【摘要】 为了探究FAD2在花生低温响应中的作用,本研究从普通油酸花生中花16 (ZH16)和高油酸花生中花413 (ZH413)中克隆得到花生AhFAD2家族的全部基因,共7个。通过分析这些基因的表达模式发现,在ZH16和ZH413中各FAD2基因表达模式相似, AhFAD2-1A/B主要在花和发育的种子中表达, AhFAD2-3A/B主要在营养组织中表达, AhFAD2-4A/B主要在根和花中表达,表明AhFAD2基因在花生不同发育阶段和不同组织中发挥各自的生物学功能。在15℃下发芽6 d发现,ZH413的发芽率未显著下降,而ZH16的发芽率显著下降。种子萌发过程中,AhFAD2-1A/B和AhFAD2-4A/B均受低温诱导表达。在ZH16中AhFAD2-1A/B在低温诱导第6天开始显著上调表达,而在ZH413中第1天显著上调表达;在ZH16中AhFAD2-4A/B在低温诱导第3天出现显著上调表达,之后表达量下降,但在ZH413中第1天就显著上调表达,且始终维持在高水平表达。基于以上研究结果推测,高油酸花生在受到低温胁迫时,AhFAD2-1A/B编码蛋白失活,但AhFAD2-4A/B的高量表达在一定程度上弥补了这部分功能。同时也说明AhFAD2-1A/B功能的缺失并不是决定花生耐寒性的主要因素。本研究的开展为培育抗寒的高油酸花生品种奠定了理论基础,为高油酸花生在高纬度、高海拔地区推广提供了理论支持。更多还原

【Abstract】 To explore the roles of FAD2s in response to cold stress in peanut, we cloned seven Ah FAD2 genes from normal oleate peanut ZH16 and high oleate peanut ZH413, respectively. The results of qRT-PCR showed that the expression patterns of FAD2 genes were similar in ZH16 and ZH413. AhFAD2-1 A/B was highly expressed in flower and developing seed, AhFAD2-3 A/B was mainly expressed in leaf and stem, and AhFAD2-4A/B was expressed specifically in root and flower, indicating that Ah FAD2 genes played their respective roles in different developmental stages and tissues of peanut. At 6 days after inducing under 15℃, the germination rate of ZH16 was significantly decreased while that of ZH413 was not significantly affected. The expression of both AhFAD2-1 A/B and AhFAD2-4 A/B were induced by cold stress. The expression of AhFAD2-1A/B was significantly up-regulated at 6 DAI in ZH16, while at 1 DAI in ZH413, suggesting that AhFAD2-1A/B was induced by cold more quickly in high oleate peanut. Furthermore, the expression of Ah FAD2-4A/B was significantly up-regulated at 3 DAI in ZH16 and then decreased, while it was increased immediately and maintained at high level for six days in ZH413. Based on these results, we speculate that up-regulation of AhFAD2-4 A/B may compensate the function of AhFAD2-1A/B that is deactivated under cold stress in high oleate peanut, and the deactivation of AhFAD2-1A/B is not the most important factors affecting peanut cold tolerance. This study provides a theoretical basis in breeding of high oleate peanut with high tolerance to cold stress, and the theoretical support for extension of high oleate peanut in both high latitude and high altitude regions.更多还原