Laboratory of Modern Biotechnology, School of Forestry and Landscape Architecture, Anhui Agricultural University, Hefei, 230036, China.
National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei, 230036, China.
BMC Plant Biol. 2021 Oct 6;21(1):447. doi: 10.1186/s12870-021-03224-x.
Panax notoginseng (Burk.) F. H. Chen (P. notoginseng) is a medicinal plant. Cytochrome P450 (CYP450) monooxygenase superfamily is involved in the synthesis of a variety of plant hormones. Studies have shown that CYP450 is involved in the synthesis of saponins, which are the main medicinal component of P. notoginseng. To date, the P. notoginseng CYP450 family has not been systematically studied, and its gene functions remain unclear.
In this study, a total of 188 PnCYP genes were identified, these genes were divided into 41 subfamilies and clustered into 9 clans. Moreover, we identified 40 paralogous pairs, of which only two had Ka/Ks ratio greater than 1, demonstrating that most PnCYPs underwent purification selection during evolution. In chromosome mapping and gene replication analysis, 8 tandem duplication and 11 segmental duplication events demonstrated that PnCYP genes were continuously replicating during their evolution. Gene ontology (GO) analysis annotated the functions of 188 PnCYPs into 21 functional subclasses, suggesting the functional diversity of these gene families. Functional divergence analyzed the members of the three primitive branches of CYP51, CYP74 and CYP97 at the amino acid level, and found some critical amino acid sites. The expression pattern of PnCYP450 related to nitrogen treatment was studied using transcriptome sequencing data, 10 genes were significantly up-regulated and 37 genes were significantly down-regulated. Combined with transcriptome sequencing analysis, five potential functional genes were screened. Quantitative real-time PCR (qRT-PCR) indicated that these five genes were responded to methyl jasmonate (MEJA) and abscisic acid (ABA) treatment.
These results provide a valuable basis for comprehending the classification and biological functions of PnCYPs, and offer clues to study their biological functions in response to nitrogen treatment.
三七（Panax notoginseng (Burk.) F. H. Chen）是一种药用植物。细胞色素 P450（CYP450）单加氧酶超家族参与多种植物激素的合成。研究表明，CYP450 参与了皂苷的合成，皂苷是三七的主要药用成分。迄今为止，三七 CYP450 家族尚未得到系统研究，其基因功能尚不清楚。
本研究共鉴定出 188 个 PnCYP 基因，这些基因分为 41 个亚家族，并聚类为 9 个族。此外，我们鉴定出 40 个旁系同源对，其中只有两个具有 Ka/Ks 比值大于 1，表明大多数 PnCYPs 在进化过程中经历了纯化选择。在染色体定位和基因复制分析中，发现 8 个串联重复和 11 个片段重复事件，表明 PnCYP 基因在进化过程中不断复制。基因本体（GO）分析将 188 个 PnCYP 的功能注释为 21 个功能亚类，表明这些基因家族具有功能多样性。功能分化分析了 CYP51、CYP74 和 CYP97 三个原始分支的成员在氨基酸水平上的功能，发现了一些关键的氨基酸位点。使用转录组测序数据研究了与氮处理相关的 PnCYP450 的表达模式，发现 10 个基因显著上调，37 个基因显著下调。结合转录组测序分析，筛选出 5 个潜在的功能基因。定量实时 PCR（qRT-PCR）表明，这 5 个基因对茉莉酸甲酯（MEJA）和脱落酸（ABA）处理有反应。
这些结果为理解 PnCYP 的分类和生物学功能提供了有价值的依据，并为研究其对氮处理的生物学功能提供了线索。
