目的 对银杏进行转录组测序，分析银杏生长发育不同时期类黄酮生物合成关键基因的表达。方法 以银杏幼年树和成年树不同时期叶片作为供试材料，利用Illumina HiSeq 2000进行转录组测序，对Unigene进行功能注释，分析银杏类黄酮生物合成关键基因的表达特征。结果 转录组测序共获得43 073条Unigene，其中35 179条被注释，基因差异表达（DEG）筛选得到5 117个基因。通过对类黄酮合成相关KEGG途径进行分析，筛选出50条候选基因。分析50条候选基因的表达规律，发现类黄酮合成关键基因均在银杏幼叶中高表达，但在成年树与幼年树同时期叶片之间表达差异不显著。分析与类黄酮合成关系密切的13个基因发现，其中肉桂酸4-羟化酶（C4H）、查耳酮合成酶（CHS）、花青素合成酶（ANS）、花青素还原酶（ANR）和类黄酮O-甲基转移酶（FOMT）基因的表达量较高，类黄酮3'-羟化酶（F3'H）、类黄酮3'，5'-羟化酶（F3'5'H）和黄酮醇合成酶（FLS）基因的表达量则相对较低。结论 通过转录组高通量测序，筛选分析了银杏类黄酮生物合成的关键基因及其表达特征，为提高银杏类黄酮产量提供了分子生药学理论基础。

Objective The transcriptome sequencing was used to analyze the expression of key genes of flavonoid biosynthesis in different stages of growth and development of Ginkgo biloba. Methods The leaves of young trees and adult trees of G. biloba in different periods were used as the test material. Transcriptome sequencing analysis was carried out by using Illumina HiSeq 2000, and analyses of gene functional annotation of Unigene and expression characteristics of key genes for biosynthesis of G. biloba flavonoids were also performed. Results A total of 43 073 Unigene were obtained by transcriptome sequencing, of which 35 179 were annotated and 5 117 genes were screened by differential gene expression. Fifty candidate genes were screened by analyzing KEGG pathway related to flavonoid synthesis. The expression patterns of 50 candidate genes were analyzed. It was found that the key genes of flavonoid synthesis were all highly expressed in young leaves of G. biloba, but there was no significant difference in the leaves between adult and young trees at same time. The 13 genes closely related to the synthesis of flavonoids were analyzed. Among them, the expression of C4H, CHS, ANS, ANR, and FOMT genes was high, and the expression of F3'H, F3'5'H, and FLS genes was relatively low. Conclusion Through transcriptome sequencing, we screened and analyzed the key genes of flavonoid biosynthesis of G. biloba and their expression characteristics, which provided the theoretical basis of molecular pharmacology for improving the yield of ginkgo flavonoids.

"十三五"国家重点研发计划专项（2017YFD0600701）；国家自然科学基金项目（31570682）