AUX/IAA转录因子调控马铃薯根系建成抵御干旱胁迫的分子机制

Potato is sensitive to drought resistance because of it's shallow fibrous root system. AUX/IAA transcription factor can regulate roots geotropism growth and plant can absorb more water to improve the drought tolerance. However, little is known on AUX/IAA transcription factor regulation in potato root development. Two potato varieties of significant different drought tolerance and root system architecture have been obtained from previous study. In this study, RNA-Seq, Real-time PCR, Agrobacterium mediated transgenic technology, dual luciferase assay of transiently transformed tobacco leaves, the evaluation of potato drought resistance and root analysis technique will be employed to deeply elucidate regulatory mechanism of AUX/IAA transcription factors on root system architecture in potato drought resistance: (1) Differentially expressed AUX/IAA transcription factors will be screened in potato roots under drought stress; (2) AUX/IAA transcription factors expression pattern will be analysised and the key AUX/IAA transcription factor will be found; (3) AUX/IAA transcription factors will be over expression and inhibited expression in transgenic potato plants, and root characteristics will be analysised, the function of AUX/IAA transcription factors will be verificated; (4) The mechanism of AUX/IAA transcription factor regulating downstream genes will be clarified; (5) Root structure characteristics and relationship with drought tolerance under field drought conditions. And then Regulatory mechanism of AUX/IAA transcription factors on root system architecture in potato drought resistance will be revealed. This work will provide the genetic resources for breeding and developing a new field for utilization of potato.

马铃薯为须根系作物，根系浅是其不抗旱的主要原因，AUX/IAA转录因子可调控植物根系的向地性生长从而吸取更多水份提高耐旱性，但其调控马铃薯根系发育的研究未见报道。本研究以前期筛选的抗旱能力差异明显且根系结构差异大的2个马铃薯品种为研究对象，利用RNA-Seq、Real-time PCR、农杆菌介导的转基因技术、Dual Luciferase Assay、马铃薯抗旱性评价等技术进行干旱胁迫下AUX/IAA转录因子调控马铃薯根系建成的分子机制研究：（1）筛选根系不同组成间差异AUX/IAA转录因子；（2）分析根系AUX/IAA转录因子表达模式、挖掘关键基因、验证基因功能；（3）阐明AUX/IAA转录因子对下游功能基因的调控机理；（4）解析大田干旱环境下，转基因植株根系结构特点及其抗旱性。从而全面揭示AUX/IAA转录因子在马铃薯抵御干旱环境中根系建成的调控机制，为马铃薯抗旱品种创制奠定基础。

马铃薯（Solanum tuberosum L.）根系浅导致其不抗旱。研究AUX/IAA转录因子调控马铃薯根系发育及向地性生长有利于其吸取更多水分提高耐旱性。本研究以抗旱能力差异明显且根系结构差异大的2个马铃薯品种为研究对象，利用RNA-Seq、Real-time PCR及农杆菌介导的转基因技术进行干旱胁迫下AUX/IAA转录因子调控马铃薯根系建成的分子机制研究：（1）筛选干旱胁迫下不同品种根系不同组织间差异AUX/IAA转录因子6个：Aux/IAA3, Aux/IAA6, Aux/IAA18, Aux/IAA22, Aux/IAA24和Aux/IAA25；（2）获得转Aux/IAA3, Aux/IAA6, Aux/IAA22和Aux/IAA24过表达和RNAi 表达马铃薯株系各5个；（3）抗旱性评价显示干旱环境下，Aux/IAA3和 Aux/IAA6可调控马铃薯根系发育抵御干旱胁迫。该项研究为马铃薯抗旱品种创制奠定基础。