甘薯细胞色素P450单加氧酶基因IbCYP714E1和IbCYP714E2的鉴定及表达分析

CYP714基因在植物赤霉素合成与代谢过程中发挥着重要作用。该研究从甘薯基因组中鉴定出2个CYP714基因,对基因的结构和编码蛋白质的理化性质等进行了生物信息学分析,并利用荧光定量PCR(qRT-PCR)技术分析基因在不同组织和非生物胁迫条件下的表达特征,为解析甘薯CYP714基因的生物学功能提供帮助。结果表明:(1)2个基因为分别编码518个和521个氨基酸的碱性亲水蛋白,被亚细胞定位于细胞质中;(2)2个蛋白质均含有CYP714蛋白亚家族的3个特征结构域,与毛白杨的PtCYP714E2、PtCYP714E4和PtCYP714E5蛋白聚为一类,分别定名为IbCYP714E1和IbCYP714E2;(3)荧光定量PCR分析显示,IbCYP714E1和IbCYP714E2基因的表达部位存在一定差异,IbCYP714E1在柴根、初生根和叶片中表达量较高,而IbCYP714E2基因只在柴根和花上表达量较高,在盐和干旱胁迫下,IbCYP714E1基因表达量均增加,而IbCYP714E2基因只在盐胁迫条件下表达量增加。IbCYP714E1和IbCYP714E2基因可能参与赤霉素的降解和对非生物胁迫的应答。

Identification and Expression Analysis of the Cytochrome P450 Monooxygenase Genes IbCYP714E1 and IbCYP714E2 in Sweet Potato

The CYP714 gene plays an important role in the synthesis and metabolism of gibberellin in plants. In this study, two CYP714 genes were identified from the sweet potato genome, and the structure of the genes and the physical and chemical properties of the coding protein were analyzed by bioinformatics. The expression characteristics of the genes under different tissues and abiotic stress conditions were analyzed by fluorescence quantitative PCR (qRT-PCR) technology, which helped to analyze the biological function of the sweet potato CYP714 gene. The results showed: (1) The two genes encode basic hydrophilic proteins of 518 and 521 amino acids, which were subcellularly localized in the cytoplasm. (2) Both proteins contain three characteristic domains of the CYP714 protein subfamily, which were clustered with PtCYP714E2, PtCYP714E4, and PtCYP714E5 proteins of Populus tomentosa, and were named IbCYP714E1 and IbCYP714E2, respectively. (3) Fluorescence quantitative PCR analysis showed that there were certain differences in the expression sites of IbCYP714E1 and IbCYP714E2 genes. The expression of IbCYP714E1 was higher in Chai root, primary root and leaf, while the expression of IbCYP714E2 gene was higher only in Chai root and flower. Under salt and drought stresses, the expression of IbCYP714E1 gene increased, while the expression of IbCYP714E2 gene increased only under salt stress. The IbCYP714E1 and IbCYP714E2 genes may be involved in the synthesis and degradation of gibberellin and the response to abiotic stress.