菌类中药野生资源日益匮乏，其发酵菌丝体成为了良好替代品。虫草素（3'-脱氧腺苷）是冬虫夏草发挥重要生物活性的关键成分，但其生物合成机制尚不明确。研究表明5'-核苷酸酶（5'-NT）在哺乳动物细胞中可介导腺苷一磷酸（AMP）去磷酸化生成腺苷，但在菌类中药中是否有相似作用尚未研究。前期冬虫夏草中国被毛孢转录组学研究发现，5'-NT基因表达上调与虫草素的积累正相关，发酵调控进一步表明5'-NT在虫草素生物合成中具有促进作用，但其功能及作用机制亟需研究。我们推测5'-NT可通过介导菌类中药3'-脱氧腺苷一磷酸（3'-dAMP）的去磷酸化合成虫草素，并在其生物合成中发挥关键作用。本研究拟采用iTRAQ和基因编辑等技术，分析和确定5'-NT的功能，明确5'-NT通过介导3'-dAMP去磷酸化调控虫草素的生物合成。本研究有望揭示菌类中药虫草素生物合成新机制，为代谢调控虫草素生物合成提供更充分的科学依据。

Wild resources of fungal traditional Chinese medicine (FTCM) is becoming scarce, and its fermentation mycelium has become a good substitute. Cordycepin (3'-deoxyadenosine) is a key component of Cordyceps sinensis that plays an important biological activity, but its biosynthesis mechanism is not clear. Studies have shown that 5'-nucleotide (5'-NT) could mediate dephosphorylation of adenosine monophosphate (AMP) into adenosine in mammalian cells, but it has not been studied whether has a similar effect in FTCM. The preliminary study which based on multi-omics sequencing results of Hirsutella sinensis found that the increase of 5'-NT gene expression was positively correlated with the accumulation of cordycepin, and the results of fermentation control were further indicated that 5'-NT plays an positive role in the biosynthesis of cordycepin, whereas its functions and mechanism of action need to be studied urgently. We proposed cordycepin was synthesized by dephosphorylation of 3'-deoxygenation adenosine monophosphate (3'-dAMP) mediated by 5'-NT in fungus medicine, and 5'-NT plays a key role in the biosynthesis of cordycepin. This study intends to adopt the methods such as iTRAQ and gene editing, and arms to analyze and identify the functions of 5'-NT, and finally confirms the effect of 5'-NT on the biosynthesis of cordycepin by mediating the dephosphorylation of 3'-dAMP in FTCM. This study is expected to reveal a new mechanism of biosynthesis of cordycepin in FTCM, and provides more scientific basis for the metabolic regulation of cordycepin biosynthesis.