摘要
γ-氨基丁酸(GABA)是一种四碳非蛋白质氨基酸,具有降血压等功能。为提高稻米中GABA含量,利用RNA干扰技术,构建水稻中GABA代谢关键酶GABA转氨酶1基因(Os GABA-T1)的干扰载体,通过农杆菌介导法,将其转化至粳稻品种宁粳1号中。实时荧光定量PCR检测结果表明导入的RNA干扰结构成功地降低了目的基因Os GABA-T1的表达,且干扰家系中Os GABA-T2基因表达也随之下降。对转基因T3代稻米GABA含量测定发现,糙米中GABA含量相对于对照增加了13倍以上,精米中GABA含量也显著增加,而其他主要氨基酸含量则没有明显变化。测定储藏4个月的转基因稻米发现,GABA含量仍具有较高水平。所以,利用RNA干扰技术可有效提高稻米γ-氨基丁酸(GABA)含量,为培育富含GABA的降血压功能性水稻品种提供基础。
γ-Aminobutyric acid （GABA） is a four-carbon non-protein amino acid and has been identified to have a function in reducing blood pressure. In order to increase GABA contents in rice grains, we constructed a RNA interference （RNAi） vector suppressing the expression of GABA transaminase 1 gene （OsGABA-T1）. GABA transaminase is a key enzyme that converts GABA to succinate semialdehyde （SSA）. The RNA interference vector was transformed into the callus of japonica cv. Ningjing 1. qRT-PCR analysis showed that OsGABA-T1 transcript abundance in the RNAi transgenic lines was effectively reduced, so did the homolog gene OsGABA-T2. The GABA contents of brown rice in T3 generation of RNAi lines were 13 times higher than these in Ningjing 1, so did in polished rice as well as brown rice and polished rice stored for four months of post-harvest in transgenic rice, while other main amino acid contents did not change much. In summary, this research provides a basis for breeding a rice variety which could contribute to reduce blood pressure due to the enrichment of GABA contents in rice seeds though effectively suppressing the expression of OsGABA-T1 gene by the RNA interference technique.
出处
《作物学报》
CAS
CSCD
北大核心
2015年第9期1305-1312,共8页
Acta Agronomica Sinica
基金
国家转基因生物新品种培育重大科技专项(2014ZX08001006)
农业部长江中下游粳稻生物学与遗传育种重点实验室
长江流域杂交水稻协同创新中心
江苏省植物基因工程技术研究中心
江苏省现代作物生产协同创新中心资助
