番茄SlAGL104-2基因响应种子引发并调控种子活力的分子机制

Seed priming is a practical technology to improve seed vigor. It is important to ensure rapid and uniform sprouting during industrialized seedling production. However, some technical bottlenecks were still not solved for this technology. For example, for different species, the priming method may be different; for different batches of the same species, the priming conditions and parameters were also different. Exploring molecular mechanism of seed priming technology is necessary to solve this problem. In our study, we established a stable and reliable seed priming system to improve seed vigor in tomato. A new candidate transcription factor SlAGL104-2 response to seed priming closely was selected by transcriptome sequencing and Q-PCR analysis. In this project, the molecular function of SlAGL104-2 was studied by overexpression and CRISPR-Csa9 technology. At the same time, transcriptome sequencing of transgenic tomato lines were used to excavate downstream genes of SlAGL104-2. The Y1H, LUC/REN and EMSA were performed to validate the relationship of these genes with SlAGL104-2. The genetic network of seed vigor regulated by SlAGL104-2 will be established; the molecular mechanism of seed priming regulating seed vigor by SlAGL104-2 in tomato will be clarified. This study would reveal the mechanism of seed priming technology in improving seed vigor. It was also groundwork for gene markers development in seed priming. It would also be help to drive the large-scale application of seed priming technology.

种子引发技术是提高种子活力、保证工厂化育苗出芽快速整齐的重要实用技术。但其仍有许多技术瓶颈尚未解决，比如不同种类种子适宜采用的方法可能不同；相同物种种子批不同，引发条件与参数也要有所改变等。进一步挖掘种子引发技术调控种子活力的分子机制，是解决种子引发技术瓶颈的必经途径。申请人前期建立了稳定可靠的提高番茄种子活力的引发体系，通过转录组学测序和Q-PCR验证分析筛选到一个新的密切响应种子引发的转录因子SlAGL104-2。本项目通过过表达和基因编辑技术研究SlAGL104-2基因的分子功能，同时通过对转基因株系进行测序，挖掘其调控的下游基因，并利用Y1H、LUC/REN、EMSA等实验进行验证，构建该基因调控种子活力的遗传网络，揭示该基因响应种子引发调控种子活力的分子机理。本研究不仅为利用种子引发技术提高种子活力提供了新的线索，也为开发种子引发基因标记，推进种子引发技术的大规模应用奠定基础。

种子活力是种子种用价值的重要组成部分，种子引发是提升种子活力的重要手段，但其作用机理尚不清楚。项目组前期建立了基于PEG的番茄种子引发技术，同时利用转录组学筛选到一个番茄引发种子内特异性表达的新基因SlAGL104-2，并进行了基因功能研究。研究结果表明，基于PEG的种子引发技术能够显著提升种子活力，引发条件为30%PEG/25℃/3d。转基因实验表明，SlAGL104-2负调控种子活力，过表达株系种子发芽缓慢，基因编辑株系种子发芽快，活力高。比较转录组学数据表明，SlAGL104-2可能参与调控能量、氨基酸和碳水化合物代谢。本项目为种子引发终止标记的开发提供依据，也为创制高活力种子提供了理论基础，具有重要的理论意义和实践价值。