College of Environmental Science and Engineering, Ocean University of China, Qingdao, Shandong, P.R. China.
National Marine Hazard Mitigation Service, Beijing, China.
Sci Rep. 2017 May 8;7(1):1558. doi: 10.1038/s41598-017-01318-x.
Few studies have been published on the mechanisms of hypoxia response and tolerance in jellyfish, especially with respect to the regulatory mechanism at the molecular level. In this study, Aurelia sp.1, which is frequently found in Chinese coastal waters, was cultivated in a hypoxic system to determine the molecular mechanisms underlying its hypoxic response by studying the physiological activity, gene expression and metabolite contents in the prolyl hydroxylase domain (PHD)-hypoxia inducible factor (HIF) oxygen-sensing system. Physiological activity; the expression of PHD, HIF, ALDO (fructose-bisphosphate aldolase), PDK (pyruvate dehydrogenase kinase), and LDH (lactate dehydrogenase) genes; and the lactic acid content in medusae were significantly affected by hypoxia. The up-regulation of ALDO, PDK and LDH, which was directly or indirectly induced by HIF, mediated the transition from aerobic respiration to anaerobic glycolysis in the medusae. In polyps, there was a slight increase in the expression of HIF, PHD and ALDO, no obvious change in that of PDK and a slight decrease in that of LDH throughout the experiment; however, these changes were insufficient to induce the shift. This study provides a scientific basis for elucidating the regulatory mechanism underlying the PHD-HIF oxygen-sensing system in Aurelia sp.1.
关于水母缺氧反应和耐受机制的研究较少，尤其是在分子水平的调控机制方面。本研究以我国近海常见的海月水母（ Aurelia sp.1 ）为实验材料，在缺氧系统中进行培养，通过研究脯氨酰羟化酶结构域（PHD）-低氧诱导因子（HIF）氧感应系统中生理活性、基因表达和代谢物含量的变化，探讨其缺氧反应的分子机制。结果表明，缺氧显著影响水母的生理活性、PHD、HIF、醛缩酶（ALDO）、丙酮酸脱氢酶激酶（PDK）和乳酸脱氢酶（LDH）基因的表达以及水母体内的乳酸含量。HIF 直接或间接诱导的 ALDO、PDK 和 LDH 的上调介导了水母从有氧呼吸向无氧糖酵解的转变。在水螅体中，HIF、PHD 和 ALDO 的表达略有增加，PDK 的表达无明显变化，LDH 的表达略有下降，但这些变化不足以诱导转变。本研究为阐明海月水母 PHD-HIF 氧感应系统的调控机制提供了科学依据。
