地黄块根膨大发生和驱动的组织观察及激素相关基因的调控分析  

Observation of prime position and driving zones in process of tuberous root expanding and expression analysis of phytohormone relative genes in Rehmannia glutinosa

作　　者：王鹏飞[1] 李鑫宇[1] 李明杰[1] 刘林[2] 王潇然[1] 王丰青[1] 李春奇[1] 陈新建[1] 张重义[3] 

机构地区：[1]河南农业大学生命科学学院,河南郑州450002 [2]临沂大学生命科学学院,山东临沂276000 [3]福建农林大学中药材GAP研究所,福建福州350002

出　　处：《中国中药杂志》2014年第17期3245-3253,共9页China Journal of Chinese Materia Medica

基　　金：国家自然科学基金项目(31271674,81274022);高等学校博士学科点专项科研基金项目(20123515110005)

摘　　要：目的:为了研究地黄块根膨大的发育特征,揭示激素相关基因在这个过程中的调控作用机制。方法:该研究以地黄品种"温-85"为实验材料,采集不同发育时期的地黄块根进行表型观察,利用半薄树脂切片技术观察块根的组织形态。从地黄转录组数据库中挑选与激素合成和响应相关的基因,利用qRT-PCR技术研究激素相关基因在地黄不同发育时期块根组织中的表达变化。结果:地黄的发育阶段可划分为苗期、拉线期、块根膨大初期,膨大中期,膨大后期和成熟期。块根解剖学特征分析表明次生形成层的分裂启动了地黄块根膨大的进程;膨大前期次生形成层的持续快速分裂和副形成层的形成驱动了块根的向外(平周)和侧向(圆周)持续快速膨大。在半薄和超薄切片观察过程中发现在地黄块根中存在有大量的油脂细胞。定量结果分析显示IAA,CK,ABA,乙烯,JA,EB的合成和响应基因整体呈现上调表达趋势,GA的合成与响应基因呈下调趋势,其负调控因子基因则上调表达。大部分激素合成相关基因的表达高峰期处在拉线期、膨大前期。结论:拉线期和块根膨大前期是地黄块根发育最为关键的时期,IAA,CK,ABA,乙烯,JA,EB的合成和响应基因的上调与GA合成基因的下调能促进块根的发育。油脂细胞可能与地黄药用成分的合成与储存有密切关系。该研究为阐述地黄块根发育的规律和分子调控机制进行了有益的探索。In order to study the development characteristics of Rehmannia glutinosa tuberous root expansion and reveal the regulation mechanism of the genes related to hormones in this process, R. glutinosa ＂wen-85＂ was used as the experimental material in this study. IL glutinosa tuberous roots of different developmental stages were collected to observe phenotype and tissue morphology using resin semi-thin sections method. The genes related to hormone biosynthesis and response were chosen from the transcriptome of R. glutinosa, which was previously constructed by our laboratory, their expression levels at different development stages were measured by real-time quantitative PCR. The results showed that the root development could be divided into six stages： seeding, elongation, pre-expanding, mid-expanding, late-ex- panding and maturity stage. The anatomic characteristics indicated that the fission of secondary cambium initiated the tuberous root expan- sion, and the continuous and rapid division of secondary cambium and accessory cambium kept the sustained and rapid expansion of tuberous root. In addition, a large number oleoplasts were observed in root on the semi-thin and ultra-thin section. The quantitative analysis suggested that the genes related to biosynthesis and response of the IAA, CK, ABA,ethylene ,JA and EB were up-regulated expressed, meanwhile, GA synthesis and response genes were down-regulated expressed and the genes of GA negative regulation factors were up-regulated expressed. The maximum levels of most genes expression occurred in the elongation and pre-expansion stage, indicating these two stages were the key periods to the formation and development of tuberous roots. Oleoplasts might be the essential cytological basis for the formation and storage of the unique medicinal components in R. glutinosa. The results of the study are helpful for explanation of development and the molecular regulation mechanism of the tuberous root in R. glutinosa.

关 键 词：地黄 块根发育 切片 激素 基因表达 

分 类 号：S567.239[农业科学—中草药栽培]