Nitric Oxide Improves the Tolerance of Pleurotus ostreatus to Heat Stress by Inhibiting Mitochondrial Aconitase

• Published in: Applied and environmental microbiology 2020-02, Vol.86 (5)
• Main Authors: Hou, Ludan, Zhao, Mengran, Huang, Chenyang, Wu, Xiangli, Zhang, Jinxia
• Format: Article
• Language: English
• Subjects: Alternative oxidase; Citric acid; Cultivation; Damage; Gene expression; Genetics and Molecular Biology; Heat stress; Heat tolerance; High temperature; Hydrogen peroxide; Mitochondria; Mycelia; Nitric oxide; Pleurotus ostreatus; Proteins; Trehalose
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/AEM.02303-19

is widely cultivated in China. However, its cultivation is strongly affected by seasonal temperature changes, especially the high temperatures of summer. Nitric oxide (NO) was previously reported to alleviate oxidative damage to mycelia by regulating trehalose. In this study, we found that NO alleviated oxidative damage to mycelia by inhibiting the protein and gene expression of aconitase (ACO), and additional studies found that the overexpression and interference of could affect the content of citric acid (CA). Furthermore, the addition of exogenous CA can induce alternative oxidase ( ) gene expression under heat stress, reduce the content of H O in mycelium, and consequently protect the mycelia under heat stress. An additional analysis focused on the function of the gene in the heat stress response of mycelia. The results show that the colony diameter of the overexpression (OE- ) strains was significantly larger than that of the wild-type (WT) strain under heat stress (32°C). In addition, the mycelia of OE- strains showed significantly enhanced tolerance to H O In conclusion, this study demonstrates that NO can affect CA accumulation by regulating gene and ACO protein expression and that CA can induce gene expression and thereby be a response to heat stress. Heat stress is one of the abiotic stresses that affect the growth and development of edible fungi. Our previous study found that exogenous NO had a protective effect on mycelia under heat stress. However, its regulatory mechanism had not been elucidated. In this study, we found that NO altered the respiratory pathway of mycelia under heat stress by regulating The results have enhanced our understanding of NO signaling pathways in .