genetic and physiological function of NIP1, to study the interacting ways of TaNTL1 and its partner NIP1, so as to reveal the molecular mechanism of TaNTL1 negatively regulating salt stress response. The completion of this project will provide a new strategy, new genes and new materials for the high yield and salt-resistance transgenic breeding of common wheat.

迄今为止，国内外对于膜结合转录因子NTLs（NTM1-Like）在单子叶植物中的生理功能和作用方式的研究尚未见报道。我们从小麦渐渗系耐盐新品种山融3号（SR3）中克隆到了NTL蛋白家族新成员TaNTL1。TaNTL1过量表达的拟南芥和小麦转基因株系都表现出盐敏感的表型，而其RNAi下调表达的转基因小麦则表现出盐耐受的表型。利用酵母双杂交系统筛选到TaNTL1的相互作用蛋白 NIP1（NTL Interacting Protein 1）。双分子荧光互补（BiFC）实验也证明TaNTL1与NIP1在植物体内存在相互作用。本项目拟寻找TaNTL1转录因子所调控的下游靶基因；明确NIP1的遗传及生理功能；研究TaNTL1与NIP1蛋白的调控关系，从而揭示TaNTL1负调控盐胁迫信号的作用机制，为普通小麦的高产、抗盐转基因育种提供新策略、新基因及耐逆新材料。

土壤盐渍化严重影响着农作物产量，如何应对土壤盐渍化是现代农业的一个重要课题。迄今为止，国内外对于膜结合转录因子 NTLs（NTM1-Like）在单子叶植物中的生理功能和作用方式的研究尚未见报道。前期，我们从小麦渐渗系耐盐新品种山融 3 号（SR3）中克隆到了 NTL 蛋白家族新成员 TaNTL1。TaNTL1 过量表达的拟南芥和小麦转基因株系都表现出盐敏感的表型，而其 RNAi 下调表达的转基因小麦则表现出盐耐受的表型。本研究利用酵母双杂交系统、蛋白共定位及GST-Pull down等手段证明了TaNTL1与NIP1（NTL Interacting Protein 1）具有相互作用。通过RNAseq技术寻找到了TaNTL1转录因子所调控的下游靶基因；明确了NIP1的遗传及生理功能；弄清了TaNTL1与NIP1蛋白的调控关系，从而初步揭示了TaNTL1 负调控盐胁迫信号的作用机制，为普通小麦的高产、抗盐转基因育种提供新策略、新基因及耐逆新材料。