Abstract

Morchella is a genus of fungi with the ability to concentrate Cd both in the fruit-body and mycelium. However, the molecular mechanisms conferring resistance to Cd stress in Morchella are unknown. Here, RNA-based transcriptomic sequencing was used to identify the genes and pathways involved in Cd tolerance in Morchella spongiola. 7444 differentially expressed genes (DEGs) were identified by cultivating M. spongiola in media containing 0.15, 0.90, or 1.50 mg/L Cd²⁺. The DEGs were divided into six sub-clusters based on their global expression profiles. GO enrichment analysis indicated that numerous DEGs were associated with catalytic activity, cell cycle control, and the ribosome. KEGG enrichment analysis showed that the main pathways under Cd stress were MAPK signaling, oxidative phosphorylation, pyruvate metabolism, and propanoate metabolism. In addition, several DEGs encoding ion transporters, enzymatic/non-enzymatic antioxidants, and transcription factors were identified. Based on these results, a preliminary gene regulatory network was firstly proposed to illustrate the molecular mechanisms of Cd detoxification in M. spongiola. These results provide valuable insights into the Cd tolerance mechanism of M. spongiola and constitute a robust foundation for further studies on detoxification mechanisms in macrofungi that could potentially lead to the development of new and improved fungal bioremediation strategies.

摘要

羊肚菌是一种真菌属，能够在子实体和菌丝体中浓缩 Cd。然而，羊肚菌对镉胁迫抗性的分子机制尚不清楚。在这里，基于 RNA 的转录组测序被用于鉴定涉及羊肚菌Cd 耐受性的基因和途径。通过在含有0.15、0.90或 1.50 mg/L Cd ^{2+ 的}培养基中培养海绵状芽孢杆菌，鉴定了 7444 个差异表达基因 (DEG). DEGs 根据它们的全局表达谱分为六个子簇。GO 富集分析表明，许多 DEG 与催化活性、细胞周期控制和核糖体有关。KEGG富集分析表明，Cd胁迫下的主要途径是MAPK信号、氧化磷酸化、丙酮酸代谢和丙酸代谢。此外，还鉴定了几种编码离子转运蛋白、酶促/非酶促抗氧化剂和转录因子的 DEG。基于这些结果，首次提出了初步的基因调控网络，以阐明海绵状孢霉Cd解毒的分子机制。这些结果提供了对M. spongiola的 Cd 耐受机制的宝贵见解 并为进一步研究大型真菌的解毒机制奠定了坚实的基础，这可能会导致开发新的和改进的真菌生物修复策略。