拟南芥与油菜种子油脂积累消减器(SFAR)对含油量形成的影响及分子机制

To increase seed fatty acid content, many efforts has been made on the promotion of effective lipid biosynthesis, but little attention has been paid on the decrease of lipid dehydrolysis in the dynamic process of oil accumulation. Recently, we named Seed Fatty Acid Reducers (SFARs) and reported their function that negatively regulates the accumulation of seed fatty acid (FA). In a broad sense, SFARs are defined as a group of genes that decompose seed fatty acids during seed development. In a narrow sense, SFARs mean a kind of GDSL type lipase hydrolyzing triacylglycerol (TAG). Although we understood the function of SFAR1 to SFAR5 and their upstream regulatory factors in Arabidopsis, the function of the rest 103 SFARs, not mention the 140 SFAR homologs in the A genome of rapeseed, are not known. In this study, we aim to systemically clone SRAFs from Arabidopsis and oilseed rape, investigate and compare their nucleotide and amino acid sequences, their expression patterns during plant development, and the upstream regulators; exlore the effects of loss-of-function and/or gain-of-function of single sfar locus, on seed fatty acid accumulation; scan certain SFAR loci in a rapeseed EMS-induced mutant population for loss-of-function mutations, homogenize the genetic background of the mutants by backcrossing, and pyramid the loss-of-function sfars at multiple loci, referring the knowledge from Arabidopsis.

提升种子含油量的努力以往大都放在促进油脂的有效合成上，而降低油脂积累动态过程中的消减，尚未被足够重视，却可能是实现含油量大幅提升的另一突破口。SFAR是我们实验室近年命名并发表的一类基因，泛指种子油脂积累负向调控因子，狭义地指水解TAG的GDSL类脂酶基因。我们曾系统地研究与报道了SFAR1至SFAR5对种子油脂积累的消减作用及其上游调控信号，但对拟南芥其余103个SFAR基因，及油菜A基因组约140个SFAR基因缺乏了解。这项课题旨在系统地克隆拟南芥与油菜SFAR基因；比较这两个十字花科近缘物种中SFARs的序列特点、时空表达特征、上游调控机制、及生理功能的异同；探明各类SFAR突变对拟南芥种子含油量的影响，选择部分作用明显的SFAR位点，在油菜EMS诱变群体中检测缺失性突变引起的种子含油量变化、通过回交、聚合等手段获得多个SFAR位点上同时丧失功能的育种材料，并研究其脂肪酸积累特征。

提升种子含油量的努力以往大都放在促进油脂的有效合成上，而降低油脂积累动态过程中的消减，尚未被足够重视，却可能是实现含油量大幅提升的另一突破口。SFAR是我们实验室近年命名并发表的一类基因，泛指种子油脂积累负向调控因子，狭义地指水解TAG的GDSL类脂酶基因。我们曾系统地研究与报道了SFAR1至SFAR5对种子油脂积累的消减作用及其上游调控信号，但对拟南芥其余103个SFAR基因，及油菜A基因组约140个SFAR基因缺乏了解。这项课题旨在系统地克隆拟南芥与油菜SFAR基因；比较这两个十字花科近缘物种中SFARs的序列特点、时空表达特征、上游调控机制、及生理功能的异同；探明各类SFAR突变对拟南芥种子含油量的影响，选择部分作用明显的SFAR位点，在油菜EMS诱变群体中检测缺失性突变引起的种子含油量变化、通过回交、聚合等手段获得多个SFAR位点上同时丧失功能的育种材料，并研究其脂肪酸积累特征，通过4年的研究工作，我们圆满完成了上述主要研究内容，发表了5篇SCI论文，应邀作国际会议大会报告4次，获得了一项教育部自然科学二等奖成果，培养了5名博士研究生、4名硕士研究生。