Li Hui, Yao Sen, Xia Weiwei, Ma Xinbin, Shi Lei, Ju Huimin, Li Ziyan, Zhong Yingli, Xie Baogui, Tao Yongxin
Institute of Cash Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang, Hebei, China.
College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
Front Microbiol. 2023 Sep 20;14:1195709. doi: 10.3389/fmicb.2023.1195709. eCollection 2023.
, a typical agaric fungus, is a widely cultivated and consumed edible mushroom. Elongation of its stipe (as the main edible part) is closely related to its yield and commercial traits; however, the endogenous hormones during stipe elongation and their regulatory mechanisms are not well understood. Gibberellin (GA) plays an important role in the regulation of plant growth, but little has been reported in macro fungi. In this study, we first treated stipes in the young stage with PBZ (an inhibitor of GA) and found that PBZ significantly inhibited elongation of the stipe. Then, we performed GA-targeted metabolome and transcriptome analyses of the stipe at both the young and elongation stages. A total of 13 types of GAs were detected in ; the contents of ten of them, namely, GA3, GA4, GA8, GA14, GA19, GA20, GA24, GA34, GA44, and GA53, were significantly decreased, and the contents of three (GA5, GA9, and GA29) were significantly increased during stipe elongation. Transcriptome analysis showed that the genes in the terpenoid backbone biosynthesis pathway showed varying expression patterns: , and were significantly upregulated, while had no significant difference in transcript level during stipe elongation. In total, 37 genes were annotated to be involved in GA biosynthesis; eight of them were upregulated, twelve were downregulated, and the rest were not differentially expressed. In addition, four types of differentially expressed genes involved in stipe elongation were identified, including six signal transduction genes, five cell cycle-controlling genes, twelve cell wall-related enzymes and six transcription factors. The results identified the types and content of GAs and the expression patterns of their synthesis pathways during elongation in and revealed the molecular mechanisms by which GAs may affect the synthesis of cell wall components and the cell cycle of the stipe through the downstream action of cell wall-related enzymes, transcription factors, signal transduction and cell cycle control, thus regulating stipe elongation. This study is helpful for understanding the roles of GAs in stipe development in mushrooms and lays the foundation for the rational regulation of stipe length in agaric mushrooms during production.
作为一种典型的伞菌，是一种广泛种植和食用的食用菌。其菌柄（作为主要可食用部分）的伸长与其产量和商业性状密切相关；然而，菌柄伸长过程中的内源激素及其调控机制尚不清楚。赤霉素（GA）在植物生长调节中起重要作用，但在大型真菌中的报道较少。在本研究中，我们首先用PBZ（一种GA抑制剂）处理幼嫩阶段的菌柄，发现PBZ显著抑制了菌柄的伸长。然后，我们对幼嫩阶段和伸长阶段的菌柄进行了GA靶向代谢组和转录组分析。在中总共检测到13种GA；其中10种，即GA3、GA4、GA8、GA14、GA19、GA20、GA24、GA34、GA44和GA53的含量显著降低，而三种（GA5、GA9和GA29）的含量在菌柄伸长过程中显著增加。转录组分析表明，萜类骨架生物合成途径中的基因表现出不同的表达模式：、和显著上调，而在菌柄伸长过程中转录水平无显著差异。总共注释了37个参与GA生物合成的基因；其中8个上调，12个下调，其余无差异表达。此外，还鉴定了4种参与菌柄伸长的差异表达基因，包括6个信号转导基因、5个细胞周期控制基因、12个细胞壁相关酶和6个转录因子。结果确定了中菌柄伸长过程中GA的类型和含量及其合成途径的表达模式，并揭示了GA可能通过细胞壁相关酶、转录因子、信号转导和细胞周期控制的下游作用影响细胞壁成分合成和菌柄细胞周期，从而调节菌柄伸长的分子机制。本研究有助于理解GA在蘑菇菌柄发育中的作用，为生产过程中合理调控木耳菌柄长度奠定基础。
