摘要
光合系统Ⅰ亚基O(PhotosystemⅠsubunit O,Psa O)是光合系统Ⅰ中的蛋白亚基,在两个光合系统之间平衡激发能方面起着重要的作用.为研究Psa O基因的结构和功能,对甘蔗(Saccharum offi cinarum L.)叶片全长c DNA文库进行测序,获得光合系统Ⅰ亚基O基因的全长c DNA序列,命名为Sc Psa O(Gen Bank Accession Number:KF714498).生物信息学分析表明,该基因全长708 bp,开放阅读框435 bp,编码144个氨基酸;该基因所编码的蛋白定位于叶绿体基质,无信号肽,为疏水性非分泌碱性蛋白,二级结构多为无规则卷曲,含有PJN00046家族的保守结构域,参与能量新陈代谢及脂肪酸新陈代谢.同时,该基因在不同物种间具有较强的保守性,其中与同属C4植物的同源性较C3植物高.荧光定量PCR分析结果表明,甘蔗Sc Psa O基因在叶片中的相对表达量最高,具有一定的组织特异性;在氯化钠(Na Cl)、聚乙二醇(PEG)、氯化铜(Cu Cl2)、脱落酸(ABA)、水杨酸(SA)和茉莉酸甲酯(Me JA)等外源胁迫下,其表达量均呈下调趋势,且以PEG胁迫下的下调表现最为明显.这些结果表明这几种外源胁迫可能抑制甘蔗Sc Psa O基因的转录水平表达,为其进一步功能验证以及在甘蔗基因工程中的应用积累了基础资料.
Photosystem I subunit O （PsaO） is a protein subunit of photosystem I and plays an important role between twophotosystems. To study the structure and function of PsaO gene, the full-length cDNA sequence of PsaO gene was obtained from sugarcane （Saccharum officinarum L.） leaf full-length cDNA library through sequencing, validated by bioinformatics analysis, and named ScPsaO （GenBank Accession Number： KF714498）. The full length ofScPsaO gene was 708 bp, containing 435 bp open read frame （ORF）, and encoding 144 amino acids residues. Based on the predicted analysis of bioinformatics, the hydrophobic non-secretory basic protein located in chloroplast stroma ScPsaO has a conserved functional domain belonging to PJN00046 superfamily. Its secondary structure elements are mainly random coil. This protein without signal peptide mainly participates in metabolism of energy and fatty acid. The ScPsaO gene is highly conservative in different plant species, especially in C4 plants. Real-time quantitative PCR analysis showed definite tissue specificity of the expression ofScPsaO gene, and a trend to be down-regulated under different abiotic exogenous stresses including NaC1, PEG, CuC12, ABA, SA and MeJA. Among them, PEG stress down-regulated the gene most significantly. These results demonstrated that the transcriptional level ofScPsaO gene could be inhibited by these exogenous factors, which laid the foundation for its further function validation and its application in sugarcane genetic engineering.
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2015年第2期208-214,共7页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金项目(31340060)
福建省高等学校新世纪优秀人才支持计划项目(JA14095)
现代农业产业技术体系建设专项资金项目(CARS-20)资助~~
作者简介
通讯作者Correspondingauthor（E—mail：queyouxiong@126．com）
