Department of Biological Sciences, University of Windsor, Windsor, ON N9B 3P4, Canada.
J Biochem. 2010 Nov;148(5):581-92. doi: 10.1093/jb/mvq091. Epub 2010 Aug 17.
The presence of late embryogenesis abundant (LEA) proteins in plants and animals has been linked to their ability to tolerate a variety of environmental stresses. Among animals, encysted embryos of the brine shrimp Artemia franciscana are among the most stress resistant eukaryotes, and for that reason it is considered to be an extremophile. The study presented here demonstrates that these embryos contain multiple group 1 LEA proteins with masses of 21, 19, 15.5 and 13 kDa. The LEA proteins first appear in diapause-destined embryos, beginning at ∼4 days post-fertilization, but not in nauplii-destined embryos. After resumption of embryonic development, the LEA proteins decline slowly in the desiccation resistant encysted stages, then disappear rapidly as the embryo emerges from its shell. LEA proteins are absent in fully emerged embryos, larvae and adults. They are abundant in mitochondria of encysted embryos, but barely detectable in nuclei and absent from yolk platelets. LEA proteins were also detected in dormant embryos of six other species of Artemia from hypersaline environments around the world. This study enhances our knowledge of the group 1 LEA proteins in stress tolerant crustacean embryos.
植物和动物中晚期胚胎丰富（LEA）蛋白的存在与它们耐受各种环境压力的能力有关。在动物中，卤虫 Artemia franciscana 的包囊胚胎是最具抗逆性的真核生物之一，因此被认为是一种极端生物。本研究表明，这些胚胎含有多种质量为 21、19、15.5 和 13 kDa 的第 1 组 LEA 蛋白。LEA 蛋白首先出现在处于休眠状态的胚胎中，大约在受精后 4 天开始，但不出现在处于无节幼体状态的胚胎中。胚胎发育恢复后，LEA 蛋白在抗干燥的包囊阶段缓慢下降，然后随着胚胎从壳中孵出迅速消失。LEA 蛋白在完全孵出的胚胎、幼虫和成虫中不存在。它们在包囊胚胎的线粒体中大量存在，但在核中几乎检测不到，在卵黄小板中不存在。在来自世界各地高盐环境的六种其他卤虫休眠胚胎中也检测到了 LEA 蛋白。本研究增强了我们对耐应激甲壳类动物胚胎中第 1 组 LEA 蛋白的认识。
