Regulation Of Ca²⁺ Response To Heat Stress In Pleurotus Ostreatus

High temperature stress is an environmental stress often encountered in fungi during the life activities,and the response of fungi to high temperature stress is accomplished through a complex signal network.Pleurotus ostreatus has become one of the widely cultivated edible fungi due to its rich nutritional value,short growth time,high yield and quality.However,under high temperature stress,P.ostreatus often suffers from “spawn-burning” and disease infection.Calcium ion is an important second messenger,which can regulate various biological processes.Therefore,the regulation mechanism of calcium ion in P.ostreatus in response to high temperature stress was studied.After P.ostreatus(CCMSSC00389)was treated at 40 °C for 120 min,the mycelial growth was inhibited,and the intracellular calcium concentration was increased.In supplement of different calcium ion inhibitors,extracellular calcium ion chelating agent,intracellular calcium ion chelation,calmodulin inhibitor,IP3 receptor antagonist and plasma membrane calcium channel inhibitor,intracellular calcium ion concentration decreased and the mycelial growth was severely inhibited.Exogenous addition of calcium ion was found to promote mycelial growth and exogenous calcium supplementation can increase intracellular calcium ion content.The results indicate that intracellular calcium ion participates in high temperature signal transduction of P.ostreatus,and alleviates the damages of hyphae caused by high temperature.After treatment with different calcium ion inhibitors,the ROS content,trehalose content and the gene expression of heat shock proteins were detected.It was found that calcium ion regulate the ROS accumulation,trehalose production and expression of heat shock proteins under high temperature stress.