木质部特异表达杨树PtoMYB148转录因子克隆与分析  

Isolation and Characterization of PtoMYB148 Transcription Factor Expressing Preferentially in Developing Xylem in Populus tomentosa

作　　者：程占超 陈亚娟[2] 张杰伟[2] 王宏芝[2] 魏建华[2] 

机构地区：[1]北京农学院,北京102206 [2]北京农业生物技术研究中心,北京100097

出　　处：《生物技术通报》2013年第11期69-74,共6页Biotechnology Bulletin

基　　金：国家高技术研究发展计划"863项目"(2011AA100201);国家重点基础研究发展计划"973项目"(2012CB114501)

摘　　要：作为植物中最大的转录因子家族之一,MYB转录因子在次生壁合成转录调控过程中发挥重要的作用。详细解析杨树不同MYB转录因子对次生细胞壁中纤维素、半纤维素和木质素等主要成分合成的调控作用,有利于在杨树定向生物技术育种中制定实用有效的分子设计策略。主要以毛白杨为材料,克隆了毛白杨PtoMYB148转录因子的全长cDNA。通过植物细胞显微切割结合荧光定量PCR技术检测基因转录表达水平,显示PtoMYB148在分化的木质部及成熟木质部高水平表达。系统进化分析表明,PtoMYB148与拟南芥AtMYB103、AtMYB050和AtMYB086转录因子相似性较高,其中AtMYB103已被证明参与次生细胞壁合成调控。亚细胞定位试验表明,PtoMYB148定位于细胞核内。PtoMYB148在酵母细胞中具有转录激活活性。PtoMYB148是具有活性的转录因子,可能在毛白杨次生细胞壁的合成中起重要作用。As one of the plant＇ s largest transcription factor families, MYB transcription factors play important roles in transcriptionally regulating the synthesis of secondary cell wall, which is composed of cellulose, hemicellulose, and lignin. By uncovering transcription factors regulating secondary cell wall biosynthesis, it may be possible to develop novel strategies for genetic improvement of wood. In this study, the full- length PtoMYB148 cDNA was cloned in Populus tomentosa. PtoMYB148 exhibited a high level of expression in the developing and mature xylem. Phylogenetic analysis showed that PtoMYB148 was closely related to AtMYB103, AtMYB050 and AtMYB086 from Arabidopsis, among which AtMYB103 was shown to regulate secondary cell wall synthesis. Yellow fluorescent protein （ YFP ） -tagged fusions of PtoMYB148 was found to be targeted to the nucleus when expressed in Arabidopsis leaf protoplasts. Transcriptional activation analysis demonstrated that PtoMYB148 was able to activate the expression of the His3 and 13-Gal reporter genes in yeast. Taken together, these findings showed that PtoMYB148 functions as a transcription factor, and that it may play roles during wood formation in Populus.

关 键 词：转录因子 次生细胞壁 转录激活 亚细胞定位 

分 类 号：S792.11[农业科学—林木遗传育种]