The annual killifish, Austrofundulus limnaeus, survives in ephemeral ponds in the coastal deserts of Venezuela. Persistence through the dry season is dependent on drought-resistant eggs embedded in the pond sediments during the rainy season. The ability of these embryos to enter drastic metabolic dormancy (diapause) during normal development enables A. limnaeus to survive conditions lethal to most other aquatic vertebrates; critical to the survival of the species is the ability of embryos to survive months and perhaps years without access to liquid water. Little is known about the molecular mechanisms that aid in survival of the dry season. This study aims to gain insight into the mechanisms facilitating survival of dehydration stress due to aerial exposure by examining metabolite profiles of dormant and developing embryos. There is strong evidence for unique metabolic profiles based on developmental stage and length of aerial exposure. Actively developing embryos exhibit more robust changes, however, dormant embryos respond in an active manner and significantly alter their metabolic profile. A number of metabolites accumulate in aerial-exposed embryos that may play an important role in survival, including the identification of known antioxidants and neuroprotectants. In addition, a number of unique metabolites not yet discussed in the dehydration literature are identified, such as lanthionine and 2-hydroxyglutarate. Despite high oxygen availability, embryos accumulate the anaerobic end-product lactate. This paper offers an overview of the metabolic changes occurring that may support embryonic survival during dehydration stress due to aerial incubation, which can be functionally tested using genetic and pharmacological approaches.

中文翻译：

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空中脱水胁迫下一年生幼鱼（Austrofundulus limnaeus）胚胎的代谢组学分析。

一年生的金鱼，Austrofundulus limnaeus，在委内瑞拉沿海沙漠的临时池塘中生存。整个干旱季节的持久性取决于在雨季嵌入池塘沉积物中的抗旱卵。这些胚胎在正常发育过程中进入剧烈的代谢休眠状态（停滞）的能力使A. limnaeus能够生存下来，对大多数其他水生脊椎动物具有致命的杀伤力。对于物种生存至关重要的是，胚胎在不接触液态水的情况下可以生存数月甚至数年的能力。关于有助于旱季生存的分子机制知之甚少。这项研究旨在通过检查休眠和发育中的胚胎的代谢产物概况，来了解促进因空气暴露而引起的脱水应激生存的机制。有充分的证据表明，基于发育阶段和暴露时间的长短，其独特的代谢特征。活跃发育的胚胎表现出更强大的变化，但是，休眠的胚胎以活跃的方式反应并显着改变其代谢特性。许多代谢产物积累在暴露于空气的胚胎中，可能在生存中起重要作用，包括鉴定已知的抗氧化剂和神经保护剂。另外，鉴定了脱水文献中尚未讨论的许多独特的代谢产物，例如羊毛硫氨酸和2-羟基戊二酸。尽管有大量的氧气，但胚胎会积累厌氧终产物乳酸。本文概述了可能发生的代谢变化，这些变化可能会由于空中孵育而在脱水胁迫期间支持胚胎的存活，