Yao Wei-Lin, Pan Jie, Niu Teng-Fei, Yang Xiao-Lin, Zhao Shu-Juan, Wang Zheng-Tao, Wang Ru-Feng
Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China the SATCM Key Laboratory for New Resources & Quality Evaluation of Chinese Medicine, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China.
Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China the SATCM Key Laboratory for New Resources & Quality Evaluation of Chinese Medicine, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China Shanghai R&D Center for Standardization of Traditional Chinese Medicines Shanghai 201203, China the MOE Key Laboratory for Standardization of Chinese Medicines, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China.
Zhongguo Zhong Yao Za Zhi. 2022 Sep;47(17):4593-4599. doi: 10.19540/j.cnki.cjcmm.20220514.102.
Dipsaci Radix is one of the commonly used Chinese medicinal materials in China, with a long history. It has the medicinal activities of nourishing liver and kidney, recovering from broken sinews, and treating bone fracture. Triterpenoid saponins are the main functional ingredients of Dipsacus asper. β-Amyrin synthases(β-AS) as a superfamily of oxidosqualene cyclases(OSCs) can catalyze the construction of the skeleton structure of oleanane-type triterpenoid saponins. There are only a few studies about the β-AS in D. asper, and the catalytic mechanism of this enzyme remains to be explored. To enrich the information of β-AS, according to the transcriptome sequencing results, we cloned DaWβ-AS gene from D. asper into a specific vector for heterologous expression in Escherichia coli. In the meantime, real-time PCR was performed to analyze the relative expression of DaWβ-AS in four different tissues of D. asper. The results of RT-qPCR showed DaWβ-AS had the highest expression level in leaves. Bioinformatics results indicated that DaWβ-AS had a conserved domain of PLN03012 superfamily, belonging to the cl31551 superfamily. There was no transmembrane domain or signal peptide in DaWβ-AS. This study provides a scientific basis for revealing the biological pathways of triterpenoid saponins in D. asper, which will facilitate the biosynthesis of the associated saponins and afford reference for the cultivation and development of high-quality resources of D. asper.
续断是我国常用中药材之一，历史悠久。它具有滋补肝肾、续筋接骨、治疗骨折的药用活性。三萜皂苷是川续断的主要功能成分。β-香树脂醇合酶（β-AS）作为氧化鲨烯环化酶（OSCs）超家族的一员，可催化齐墩果烷型三萜皂苷骨架结构的构建。关于川续断中β-AS的研究较少，该酶的催化机制仍有待探索。为丰富β-AS的信息，根据转录组测序结果，我们将川续断中的DaWβ-AS基因克隆到特定载体中，在大肠杆菌中进行异源表达。同时，进行实时荧光定量PCR分析DaWβ-AS在川续断四个不同组织中的相对表达。RT-qPCR结果显示DaWβ-AS在叶片中表达水平最高。生物信息学结果表明，DaWβ-AS具有PLN03012超家族的保守结构域，属于cl31551超家族。DaWβ-AS中没有跨膜结构域或信号肽。本研究为揭示川续断中三萜皂苷的生物合成途径提供了科学依据，有助于相关皂苷的生物合成，并为川续断优质资源的培育和开发提供参考。
