蝴蝶兰Rubisco活化酶基因PhRCAα的序列特征及在低温胁迫下的表达分析  

Characterization of Rubisco Activase Gene PhRCAα from Phalaenopsis and Its Expression under Low Temperature

作　　者：袁秀云[1] 许申平[1] 王洁琼[2] 崔波[1] 

机构地区：[1]郑州师范学院生物工程研究所,郑州450044 [2]河南农业大学生命科学学院,郑州450002

出　　处：《分子植物育种》2016年第4期835-843,共9页Molecular Plant Breeding

基　　金：河南省重点科技攻关项目(092102110128);河南省教育厅科技攻关项目(14B180036)共同资助

摘　　要：为研究蝴蝶兰Rubisco活化酶基因(RCA)及其在低温胁迫下的响应机制,本研究利用RT-PCR及RACE技术从蝴蝶兰叶片中克隆了一个Rubisco活化酶基因PhRCAα的c DNA序列(登录号KU187968)该基因全长1 642 bp,编码473个氨基酸,包含P-loop_NTPase超家族结构域,预测其成熟蛋白的分子质量为46.16 k D,等电点为5.73,属于RCA基因的α亚基。实时荧光定量PCR分析显示,在13℃/8℃的昼夜温度条件下,蝴蝶兰PhRCAα基因的转录表达在处理3 d、6 d、9 d和15 d时明显下降,恢复正常温度条件后,该基因的表达升高;在4℃低温条件下,PhRCAα基因的转录表达在处理0.5 h、1 h和2 h内逐渐升高,而在处理4 h时其表达量下降,一直到低温处理48 h时,其表达量维持在较低水平。结果表明PhRCAα对驯化低温(13℃/8℃)和冷胁迫(4℃)具有不同的响应机制,PhRCAα对短期的冷胁迫有一定的防御作用。To study the sequen ce of RC A gene from Phalaenopsis and to clarify the responding mechanism of Phalaenopsis under low temperature, a full-length c DNA of Rubisco activase gene PhRCAα(Gen Bank accession number: KU187968) was cloned from leaf of Phalaenopsis using RT-PCR combined with RACE techniques. This sequence consisted of 1 642 bp, encoding a mature polypeptide of 473 amino acids with a domain of P-loop_NTPase super-family. The molecular mass and theoretical isoelectric point of the protein were around 46.16 k D and 5.73 respectively. The gene belonged to the alpha subunit of RCA gene. The results of real-time fluorescent quantitative PCR showed that the transcript levels of PhRCAα in Phalaenopsis were decreased significantly under day/night 13℃/8℃ for 3 d、6 d、9 d and 15 d, then increased after the recovering to normal temperature. Under the cold stress of 4℃, the expressions of PhRCAα were increased gradually at 0.5 h, 1 h and 2 h, then decreased at 4 h of cold stress to lower level than before treatment, the lower transcript level continued to 48 h of cold stress. The results showed that the PhRCAα had different responding mechanism to cold acclimation(13℃/8℃) and cold stress(4℃). PhRCAα played a regulatory role in short-term cold resistance.

关 键 词：蝴蝶兰 RUBISCO活化酶 低温胁迫 表达分析 

分 类 号：S682.31[农业科学—观赏园艺]