Xu Lili, Guo Lizhong, Yu Hao
Shandong Provincial Key Laboratory of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao, China.
Front Microbiol. 2021 Jan 5;11:541967. doi: 10.3389/fmicb.2020.541967. eCollection 2020.
Heat stress is an important adverse environmental stress that influences the growth and development of (white var.). However, the molecular basis of heat stress response in remains poorly understood. In this study, label-free comparative proteomic technique was applied to investigate global protein expression profile of mycelia under heat stress. Confocal laser scanning microscope observation revealed that mycelia underwent autolysis and apoptosis under heat stress. Autolysis was mediated by upregulating the expression of cell wall degradation enzymes and inhibiting cell wall synthesis enzymes, and apoptosis might be induced by ROS and activation of caspases. TBARS analysis indicated that ROS was accumulated in mycelia under heat stress. induced antioxidant defense system by upregulating the expression of catalases, superoxide dismutases and peroxidases to prevent oxidative damage. MAPK cascade was found to be involved in heat stress signal transduction. The stress signal induced a ubiquitous defense response: inducible expression of different kinds of heat shock proteins. Trehalose synthesis enzymes were also upregulated, suggesting the accumulation of stress protector trehalose under heat stress. Besides, upregulated proteasome was identified, which could prevented the accumulation of non-functional misfolding proteins. To satisfy ATP depletion in heat response cellular processes, such as ROS scavenging, and protein folding and synthesis, enzymes involved in energy production (carbon metabolism and ATP synthesis) system were upregulated under heat stress. Taken together, these findings improve our understanding of the molecular mechanisms underlying the response of heat stress in .
热胁迫是一种重要的不良环境胁迫，会影响（白色变种）的生长和发育。然而，（该物种）热胁迫响应的分子基础仍知之甚少。在本研究中，采用无标记比较蛋白质组学技术来研究热胁迫下（该物种）菌丝体的整体蛋白质表达谱。共聚焦激光扫描显微镜观察显示，热胁迫下菌丝体会发生自溶和凋亡。自溶是通过上调细胞壁降解酶的表达和抑制细胞壁合成酶来介导的，而凋亡可能是由活性氧（ROS）和半胱天冬酶的激活所诱导。硫代巴比妥酸反应物（TBARS）分析表明，热胁迫下（该物种）菌丝体中ROS会积累。（该物种）通过上调过氧化氢酶、超氧化物歧化酶和过氧化物酶的表达来诱导抗氧化防御系统，以防止氧化损伤。发现丝裂原活化蛋白激酶（MAPK）级联参与热胁迫信号转导。应激信号诱导了一种普遍的防御反应：不同种类热休克蛋白的诱导表达。海藻糖合成酶也被上调，这表明热胁迫下应激保护剂海藻糖会积累。此外，还鉴定出蛋白酶体上调，其可以防止无功能错误折叠蛋白的积累。为了满足热响应细胞过程中ATP的消耗，如ROS清除以及蛋白质折叠和合成，参与能量产生（碳代谢和ATP合成）系统的酶在热胁迫下被上调。综上所述，这些发现增进了我们对（该物种）热胁迫响应潜在分子机制的理解。
