食用菌学报2025，Vol.32Issue(3)：13-27,15.DOI:10.16488/j.cnki.1005-9873.2025.03.002
基于转录组分析金针菇子实体发育过程中GABA生物合成机制
Transcriptome Analysis of Mechanism of Gamma-Aminobutyric Acid Biosynthesis in Flammulina filiformis During Fruiting Body Development
摘要
Abstract
Gamma-aminobutyric acid(GABA),ubiquitously exists in edible fungi,is a non-protein natural amino acid with important physiological functions.The content of GABA is high in Flammulina filiformis.To understand the biosynthetic mechanism of GABA in F.filiformis,samples of F.filiformis fruiting bodies at 15 d,21 d and 25 d after scratching were analyzed for transcriptome data,with 15-21 d defined as elongation stage and 21-25 d defined as mature stage.Samples of different collection time were also measured for contents of GABA and its precursors so as to identify genes related to GABA biosynthesis.RT-qPCR and addition of key substances in the biosynthesis pathway were used to verify the identified genes.The results showed that GABA and its synthetic precursors,glutamate and ornithine,initially increased and then decreased as the fruiting bodies elongate and mature,whereas the content of arginine kept increasing.Compared with the samples of 15 d,there were 869 and 641 differentially expressed genes(DEGs)at the elongation and mature stages,respectively.GO functional enrichment analysis showed that the DEGs were mainly enriched in secondary units such as putrescine catabolism,polyamine catabolism,ornithine biosynthesis,and glutamate metabolism.KEGG metabolic pathway analysis showed that the DEGs were mainly enriched in metabolism of various amino acids and biosynthesis of steroids and folate.By RT-qPCR validation and functional prediction analysis,scaffold1.g1430,scaffold1.g390,scaffold6.g197,scaffold9.g519,and scaffold11.g88 were potential important genes related to GABA biosynthesis in F.filiformis,and they were also involved in the synthesis of various precursors in the GABA shunt and polyamine degradation pathway.The addition of 0.5 g·L-1 L-glutamic acid and 0.2 g·L-1 CaCl2 to liquid medium increased GABA content in mycelia of F.filiformis,suggesting that the GABA shunt may be involved in GABA biosynthesis in F.filiformis.These findings provided a reference for elucidating the GABA metabolic pathway in F.filiformis.关键词
食用菌/γ-氨基丁酸/GABA支路/多胺降解/代谢通路Key words
Edible fungi/γ-aminobutyric acid(GABA)/GABA shunt pathway/polyamine degradation/metabolic pathway引用本文复制引用
李文云,卢雪伟,邵悠然,王瑞娟,尚晓冬,冯占,李贺文,吴莹莹..基于转录组分析金针菇子实体发育过程中GABA生物合成机制[J].食用菌学报,2025,32(3):13-27,15.基金项目
上海市科技兴农重点攻关项目[沪农科创字(2022)第02-08-00-12-F01137号] （2022）
