花叶矢竹叶绿体psbD基因的克隆与功能分析  

Cloning and functional analysis of the psbD gene in Pseudosasa japonica f. akebonosuji

作　　者：许冰清[1] 安苗苗[1] 姜可以[1] 徐丽丽[1] 杨海芸[1] 周明兵[1] 

机构地区：[1]浙江农林大学亚热带森林培育国家重点实验室培育基地,浙江临安311300

出　　处：《浙江农林大学学报》2015年第4期557-565,共9页Journal of Zhejiang A&F University

基　　金：国家自然科学基金资助项目(31170565;31270645;31470615);浙江省自然科学基金资助项目(LR12C16001;LY12C16002)

摘　　要：植物叶绿体光系统Ⅱ是植物进行光能转化、水的裂解和释放氧气的重要蛋白复合物,psb D基因编码光系统Ⅱ(PSⅡ)作用中心蛋白D2,D2和D1构成的异源二聚体上结合着与电子传递有关的大部分辅助因子和色素分子。以花叶矢竹Pseudosasa japonica f.akebonosuji为材料,提取总DNA,聚合酶链式反应(PCR)扩增psb D基因全长序列(Pj-psb D)。序列分析表明:其开放阅读框(ORF)为1 059 bp,编码352个氨基酸,相对分子质量为39.59 k D,等电点为5.34,有6个跨膜结构,有别于高等植物中psb D蛋白普遍存在的5个跨膜区。psb D还具备有多个与光合作用有关的结构域和功能位点。本实验用荧光定量PCR技术检测了花叶矢竹叶片3个不同生长阶段和3种叶色中psb D基因的表达量。分析表明:在花叶矢竹叶片生长发育时期,为了满足叶片生长发育和叶绿体的形成的需要,psb D基因表达量逐步提高。研究还发现:psb D在白叶中的表达量显著高于绿叶,这可能与植物的光保护机制有关,降低强光对白色和部分白叶的光合系统的损伤。Photosystem Ⅱ（PSⅡ） of a plant chloroplast is an important protein complex in light-dependent reactions of oxygenic photosynthesis with the psbD gene encoding the center protein D2. Until now, psbD gene in Pseudosasajaponica f. akebonosuji still would not been sequenced and reported. In order to analysis the psbD gene structure and the potential relation of psbD gene function and leaf color variation, in this study the ge- nomic DNA of Pseudosasa japonica f. akebonosuji was extracted and the full-length psbD gene sequence Pj- and albino leaves of P. japonica f. akebonosuji leaves with three material replicates and three expriements replicates. Results showed that the Open Reading amino acids with a relative molecular weight of Frame （ORF） of Pj-psbD was 1 059 bp long encoding 352 39.59 kD and an isoelectric point of 5.34. In the Pj-psbD polypeptide chain, there were six transmembrane domains, plus multiple photosynthesis domains and other function sites. Among the three colors of leaves the psbD expression level in the three growth stages of the al- bino leaves was highest with more than 2-4 times than those of the according three growth stages of the green leaves. The continuously increasing expression levels of the gene along with leaf growth and development for the three types of leaves could meet the formation needs of the chloroplast, and the high psbD expression level in the albino leaf could be the protection mechanism that inhibits light damage in the photosynthetic system.

关 键 词：分子生物学 花叶矢竹 psbD基因 克隆 叶色变异 荧光定量聚合酶链式反应(q RT-PCR) 

分 类 号：S795[农业科学—林木遗传育种] Q786[农业科学—林学]