亚麻LuACL-1基因对拟南芥油脂积累和胁迫响应的影响  

Effects of Flax LuACL-1 Gene on Oil Accumulation and Stress Response in Arabidopsis thaliana

作　　者：刘佳佳[1] 李雨欣 何铭渊 崔晓辉 马芸芸 刘子金 陈明训 郭媛[1] LIU Jiajia;LI Yuxin;HE Mingyuan;CUI Xiaohui;MA Yunyun;LIU Zijin;CHEN Mingxun;GUO Yuan(College of Agronomy,Northwest A&F University,Yangling Shaanxi 712100,China)

机构地区：[1]西北农林科技大学农学院,陕西杨凌712100

出　　处：《西北农业学报》2024年第12期2315-2327,共13页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家科技创新2030(2022ZD04010);陕西省科技创新团队(2024RS-CXTD-69);中央高校基本科研业务费专项资金(2452023090)。

摘　　要：ATP-柠檬酸裂解酶(ATP-citrate lyase,ACL)在种子油脂积累和胁迫响应中发挥着重要作用,但是目前亚麻ACL(LuACL)在这些过程中的功能尚不明确。以‘陇亚10号’为材料克隆LuACL-1全长编码序列并转化拟南芥,分析其在种子油脂积累和非生物胁迫响应中的功能。结果表明,在拟南芥野生型背景下异源表达LuACL-1使种子变大,种子质量增加,同时通过正调控与油脂合成相关基因AtPKp-α、AtKASⅢ、AtFAE1和AtGPAT1的表达促进种子油脂积累。此外,在NaCl和甘露醇胁迫下,转基因株系种子萌发率显著高于野生型,其AtNCED3、AtEM1和AtEM6的表达量均显著低于野生型;同时,超氧化物歧化酶、过氧化物酶活性显著升高,过氧化氢、超氧阴离子和丙二醛含量降低。综上所述,LuACL-1不仅可以通过上调油脂合成相关基因的表达促进种子油脂积累,还可以通过提高活性氧清除能力、减轻细胞膜损伤,调控ABA合成和信号响应基因的表达增强拟南芥对盐胁迫和渗透胁迫的耐受能力。ATP-citrate lyase(ACL)plays a crucial role in seed oil accumulation and stress response,however,the involvement of its homolog(LuACL)from flax(Linum usitatissimum L.)in these processes remains unclear.In this study,the full-length coding sequence of LuACL-1 was cloned from‘Longya 10’and transformed into Arabidopsis thaliana to analyze its function in seed oil accumulation and abiotic stress response.The results showed that heterologous expression of LuACL-1 in Arabidopsis wild-type background enhanced seed size and seed mass,and promoted seed oil accumulation by positively regulating the expression of oil biosynthesis related genes,including AtPKp-α,AtKASIII,AtFAE1 and AtGPAT1.In addition,under NaCl and mannitol stress,the germination rate of LuACL-1 transgenic lines was significantly higher than that of wild-type,while the expression levels of AtNCED3,AtEM1 and AtEM6 were significantly lower.Consistently,the activities of superoxide dismutase and peroxidase significantly increased in LuACL-1 transgenic lines,alongside decreased levels of hydrogen peroxide,superoxide anion,and malondialdehyde.In conclusion,the heterologous expression of LuACL-1 in Arabidopsis not only promotes seed oil accumulation by upregulating the expression of genes related to oil biosynthesis but also enhances the salt and osmotic stress tolerance by improving the active oxygen scavenging capacity,reducing membrane lipid damage,and regulating the expression of ABA synthesis and signaling response genes.The results of this study provide genetic resources and molecular references for improving future breeding of flax and other oil crops with high oil content and enhanced abiotic stress.

关 键 词：亚麻 ATP-柠檬酸裂解酶 脂肪酸 NACL胁迫 甘露醇胁迫 

分 类 号：S565.9[农业科学—作物学]