《植物生理学报》 2015, 51(5): 668-678

种子特异表达二酰甘油酰基转移酶基因(VgDGAT1)提高亚麻荠种子油脂积累

苑丽霞^1,2, 毛雪¹, 高昌勇¹, 张莉¹, 薛金爱¹, 杨致荣¹, 李润植^1,*

¹山西农业大学分子农业与生物能源研究所, 山西太谷030801; ²晋中学院生物科学与技术学院, 山西晋中030600

通信作者：李润植；E-mail: rli2001@hotmail.com；Tel: 0354-6288374

摘　要：

亚麻荠(Camelina sativa)是一种“低耗、高效、环保”的非粮型工业油料作物。为提高亚麻荠种子含油量, 将来源于一种菊科野生油料植物(Vernonia galamensis)高酶活性的二酰甘油酰基转移酶1 cDNA克隆(VgDGAT1)在发育种子中特异表达。VgDGAT1超表达导致转基因亚麻荠种子中DGAT酶活性提高了30多倍。VgDGAT1高表达的亚麻荠种子含油量从野生型的37%提高到46%~51%, 而且蛋白质积累未减少, 表明对DGAT酶基因进行遗传修饰可打破种子油和蛋白含量的负相关连锁。此外, VgDGAT1高表达也没有对种子重量和种子萌发等农艺性状造成不良影响。这种高油亚麻荠基因工程新种质可进一步用于商业化优良新品种的培育。

关键词：亚麻荠; 二酰甘油酰基转移酶(DGAT); 种子特异表达; 种子油脂合成积累

收稿：2015-03-06   修定：2015-03-30

资助：国家自然科学基金(30971806、31201266和31401430)、国家“948”项目(2014-Z39)和山西省煤基重点科技攻关项目(FT-2014-01)。

Seed-Specific Over-Expression of a Diacylglycerol Acyltransferase 1 Gene (VgDGAT1) Increase Seed Oil Accumulation in Camelina sativa

YUAN Li-Xia^{1, 2}, MAO Xue¹, GAO Chang-Yong¹, ZHANG Li¹, XUE Jin-Ai¹, YANG Zhi-Rong¹, LI Run-Zhi^1,*

¹Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, Shanxi 030801, China; ²College of Biological Science and Technology, Jinzhong University, Jinzhong, Shanxi 030600, China

Corresponding author: LI Run-Zhi; E-mail: rli2001@hotmail.com; Tel: 0354-6288374

Abstract:

Camelina sativa is an important non-food industrial oilseed with “low-input, high efficiency and environment-friendly”. To enhance seed oil content for meeting an increasing market demand, a cDNA clone (Vg-DGAT1) encoding type 1 diacylglycerol acyltransferase from Vernonia galamensis with the higher DGAT enzymatic activity was introduced into camelina by Agrobacterium-mediated floral dip infiltration. Seed-specific over-expression of VgDGAT1 significantly enhanced the DGAT activity in the transgenic seeds by 30 folds more compared to the wild-type control, resulting in seed oil content increase from 37% (dry weight) in the wild-type seeds up to 46%–51% in the transgenics. However, seed protein level was not significant difference between the transgenic and the wild type, indicating that genetic modification on DGAT can break up the negative genetic linkage of oil and protein contents in seeds. Moreover, the seed-specific high expression of Vg- DGAT1 did not adversely affect seed weight, seed germination and other agronomic traits. Such novel engineered camelina lines with higher seed oil content and no reduction of protein accumulation could be used for breeding new camelina varieties with multiple excellent agronomic traits for commercialization.

Key words: Camelina sativa; diacylglycerol acyltransferase (DGAT); seed-specific expression; seed oil synthesis and accumulation