【摘要】 浒苔(Ulva prolifera)作为黄海绿潮优势种,其自身具有极强的逆境适应能力。交替氧化酶(alternative oxidase,AOX)在植物逆境应答过程中扮演重要角色。为探索浒苔AOX蛋白的结构、功能与环境应答特征,应用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)对浒苔AOX基因(UpA OX)进行了克隆,并采用生物信息学方法进行了序列分析,同时探索了UpAOX基因在不同环境下的转录表达差异。结果表明:UpAOX基因的cDNA全长为2441 bp,编码236个氨基酸,具有典型的“EXXH”“EEE-Y”铁离子结合保守motif。AOX蛋白在进化过程中具有较强的保守性,尤其是C端;UpAOX基因中具备环境应激响应、生长发育、信号转导相关的顺式作用元件;实时荧光定量PCR实验结果表明,温度、干出、盐度、UVB逆境均与UpAOX基因转录表达量有显著关联。该研究结果为进一步深入挖掘UpAOX基因的生物学功能以及逆境响应策略提供了理论依据。更多还原

【Abstract】 As the dominant species of the green tide in the Yellow Sea, Ulva prolifera has strong adaptability to adversity. Alternative oxidase(AOX) plays an important role during plant stress response. To explore the structure,function, and environmental response characteristics of AOX in U. prolifera, the rapid amplification of cDNA ends(RACE) technique was used to characterize full-length AOX gene in U. prolifera(UpAOX), and bioinformatics wasused to analyze its sequence. At the same time, the differences in expression of AOX gene in U. prolifera under different environments were explored. The results showed that the full-length cDNA of AOX gene was 2 441 bp,which encoded 236 amino acids. AOX protein had typical “EXXH” and “EEE-Y” iron ion binding conserved motif.AOX protein had strong conservation during the evolution process, especially the C-terminal. AOX contained cis-acting elements related to environmental stress response, growth and development, and signal transduction. The real-time fluorescence quantitative PCR results indicated that temperature, desiccation, salinity, and UVB stresses were significantly correlated to AOX transcription. These results provided a theoretical basis for further exploring the biological function and stress regulation mechanism of AOX in U. prolifera.更多还原