De Herdt E, De Voeght F, Clauwaert J, Kondo M, Slegers H
Biochem J. 1981 Jan 15;194(1):9-17. doi: 10.1042/bj1940009.
The postribosomal supernatant of Artemia salina cryptobiotic embryos contains a large quantity of a 19S protein complex. An amount of 3.6 mg/g of cysts is measured by immunoprecipitation with anti-(19S protein complex) antibody. The quantity of this complex decreases during further development to nauplius larvae to only 15% of the quantity present in cryptobiotic embryos. The complex was no longer detectable after 7 days of growth. The 27000-Mr protein subunit of the 19S complex is not synthesized by mRNA isolated from cryptobiotic embryos. The cryptobiosis-specific complex has Mr 573000 and 610000 as calculated from light-scattering and sedimentation-diffusion measurements respectively. The 19S homocomplex contains 20-23 27000-Mr proteins and has no function in the translation of homologous mRNA. From hydrodynamic data a hydration of 1.25 g of water/g of protein is calculated. The abundant presence of the 19S protein complex in cryptobiotic embryos and the absence of synthesis during development to nauplius larvae indicate a functional role during the cryptobiotic process in early embryogenesis. A role in maintaining the water content of the cytoplasm above a critical threshold during desiccation is suggested.
卤虫隐生胚胎的核糖体后上清液中含有大量19S蛋白复合物。用抗（19S蛋白复合物）抗体进行免疫沉淀法测得，每克包囊中有3.6毫克该复合物。在进一步发育成无节幼虫的过程中，这种复合物的量减少，仅为隐生胚胎中该复合物量的15%。生长7天后就不再能检测到该复合物。19S复合物的27000道尔顿蛋白亚基不是由从隐生胚胎中分离出的mRNA合成的。根据光散射和沉降扩散测量分别计算得出，这种隐生特异性复合物的分子量为573000和610000。19S同源复合物含有20 - 23个27000道尔顿的蛋白，在同源mRNA的翻译过程中无功能。根据流体动力学数据计算得出，每克蛋白质结合1.25克水。隐生胚胎中大量存在19S蛋白复合物，而在发育成无节幼虫的过程中不进行合成，这表明其在早期胚胎发育的隐生过程中发挥功能作用。有人提出它在干燥过程中维持细胞质含水量高于临界阈值方面发挥作用。
