Proteomics and physiologic analysis reveal different response strategies to cadmium stress in Lentinula edodes

Lentinula edodes (L. edodes) is the second most widely cultivated edible mushroom worldwide. However, it has the ability to accumulate cadmium (Cd), which poses significant health risks. Despite its significance, the protein-level response mechanisms to Cd stress remain insufficiently understood. This study aims to investigate the differential responses of the low-Cd-accumulating strain Le4606 and the high-Cd-accumulating strain Le4625 under Cd stress by biochemical and proteomic methodologies. The results indicate that Le4625 exhibits enhanced Cd absorption, proline accumulation, and vacuolar sequestration for detoxification, with ZRC1 detected exclusively at 7 h. Conversely, Le4606 demonstrates proficiency in glutathione-mediated detoxification, thioredoxin antioxidant activity, tricarboxylic acid cycle activity, autophagy, and Cd extrusion. Overall, vacuolar sequestration and glutathione-mediated detoxification are important for the differences in Cd accumulation. The distinct response strategies offer valuable insights into the underlying mechanisms of Cd accumulation. This research establishes a theoretical foundation for the breeding of low-Cd-accumulating cultivars, benefiting human health.