College of Life Science and Technology, Central South University of Forestry and Technology, Hunan Changsha, 410004, China.
Bangor College China, a Joint Unit of Bangor University and Central South University of Forestry and Technology, Hunan Changsha, 410004, China.
Funct Integr Genomics. 2023 Aug 21;23(3):277. doi: 10.1007/s10142-023-01214-w.
The precise biological function and activity of the deoxylulose-5-phosphate reductoisomerase (DXR) gene and its promoter in Osmanthus fragrans var. semperflorens remain unclear, even though OfDXR is known as the crucial enzyme involved in plant terpenoid synthesis. This study aimed to shed light on the role and activity of the OfDXR gene and its promoter in O. fragrans var. semperflorens by employing RACE-PCR and Hi-TAIL-PCR techniques for the cloning of the gene and promoter sequence from the petal tissue. Subsequently, genetic transformation and histochemical staining methods were utilized to analyze their function and activity. The OfDXR gene exhibited a DNA sequence length of 5241 bp, encompassing 12 exons and 11 introns. The corresponding cDNA sequence of the OfDXR gene was 1629 bp, encoding 474 amino acid residues. Expression analysis revealed that the OfDXR gene was predominantly active in the petals during the early full blooming stage. Overexpression of the OfDXR gene in Arabidopsis plants at the primary or full blooming stage led to an augmentation in the total terpenoid content. Furthermore, the promoter sequence of the OfDXR gene spanned a length of 1174 bp and contained conserved regulatory/response elements, demonstrating functional activity. These findings indicate that the OfDXR gene plays a pivotal role in terpenoid synthesis, while its promoter exhibits robust activity.
尽管 deoxylulose-5-phosphate reductoisomerase（DXR）基因及其启动子已知是植物萜类合成中关键的酶，但桂花变种四季开花的 deoxylulose-5-phosphate reductoisomerase（DXR）基因及其启动子的确切生物学功能和活性仍不清楚。本研究旨在通过 RACE-PCR 和 Hi-TAIL-PCR 技术从花瓣组织中克隆基因和启动子序列，阐明 OfDXR 基因及其启动子在桂花变种四季开花中的作用和活性。随后，利用遗传转化和组织化学染色方法分析其功能和活性。OfDXR 基因的 DNA 序列长度为 5241bp，包含 12 个外显子和 11 个内含子。OfDXR 基因的相应 cDNA 序列为 1629bp，编码 474 个氨基酸残基。表达分析表明，OfDXR 基因在初开期的花瓣中表达活跃。在拟南芥植物的初级或盛开阶段过表达 OfDXR 基因会导致总萜类化合物含量增加。此外，OfDXR 基因的启动子序列长 1174bp，包含保守的调控/反应元件，具有功能活性。这些发现表明，OfDXR 基因在萜类合成中起关键作用，而其启动子具有很强的活性。
