An exosome-like complex in Sulfolobus solfataricus
An exosome-like complex in Sulfolobus solfataricus
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DOI：
10.1038/sj.embor.embor929
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发表时间：
2003-09-01
期刊：
影响因子：
7.7
通讯作者：
Klug, G
中科院分区：
文献类型：
--
作者：
Evguenieva-Hackenberg, E;Walter, P;Klug, G
我们提出了古细菌中存在外泌体样蛋白复合物的第一个实验证据。在真核生物中，外泌体在RNA加工和降解的许多途径中都是必不可少的。与先前预测的solfataricus外胞体亚基核糖体- rna加工蛋白41 （Rrp41）同源物的抗体共免疫沉淀，从solfataricus中纯化了250 kda的蛋白复合物。大约一半的复合共沉淀物具有核糖体亚基。它包括四个先前预测的酵母核心外泌体亚基的同源物（Rrp41, Rrp42， Rrp4和Csl4 （cep1合成致死4；一种rna结合蛋白和外泌体亚基）），而其他预测的亚基未被发现。令人惊讶的是，细菌DNA引物酶DnaG的古细菌同源物与该复合物密切相关。这表明古细菌dna样蛋白具有rna相关功能。来自不同生物体的实验数据的比较表明，外泌体的最小核心由至少一种磷酸依赖性核糖核酸酶PH同源物组成，并且由Rrp4和Csl4组成。这种蛋白质复合物可能存在于古细菌和真核生物最后的共同祖先中。
We present the first experimental evidence for the existence of an exosome-like protein complex in Archaea. In Eukarya, the exosome is essential for many pathways of RNA processing and degradation. Co-immunoprecipitation with antibodies directed against the previously predicted Sulfolobus solfataricus orthologue of the exosome subunit ribosomal-RNA-processing protein 41 (Rrp41) led to the purification of a 250-kDa protein complex from S. solfataricus. Approximately half of the complex cosediments with ribosomal subunits. It comprises four previously predicted orthologues of the core exosome subunits from yeast (Rrp41, Rrp42, Rrp4 and Csl4 (cep1 synthetic lethality 4; an RNA-binding protein and exosome subunit)), whereas other predicted subunits were not found. Surprisingly, the archaeal homologue of the bacterial DNA primase DnaG was tightly associated with the complex. This suggests an RNA-related function for the archaeal DnaG-like proteins. Comparison of experimental data from different organisms shows that the minimal core of the exosome consists of at least one phosphate-dependent ribonuclease PH homologue, and of Rrp4 and Csl4. Such a protein complex was probably present in the last common ancestor of Archaea and Eukarya.