目的 以箭麻（天麻Gastrodia elata的一个生长阶段）和共生天麻（白麻与蜜环菌共生的天麻）为实验材料，通过转录组测序分析初步揭示箭麻和共生天麻生长代谢特征。方法 采用Trizol Reagent（Invitrogen）提取天麻样品中的RNA，建立测序文库并利用Illumina Hiseq^TM2000进行测序，通过与基因数据库比对分析注释和发现差异表达基因。结果 箭麻与共生天麻间共获得72 244条序列，其中有26 312条得到注释。在False Discovery Rate（FDR）<0.05和|log2FC|>1筛选条件下，共有12 498条基因发生显著差异表达，其中9000条基因表达上调，3498条表达下调。京都基因和基因组百科全书（kyoto encyclopedia of genes and genomes，KEGG）功能富集分析表明，差异基因显著富集在20个代谢途径中，其中包含氮代谢，碳代谢和能量代谢等途径。差异表达基因（differentially expressed genes，DEGs）注释到蛋白相邻类的聚簇（cluster of Orthologous Groups of proteins，KOG）的25个分类中，其中差异表达基因与生长代谢过程相关过程能量的产生和转化（energy production and conversion，C）、碳水化合物转运与代谢（carbohydrate transport and metabolism，G）、次生代谢产物的合成、转运和代谢（secondary metabolites biosynthesis，transport and metabolism，Q）类别获得2218个注释结果。基于转录组数据，分析了生长代谢过程中相关基因差异表达水平，发现有利于碳、氮、能量等物质积累的谷氨酰胺合成酶（glutamine synthetase，GS）、天冬酰胺合成酶（asparagine synthetase，ASNS）、蔗糖合成酶（sucrose synthase，SuSy）、可溶性淀粉合成酶（soluble starch synthase，SSS）、ADP-葡萄糖焦磷酸化酶（ADP-glucose pyrophosphorylase，AGPase）、丙酮酸激酶（pyruvate kinase，PK）、己糖激酶（hexokinase，HK）、丙酮酸脱氢酶（pyruvate dehydrogenase，PDH），苹果酸脱氢酶（malate dehydrogenase，MDH），异柠檬酸脱氢酶（isocitrate dehydrogenase，IDH）基因呈上调表达，除分解ATP的ATP酶（adenosine-triphosphatase，ATPase）上调外，分解氮、碳物质的谷氨酸脱氢酶（glutamate dehydrogenase，GDH）、精氨酸酶（arginase，Argase）和淀粉酶（amylase，AMS）基因呈下调表达。qRT-PCR分析结果表明这些基因表达水平与转录组表达情况基本一致。相比较于箭麻，共生天麻生长代谢中物质积累比较旺盛。结论 共生天麻通过消解侵入的蜜环菌合成有机营养物质和能量，有利于其从蜜环菌和周围环境吸收营养物质供箭麻生长需要，为进一步研究天麻不同发育阶段代谢特征奠定基础，并为天麻栽培提供理论指导。

Objective Using mature tuber of Gastrodia elata (A growth stage of G. elata) and symbiotic G. elata (immature tuber of G. elata symbiosis with Armillaria mella) as experimental materials, their characteristics of growth and metabolism were preliminarily revealed by transcriptome sequencing analysis. Methods The RNA of G. elata sample was extracted using Trizol Reagent (Invitrogen). The sequencing library was constructed and sequenced using Illumina Hiseq^TM2000 and the differentially expressed genes were analyzed by comparison with the gene database. Results A total of 72244 sequences were obtained from the symbiotic G. elata and the mature tuber of G. elata, in which 26 312 were annotated. Under the screening conditions of FDR<0.05 and|log2FC|>1, a total of 12498 genes were significantly differentially expressed, in which 9000 genes were up-regulated and 3498 genes were down-regulated. KEGG functional enrichment analysis indicated that differential genes were involved in nitrogen metabolism, carbon metabolism and energy metabolism. DEGs was annotated in 25 categories of KOG, among which 2218 annotation results were obtained in categories C,G and Q related to differentially expressed genes in growth and metabolism. Based on transcriptome data, the differential expression levels of related genes in the process of growth and metabolism were analyzed. We found GS, ASNS, SuSy, SSS, AGPase, PK, HK, PDH, MDH, IDH, which are beneficial to the accumulation of carbon, nitrogen, energy and other substance were up-regulated. In addition to the up-regulation of ATPase in the decomposition of ATP, Argase, GDH, AMS in the decomposition of nitrogen and carbon were down-regulated. qRT-PCR analysis showed that the expression levels of these genes were basically consistent with the transcriptome expression. Compared with the mature tuber of G. elata, the material accumulation in the symbiotic G. elata was more vigorous. Conclusion These results indicated that the symbiotic G. elata synthesizes organic nutrients and energy through the digestion of the invaded A. mella, which is conducive to the absorption of nutrients from A. mella and the surrounding environment for the growth of mature tuber. It lays a foundation for further study of the metabolic characteristics of different developmental stages of G. elata and provides theoretical guidance for G. elata cultivation.

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国家自然科学基金资助项目（31760349）；国家自然科学基金资助项目（31560351）