摘要
樟树(Cinnamomum camphora(L.)Presl.)籽油富含中链脂肪酸,但其生物合成机制尚未可知。长链脂肪酰基CoA合成酶(long chain fatty aycl-CoA synthetases,LACSs)亚家族在植物脂肪酸合成与分解代谢中具有重要作用。以樟树转录组数据为参考、本研究克隆并鉴定了一个LACS基因亚家族成员,序列比对显示其编码氨基酸序列与拟南芥At LACS1序列相似性高达65%,故将之命名为Cc LACS1。实时荧光定量PCR检测显示Cc LACS1基因在花与种仁中优势表达,叶、茎组织中次之。缺陷型酵母互补实验证明Cc LACS1具有脂酰CoA合成酶活性,可广泛地将外源C10~C18脂肪酸活化为脂酰CoA硫酯,但C18类脂肪酸是其偏好催化底物。上述结果暗示Cc LACS1可能与樟树籽油合成与累积相关。
Seed oil of camphor tree（Cinnamomum camphora（L.） Presl.） contains high content of medium-chain fatty acid（ MCFA）, but the biosynthetic mechanism remains little understood. The subfamily of long chain aycl-CoA synthetases（LACSs） play the important roles in the synthesis and decomposition metabolism of fatty acid. Based on transcriptome data of C. camphora, the research identified and cloned a member of the LACS gene subfamily. Sequence alignment showed that its coding amino acid shared as high as 65% sequence similarity to At LACS1 of Arabidopsis thaliana, and therefore it was registered as Cc LACS1. Real-time fluorescent quantitative PCR analysis revealed Cc LACS1 was predo minantly expressed in both flower and kernel, followed by leaf and stem. Cc LACS1 was proved to have the synthetase activity of acyl-CoA in complementation test of deficient yeast mutant and could activate exogenous C10~C18 free fatty acids into fatty acyl-CoA thioesters, but C18 fatty acids were the preferred catalytic substrates. Thes e above results suggested that Cc LACS1 might be involve in the biosynthesis and accumulation of seed oil of camphor tree.
作者
汪信东
江香梅
章挺
伍艳芳
李江
Wang Xindong;Jiang Xiangmei;Zhang Ting;Wu Yanfang;Li Jiang(Institute of Camphor Tree,Jiangxi Academy of Forestry,Nanchang,330013)
出处
《分子植物育种》
CAS
CSCD
北大核心
2018年第16期5255-5264,共10页
Molecular Plant Breeding
基金
江西省科技计划项目(20143ACF60014)
江西省林业科学院青年人才培养项目(2014521102)共同资助
关键词
樟树
长链脂肪酰基CoA合成酶1
组织表达特异性
酵母互补检测
底物偏好性
Camphor tree
Long chain fatty aycl-CoA synthetase 1
Tissue-specific expression
Yeast comptemen-tation test
Substrate preference
