结缕草种子中NCED基因和CYP707A基因的克隆及其表达动态  

Cloning and Expression Dynamics of NCED and CYP707A Genes from Zoysia japonica Seeds

作　　者：迟晓雪[1] 孙洁峰 方程[1] 

机构地区：[1]中国农业大学草地研究所,北京100193 [2]青岛海源草坪有限公司,山东青岛266318

出　　处：《草地学报》2012年第1期146-151,165,共7页Acta Agrestia Sinica

基　　金：国家自然科学基金(30972137)资助

摘　　要：ABA是抑制种子萌发的主要激素,而9-顺式-环氧类胡萝卜素双加氧酶(NCED)和8’-羟化酶(CYP707A)是控制ABA合成及代谢的关键基因。为了解基因表达水平与种子萌发率之间的关系,以2种萌发率不同的结缕草(Zoysia japonica)海青一号(H1)和野生型(WT)结缕草种子为材料,克隆CYP707A基因目的片段,通过Real-timePCR测定2种结缕草种子在不同吸胀时间的NCED和CYP707A基因表达水平。结果表明:NCED和CYP707A基因在不同吸胀时间和不同材料中基因表达水平不同,在萌发率较高的海青一号(H1)种子吸胀过程中,NCED基因和CYP707A基因表达持续升高,在萌发率较低的野生型(WT)结缕草种子吸胀过程中NCED和CYP707A基因表达量先升高,随后又降低到较低水平,NCED基因和CYP707A基因在萌发率不同的2种结缕草种子吸胀过程中的表达存在差异,说明种子的萌发率不仅与ABA含量有关,还与ABA代谢速率有关,体现两者在影响种子萌发率过程中相互协作,相互平衡的关系。ABA is a major plant hormone inhibiting seed germination.Both 9-cis-epoxycarotenoid dioxygenase（NCED） and ABA 8＇-hydroxylase（CYP707A） are key genes involved in the biosynthesis and degradation processes of ABA.Correlation of seed germination rate and these two genes has been reported in many plant species,but few in herbage seeds.Two herbage seeds from Zoysia japonica-Haiqing1（H1） and wild type（WT） were used to study the relationship between seed germination rate and the expressions of these two genes.The gene CYP707A was cloned and the expression of both NCED and CYP707A in different materials under different imbibition regimes were determined through Real-time PCR.Both NCED and CYP707A had a continuous increasing trend in H1 with seed imbibition processing and had a relatively higher germination rate.However,the expressions of these two genes in WT with seed imbibition processing showed an increasing trend during the first 2 hours of imbibition then dropped to a very low level.The expression variances of these two genes suggest that there was a mutual coordination and balance relationship between ABA biosynthesis and degradation during seed germination.

关 键 词：结缕草 NCED基因 CYP707A基因 基因克隆 表达水平 

分 类 号：Q943.2[生物学—植物学]