Pyruvate Accumulation Is the First Line of Cell Defense against Heat Stress in a Fungus.
Pyruvate Accumulation Is the First Line of Cell Defense against Heat Stress in a Fungus.
复制标题
丙酮酸积累是真菌细胞抵御热应激的第一道防线
DOI：
10.1128/mbio.01284-17
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发表时间：
2017-09-05
期刊：
影响因子：
6.4
通讯作者：
Fang W
中科院分区：
文献类型：
--
作者：
Zhang X;St Leger RJ;Fang W
摘要耐热性是真菌在许多生境中生存的关键，但我们对生物体如何适应热胁迫的机制的理解仍然是不完整的。使用绿僵菌robertsii，一个新兴的模式生物评估进化过程中，我们报告说，丙酮酸是在先锋分子的热诱导活性氧（ROS）。我们发现，以及诱导快速爆发的活性氧产生，热应激也下调丙酮酸消耗的基因。积累的丙酮酸是几种M中作用最快的。robertsii ROS清除剂，有效降低蛋白质羰基化，稳定线粒体膜电位，促进真菌生长。由磷酸盐-ROS反应产生的乙酸盐本身引起酸胁迫，对酸胁迫的耐受性由Hog 1丝裂原活化蛋白激酶调节。热应激也诱导丙酮酸积累在其他几种真菌，表明丙酮酸清除热诱导的活性氧是普遍的。重要性热对大多数生物体来说是一个危险的挑战，因为它使蛋白质变性，并诱导产生ROS，使蛋白质，脂质膜和DNA变性。生物体如何应对这种压力尚未完全了解。使用实验上易处理的昆虫病原体罗伯茨绿僵菌作为模式生物，我们第一次表明，热应激诱导丙酮酸的生产，这是第一道防线对热诱导的活性氧的功能。热应激也诱导其他真菌中丙酮酸的快速积累，表明丙酮酸是一种常见但未被重视的抗应激防御。对于大多数生物体来说，热是一个危险的挑战，因为它使蛋白质变性并诱导产生ROS，使蛋白质，脂质膜和DNA变性。生物体如何应对这种压力尚未完全了解。使用实验上易处理的昆虫病原体罗伯茨绿僵菌作为模式生物，我们第一次表明，热应激诱导丙酮酸的生产，这是第一道防线对热诱导的活性氧的功能。热应激也诱导其他真菌中丙酮酸的快速积累，表明丙酮酸是一种常见但未被重视的抗应激防御。
ABSTRACT Heat tolerance is well known to be key to fungal survival in many habitats, but our mechanistic understanding of how organisms adapt to heat stress is still incomplete. Using Metarhizium robertsii, an emerging model organism for assessing evolutionary processes, we report that pyruvate is in the vanguard of molecules that scavenge heat-induced reactive oxygen species (ROS). We show that, as well as inducing a rapid burst of ROS production, heat stress also downregulates genes for pyruvate consumption. The accumulating pyruvate is the fastest acting of several M. robertsii ROS scavengers, efficiently reducing protein carbonylation, stabilizing mitochondrial membrane potential, and promoting fungal growth. The acetate produced from pyruvate-ROS reactions itself causes acid stress, tolerance to which is regulated by Hog1 mitogen-activated protein kinase. Heat stress also induces pyruvate accumulation in several other fungi, suggesting that scavenging of heat-induced ROS by pyruvate is widespread. IMPORTANCE Heat is a dangerous challenge for most organisms, as it denatures proteins and induces the production of ROS that inactivate proteins, lipid membranes, and DNA. How organisms respond to this stress is not fully understood. Using the experimentally tractable insect pathogen Metarhizium robertsii as a model organism, we show for the first time that heat stress induces pyruvate production and that this functions as the first line of defense against heat-induced ROS. Heat stress also induces rapid pyruvate accumulation in other fungi, suggesting that pyruvate is a common but unappreciated defense against stress. Heat is a dangerous challenge for most organisms, as it denatures proteins and induces the production of ROS that inactivate proteins, lipid membranes, and DNA. How organisms respond to this stress is not fully understood. Using the experimentally tractable insect pathogen Metarhizium robertsii as a model organism, we show for the first time that heat stress induces pyruvate production and that this functions as the first line of defense against heat-induced ROS. Heat stress also induces rapid pyruvate accumulation in other fungi, suggesting that pyruvate is a common but unappreciated defense against stress.