菊芋块茎萌芽成苗过程适应盐胁迫的生理机制解析

Jerusalem aritichoke (Helianthus tuberosus) shows remarkable salt tolerance as well as commercial values. Reproduction of Jerusalem artichoke produced vegetatively by tuber cuttings rather than by the true botanical seed. The physiological mechanism underlying adaptive response to salt stress in sprouting Jerusalem artichoke tubers is completely unknown. The typical physiological characteristics and genome-scale metabolic network of salt adaptation are investigated in sprouting Jerusalem artichoke tubers using a combined approach of comparative physiology and functional genomics technologies such as transcriptomics, proteomics, and metabolomics. The uniformity, homogeneity and repeatability of tuber cell suspension cultures offer ideal characteristics for further confirming the cellular salt adaptive mechanisms. Germination and early seedling growth are critical stages for the establishment of plant populations under saline conditions. But research on the stage of plant germination is still limited thus far. To investigate the adaptive response to salt stress in sprouting Jerusalem artichoke tubers would help us to understand salinity tolerance in plant germination and early seedling growth stage, and would also aid in better understanding the relationship between plant and environment.

菊芋是重要的经济作物并具有很强的耐盐能力，由地下块茎产生新植株是其主要繁殖方式，前期研究结果提示菊芋块茎萌芽成苗过程具有适应盐胁迫环境的特殊生理机制，但并不清楚具体过程。本项研究以前期工作所选育耐盐碱菊芋品系的块茎及其悬浮培养细胞系为材料，采用比较生理学与转录组、蛋白质组、代谢组分析等系统生物学研究手段相结合的方法，通过对耐盐相关典型生理特性及整体生理代谢网络的系统分析，并结合细胞水平的验证和深入解析，在生理水平上揭示菊芋块茎萌芽成苗过程对盐胁迫的适应机理。植物由种子或块茎等繁殖体萌芽而成幼苗的过程，既是植物生活史中最重要和关键的阶段，也是对生存环境最敏感和脆弱的阶段。重视植物胁迫生理生态学研究中疏于关注的萌芽成苗阶段，有利于丰富植物萌发成苗阶段响应与适应盐胁迫机理方面的认知，为全面、深入理解植物与环境的相互关系积累资料。

菊芋是重要的经济作物并具有很强的耐盐能力，由地下块茎产生新植株是其主要繁殖方式，萌芽形成幼苗的过程，既是生活史中最重要和关键的阶段，也是对生存环境最敏感和脆弱的阶段。本项目利用耐盐碱菊芋品系的块茎及其悬浮培养细胞系为材料，对盐胁迫下菊芋块茎萌芽成苗过程中与耐盐性相关的典型生理特性（离子转运与均衡能力、渗透调节作用、抗氧化作用、激素信号变化以及菊糖代谢等）进行了分析，考察了这些生理特性与菊芋块茎萌芽成苗过程适应盐胁迫的相关性。同时，利用系统生物学研究的转录组分析、蛋白质组分析和代谢组分析手段，比较了盐胁迫下菊芋块茎萌芽成苗过程的基因表达、蛋白合成和代谢产物与对照的差异。通过对耐盐相关典型生理特性及整体生理代谢网络的系统分析，在生理水平上解析了菊芋块茎萌芽成苗过程对盐胁迫的适应机理，为深入研究菊芋块茎萌芽的耐盐分子基础提供了依据。