目的 基于茉莉酸甲酯（methyl jasmonate，MeJA）处理下的天麻Gastrodia elata比较转录组测序，筛选与天麻素及巴利森苷E化合物生物合成相关的关键酶基因。方法 以箭麻和共生白头麻为实验材料，采用不同浓度（100～500 μmol/L）MeJA喷施处理不同时间（0～72 h），采用HPLC对天麻素和巴利森苷E的含量变化进行测定，对最佳MeJA处理条件下的样品进行转录组和代谢组联合分析，挖掘巴利森苷E生物合成途径的关键基因。结果 在300 μmol/L MeJA处理48 h后，2个目标化合物含量均显著提升，其中巴利森苷E由初始的0.21 mg/g显著增至0.61 mg/g，提升2.90倍，故选定该处理条件进行转录组分析。测序共获得432.79 Gb Clean Data，检测到18 886个表达基因，含2 389个新基因。差异分析共筛选出5 704个差异基因，其中2 635个上调、3 069个下调。KEGG富集显示差异基因表达主要集中于苯丙素生物合成、植物信号转导等次生代谢相关通路。通过表达模式与化合物积累关联分析及同源比对，筛选出可能参与巴利森苷E生物合成途径中关键基因6条，糖基转移酶基因（GeUGT）、柠檬酰辅酶A合成酶基因（GeCCS）和酰基转移酶基因（GeBAHD）各2条。结论 证实MeJA能有效调控天麻次生代谢，并筛选出与天麻素及巴利森苷E生物合成可能相关的候选基因（GeUGTs、GeCCSs、GeBAHDs），为完整解析这些关键活性成分的生物合成途径奠定了分子基础。

Objective This study aimed to screen key enzyme genes associated with the biosynthesis of gastrodin and parishin E in Gastrodia elata. Through comparative transcriptome sequencing following methyl jasmonate (MeJA) treatment. Methods Using both the corm (MTE and the symbiotic tuber (IMTC) as experimental materials, different concentrations (100—500 μmol/L) of MeJA were sprayed for varying durations (0—72 h). The content changes of gastrodin and parishins E were determined by HPLC. Transcriptomic and metabolomic analyses were performed on samples treated under the optimal MeJA conditions to mine key genes in the parishin E biosynthetic pathway. Results After 48 h of treatment with 300 μmol/L MeJA, the contents of all six target compounds were significantly increased. Specifically, the content of parishin E increased from 0.21 mg/g to 0.61 mg/g, representing an approximately 2.90-fold enhancement. Transcriptome sequencing generated 432.79 Gb of Clean Data and identified 18 886 expressed genes, including 2 389 novel genes. Differential expression analysis revealed 5 704 differentially expressed genes, with 2 635 up-regulated and 3 069 down-regulated. KEGG enrichment analysis showed significant enrichment in phenylpropanoid biosynthesis, plant signal transduction, and other secondary metabolism-related pathways. Through integrated analysis of expression patterns and compound accumulation trends, along with homology comparison, we identified two glycosyltransferase genes GeUGT, two citrate-CoA synthetase genes GeCCS, and two acyltransferase genes GeBAHD potentially involved in parishin E biosynthesis. Conclusion This study demonstrates that MeJA effectively regulates secondary metabolism in G. elata and identifies candidate genes (GeUGTs, GeCCSs, GeBAHDs) potentially associated with the biosynthesis of gastrodin and parishin E, providing a molecular foundation for elucidating the complete biosynthetic pathways of these key active compounds.

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云南省科技厅基础研究专项（202201AT070274）