Feng Lidan, Wang Lujuan, Lei Yuanxi, Li Jie, Zhao Fengyun
College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China.
College of Forestry, Gansu Agricultural University, Lanzhou 730070, China.
J Fungi (Basel). 2024 Dec 25;11(1):7. doi: 10.3390/jof11010007.
Periodic mycelial subculture is a method commonly used for the storage of edible mushrooms, but excessive subculturing can lead to the degeneration of strains. In this study, the strain V971(M0) was successively subcultured on PDA medium every 4 days, and one generation of strains was preserved every 4 months. Thus, five generations of subcultured strains (M1-M5) were obtained after 20 months of mycelial subculturing, their production traits were determined, and transcriptomic analysis was performed using RNA-seq; the differentially expressed genes were verified via RT-qPCR. The results showed that as the number of subcultures increased, the diameter of the mycelium and biological efficiency gradually decreased; in addition, the time in which the primordium formed increased and the production cycle was lengthened, while strains M4 and M5 lacked the ability to produce fruiting bodies. There were 245 differentially expressed genes between the M1-M5 and M0 strains, while the highest number of differentially expressed genes was between M3 and M0, at 1439; the smallest number of differentially expressed genes was between M2 and M0, at 959. GO enrichment analysis showed that the differentially expressed genes were mainly enriched in metabolic processes, organelle components, and catalytic activities. KEGG enrichment analysis showed that the differentially expressed genes were mainly enriched in metabolic pathways. The further annotation of differentially expressed genes showed that 39, 24, and 24 differentially expressed genes were related to substrate degradation, amino acid synthesis and metabolism, and reactive oxygen species metabolism, respectively. The downregulation of the related differentially expressed genes would lead to the excessive accumulation of reactive oxygen species, inhibit nutrient absorption and energy acquisition, and lead to the degradation of . These findings could form a theoretical basis for the degeneration mechanism of and also provide a basis for the molecular function study of the genes related to strain degradation.
定期进行菌丝体继代培养是一种常用于保存食用菌的方法，但过度继代培养会导致菌株退化。在本研究中，V971(M0)菌株每4天在PDA培养基上连续继代培养一次，每4个月保存一代菌株。因此，经过20个月的菌丝体继代培养后获得了五代继代培养菌株(M1-M5)，测定了它们的生产性状，并使用RNA-seq进行转录组分析；通过RT-qPCR验证差异表达基因。结果表明，随着继代培养次数的增加，菌丝体直径和生物学效率逐渐降低；此外，原基形成时间增加，生产周期延长，而M4和M5菌株缺乏产生子实体的能力。M1-M5与M0菌株之间有245个差异表达基因，其中差异表达基因数量最多的是M3与M0之间，为1439个；差异表达基因数量最少的是M2与M0之间，为959个。GO富集分析表明，差异表达基因主要富集在代谢过程、细胞器成分和催化活性中。KEGG富集分析表明，差异表达基因主要富集在代谢途径中。差异表达基因的进一步注释表明，分别有39、24和24个差异表达基因与底物降解、氨基酸合成与代谢以及活性氧代谢相关。相关差异表达基因的下调会导致活性氧的过度积累，抑制营养吸收和能量获取，并导致……的退化。这些发现可为……的退化机制形成理论基础，也为菌株退化相关基因的分子功能研究提供依据。
