目的 通过分析八角Illicium verum不同组织部位的基因转录水平差异，挖掘八角果实中木脂素生物合成途径相关酶基因，为八角木脂素生物合成途径关键酶基因研究提供参考。方法 利用PacBio和Illumina测序平台对八角的茎、嫩叶、老叶、花及果实进行全长转录组测序与比较转录组学分析，通过WGCNA分析挖掘具有组织特异表达的木脂素生物合成途径关键酶基因，利用qRT-PCR对候选基因的表达情况进行验证。结果 经过纠错去除冗余后共获得32 996条高质量转录本，平均长度2 033 bp，N₅₀长度2 343 bp，其中31 248条在公共数据库获得注释。共鉴定到39条参与木脂素生物合成的转录本，涉及10个关键酶基因，其中在八角果实中高表达的有14条转录本，涉及6个酶基因。八角果实中与其他组织相比，差异表达的基因富集在苯丙烷代谢途径中。通过WGCNA分析鉴定到15个共表达模块，在果实特异表达模块（MEred）中挖掘到木脂素合成关键酶基因4CL、CCR共3条转录本。候选基因PAL（transcript11647），C4H（transcript26532），4CL（transcript12186），CCR（transcript27851）和CAD（transcript27743）在不同组织中的表达情况与转录组数据一致。结论 为八角分子生药学研究提供了可靠的转录组数据库，也为八角果实中木脂素生物合成途径关键酶基因研究提供了研究基础。

Objective The differences in the gene expression of Illicium verum in different tissues and enzyme genes of lignan biosynthesis pathway in fruits of I. verum were analyzed to provide a basis for the study of key enzyme genes in the biosynthetic pathway of lignin in I. verum. Methods PacBio and Illumina sequencing platforms were used to perform full-length transcriptome sequencing of stems, tender leaves, mature leaves, flowers and fruits of I. verum, and comparative transcriptome analysis of different tissues were carried out. Key enzyme genes of lignan biosynthesis pathway with tissue-specific expression were excavated by weighted gene co-expression network analysis (WGCNA), and the expression of candidate genes was verified by qRT-PCR. Results A total of 32 996 high-quality transcripts were obtained after error correction and redundancy removal, with an average length of 2 033 bp and an N₅₀ length of 2 343 bp, of which 31 248 were annotated in the public database. A total of 39 transcripts involved in lignan biosynthesis were identified, involving 10 key enzyme genes. Among them, 14 transcripts were highly expressed in the fruits of I. verum, involving six enzyme genes. Compared with other tissues, the differentially expressed genes in fruits of I. verum were enriched in the phenylpropanoid metabolic pathway. A total of 15 co-expression modules were identified by WGCNA, among which three transcripts of the key enzyme gene of lignan biosynthesis pathway (4CL and CCR) were excavated in the fruit-specific expression module (MEred). The expression of candidate genes PAL (transcript11647), C4H (transcript26532), 4CL (transcript12186), CCR (transcript27851) and CAD (transcript27743) in different tissues was consistent with the transcriptome data.Conclusion Our study provides a reliable transcriptome database for the study of molecular pharmacognosy of I. verum, and also provides a research foundation for the investigation of key enzyme genes of lignan biosynthesis in I. verum fruits.

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广西科技重大专项项目（桂科AA22096029）;广西创新驱动发展专项资金项目（桂科AA23023035）;广西中医药大学-柳药集团青年科技创新能力提升计划专项项目（GL-2023-01）