School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, PR China.
Bio-X institutes, Shanghai Jiao Tong University, Shanghai, PR China.
PLoS One. 2018 Jun 14;13(6):e0199056. doi: 10.1371/journal.pone.0199056. eCollection 2018.
Regulating the air in low-oxygen environments protects hermetically stored grains from storage pests damage. However, pests that can tolerate hypoxic stress pose a huge challenge in terms of grain storage. We used various biological approaches to determine the fundamental mechanisms of Tribolium castaneum to cope with hypoxia. Our results indicated that limiting the available oxygen to T. castaneum increased glycolysis and inhibited the Krebs cycle, and that accumulated pyruvic acid was preferentially converted to lactic acid via anaerobic metabolism. Mitochondrial aerobic respiration was markedly suppressed for beetles under hypoxia, which also might have led to mitochondrial autophagy. The enzymatic activity of citrate synthase decreased in insects under hypoxia but recovered within 12 h, which suggested that the beetles recovered from the hypoxia. Moreover, hypoxia-reperfusion resulted in severe oxidative damage to insects, and antioxidant levels increased to defend against the high level of reactive oxygen species. In conclusion, our findings show that mitochondria were the main target in T. castaneum in response to low oxygen. The beetles under hypoxia inhibited mitochondrial respiration and increased antioxidant activity after reoxygenation. Our research advances the field of pest control and makes it possible to develop more efficient strategies for hermetic storage.
调节低氧环境中的空气可以保护密封储存的谷物免受储存害虫的损害。然而，能够耐受缺氧应激的害虫对谷物储存构成了巨大挑战。我们使用各种生物学方法来确定赤拟谷盗应对缺氧的基本机制。研究结果表明，限制赤拟谷盗可利用的氧气会增加糖酵解并抑制三羧酸循环，并且积累的丙酮酸通过无氧代谢优先转化为乳酸。在低氧条件下，甲虫的线粒体需氧呼吸明显受到抑制，这也可能导致线粒体自噬。在缺氧条件下，昆虫中的柠檬酸合酶的酶活性下降，但在 12 小时内恢复，这表明甲虫从缺氧中恢复过来。此外，缺氧再灌注导致昆虫发生严重的氧化损伤，抗氧化剂水平升高以抵御高水平的活性氧。总之，我们的研究结果表明，在赤拟谷盗中，线粒体是对低氧的主要反应靶点。缺氧条件下的甲虫抑制线粒体呼吸，并在再氧化后增加抗氧化活性。我们的研究推进了害虫控制领域的发展，为密封储存开发更有效的策略成为可能。
