Łopieńska-Biernat Elżbieta, Stryiński Robert, Dmitryjuk Małgorzata, Wasilewska Barbara
Department of Biochemistry, Faculty of Biology and Biotechnology, University Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland
Department of Biochemistry, Faculty of Biology and Biotechnology, University Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719 Olsztyn, Poland.
Biol Open. 2019 Mar 21;8(3):bio040014. doi: 10.1242/bio.040014.
L3 larvae infect fish and other seafood species such as squid or octopi; therefore, humans consuming raw or undercooked fish may become accidental hosts for this parasite. These larvae are induced to enter hypometabolism by cold temperatures. It is assumed that sugars (in particular trehalose and glycogen) are instrumental for survival under environmental stress conditions. To elucidate the mechanisms of environmental stress response in , we observed the effects of starvation and temperature on trehalose and glycogen content, the activity of enzymes metabolizing those sugars, and the relative expression of genes of trehalose and glycogen metabolic pathways. The L3 of synthesize trehalose both in low (0°C) and high temperatures (45°C). The highest content of glycogen was observed at 45°C at 36 h of incubation. On the second day of incubation, tissue content of trehalose depended on the activity of the enzymes: TPS was more active at 45°C, and TPP was more active at 0°C. The changes in TPP activity were consistent with the transcript level changes of the TPP gene, and the trehalose level, while glycogen synthesis correlates with the expression of glycogen synthase gene at 45°C; this suggests that the synthesis of trehalose is more essential. These results show that trehalose plays a key role in providing energy during the thermotolerance and starvation processes through the molecular and biochemical regulation of trehalose and glycogen metabolism.
L3幼虫感染鱼类及其他海鲜物种，如鱿鱼或章鱼；因此，食用生的或未煮熟鱼类的人类可能会意外成为这种寄生虫的宿主。这些幼虫会因低温而进入低代谢状态。据推测，糖类（特别是海藻糖和糖原）在环境应激条件下的生存中起重要作用。为了阐明[寄生虫名称未给出]环境应激反应的机制，我们观察了饥饿和温度对海藻糖和糖原含量、代谢这些糖类的酶活性以及海藻糖和糖原代谢途径相关基因相对表达的影响。[寄生虫名称未给出]的L3幼虫在低温（0°C）和高温（45°C）下均能合成海藻糖。在45°C孵育36小时时观察到糖原含量最高。在孵育的第二天，海藻糖的组织含量取决于酶的活性：TPS在45°C时更活跃，TPP在0°C时更活跃。TPP活性的变化与TPP基因的转录水平变化以及海藻糖水平一致，而糖原合成在45°C时与糖原合酶基因的表达相关；这表明海藻糖的合成更为重要。这些结果表明，海藻糖通过对海藻糖和糖原代谢的分子及生化调节，在耐热性和饥饿过程中提供能量方面发挥关键作用。
