Mnsod1 promotes the development of Pleurotus ostreatus and enhances the tolerance of mycelia to heat stress

Abstract

Background Superoxide dismutases (SODs, EC 1.15.1.1) are defense proteins that can be used as sweepers to clear reactive oxygen species (ROS). They have been widely studied in the plant. Intensive research demonstrates that SOD plays an essential role in plants. However, in Pleurotus ostreatus, the function and regulatory pathway of SOD in the growth and development and the abiotic stress response have not been clear. Results In this study, three MnSOD-encoding genes of the P. ostreatus CCMSSC00389 strain were cloned and identified. Mnsod1, Mnsod2, and Mnsod3 were interrupted by 3, 7, and 2 introns, and encoded proteins of 204, 220, and 344 amino acids, respectively. By comparing the relative expression of three MnSOD-encoding genes in mycelia, the results showed that the gene with the highest primary expression was Mnsod1. Subsequently, the function of P. ostreatus Mnsod1 was explored by overexpression (OE) and RNA interference (RNAi). The results showed that during the growth and development of P. ostreatus, MnSOD1 protein increased gradually from mycelia to the fruiting body, but decreased in spores. The change of Mnsod1 transcription level was not consistent with the changing trend of MnSOD1 protein. Further studies showed that during primordia formation, the expression of Mnsod1 gradually increased, reaching a peak at 48 h, and the transcription level was 2.05-folds compared to control. H2O2 content progressively accumulated during the formation of primordia, and its change trend was similar to that of Mnsod1 transcription. OE-Mnsod1-1 and OE-Mnsod1-21 strains accelerated the formation of primordia. The results suggested that Mnsod1 may participate in the formation rate of P. ostreatus primordium by regulating the signal molecule H2O2. In addition, OE-Mnsod1-1 and OE-Mnsod1-21 strains shortened the mycelial recovery time after heat stress and improved the tolerance of the strains to 2.5 mM and 5 mM H2O2, which showed that Mnsod1 was involved in the response of P. ostreatus mycelium to heat stress. Conclusions This study indicates that Mnsod1 plays an active role in the formation of P. ostreatus primordia and the response to abiotic stress.

Nitric Oxide Negatively Regulates the Rapid Formation of Pleurotus ostreatus Primordia by Inhibiting the Mitochondrial aco Gene

“…Previous studies have shown that H 2 O 2 is abundant at the edge of colonies on PDA plates. It is speculated that the presence of H 2 O 2 may regulate the elongation of apical mycelia [ 38 ]. The results of this study showed that H 2 O 2 accumulated gradually during the transformation from mycelia to primordia in P. ostreatus ( Figure 6 A,B).…”

Function of Transcription Factors PoMYB12, PoMYB15, and PoMYB20 in Heat Stress and Growth of Pleurotus ostreatus

“…The OE-aox strain can actively respond to 32 • C heat stress in mycelium [22]. After being subjected to heat stress, strain OE-Mnsod1 has a faster mycelial recovery rate than the WT strain and participates in the mycelial heat stress reaction of P. ostreatus [27]. Therefore, determining whether pal1, pal2, aox, and Mnsod1 are regulated by PoMYB12, PoMYB15, or PoMYB20 and their involvement in the heat stress regulatory pathway warrants further investigation.…”

“…Using the research method of Ludan Hou [27], the amplification of the hygromycin (Hyg) gene in P. ostreatus, transformed with the OE-PoMYB12 plasmid, was conducted (Figure S3a). Subsequently, the relative expression level of the PoMYB12 in the transformed strains was detected.…”

SIRT2-mediated deacetylation of Glutathione transferase alleviates oxidative damage and increases heat tolerance of Pleurotus ostreatus

“…Various substances, such as trehalose, salicylic acid (SA), and nitric oxide (NO), can enhance the ability of P. ostreatus to survive under HS by helping them maintain redox and metabolic homeostasis (Lei et al, 2019;Hou et al, 2020;Hu et al, 2022). Several metabolic enzymes, such as MnSOD1, PAL, aconitase, and alternative oxidase, can also help P. ostreatus cope with HS (Hou et al, 2019;Hou et al, 2020;Hou et al, 2021;Hou et al, 2022). In another study, we found that metabolism is rearranged under HS in P. ostreatus.…”