红花转录因子CtbZIP1调控油脂合成的作用机制研究

Safflower is one of the oil crops which developd rapidly in the world and its applicationprospects is broad. The oil content of safflower in china was lower than some varieties in other country. It was the lack of competitiveness in the international market. It is difficult to increase the production of safflower seed oil in cultivation techniques now and can’t fill the market gap. However, it is one of the important measures to increase the yield of safflower seed oil. Previous studies showed that CtbZIP1 was an activating transcription factor, which could activate the expression of target genes. Meanwhile, the expression of CtbZIP1 in S. cerevisiae mutant strain could increase the oil content and the total lipid content increased by 8% in transgenic Arabidopsis seeds. Therefore, it is speculated that CtbZIP1 plays an important role in increasing the oil content. This study will identify the gene expression pattern of CtbZIP1 at different developmental stages of safflower seeds by qRT-PCR and confirm the interaction during target genes in safflower. The function of CtbZIP1 in the process of oil synthesis will be researched and the synthesis mechanism will be analyzed. It lays the foundation for further exploration of the molecular mechanism of safflower oil accumulation.

红花是发展较快的新型油料作物之一，其应用前景广阔。我国红花种子的含油量远低于国外品种，在国际市场上缺乏竞争力，现有栽培技术不能大幅度提高籽油产量，难以填补红花籽油的市场缺口。通过基因调控方法提高油脂含量，培育高油红花品系已经成为迅速增加籽油产量的重要措施之一。课题组前期挖掘出红花油脂合成过程中显著上调的转录因子CtbZIP1；经验证CtbZIP1属于激活型转录因子且在酿酒酵母突变株和拟南芥种子中表达CtbZIP1，油脂含量均有所提高；由此证明CtbZIP1在油脂合成过程中起到重要作用。本课题在前期研究基础上，拟通过qRT-PCR方法，分析CtbZIP1在红花种子不同发育时期的表达模式；利用双分子荧光互补技术，明确CtbZIP1在红花体内与目标靶基因之间的互作关系；采取反向遗传学方法，确证CtbZIP1的作用，解析该蛋白在油脂合成过程中的调控机制，为深入探索红花油脂合成的分子机理奠定基础。

红花是发展较快的新型油料作物之一，应用前景广阔。本项目通过基因调控方法提高油脂含量，红花基因资源的有效挖掘为今后分子育种手段培育高油红花新品系奠定基础。课题组前期完成了红花基因组测序和转录物组测序数据库，红花的全长转录组测序产生了10.43 GB的数据，从中捕获了38,302个重复序列，完成了红花的从头转录组装配。基于Solexa的深度测序，挖掘出52个红花bZIP家族转录因子，通过生物信息学手段验证了该家族基因的结构特征以及进化分类，同时也推测了CtbZIP家族成员之间的互作关系和功能。基于此，我们以CtbZIP-G亚族和CtbZIP-S亚族基因为主要研究对象，通过qRT-PCR方法，明确了CtbZIP家族基因的时空表达模式，发现其在酵母菌株和植物种子中过表达该亚族基因，可以增加油脂含量；通过酵母互作实验也验证了CtbZIP各成员之间以及与其他转录因子之间的互作关系；通过超表达与突变体回补实验也验证了CtbZIP家族基因的功能，解析该蛋白在油脂合成过程中的调控机制，为深入探索红花油脂合成的分子机理奠定基础。