Sen George L, Blau Helen M
Department of Molecular Pharmacology, 269 Campus Drive, CCSR 4225A, Stanford University School of Medicine, Stanford, CA 94305, USA.
Nat Cell Biol. 2005 Jun;7(6):633-6. doi: 10.1038/ncb1265. Epub 2005 May 22.
RNA interference (RNAi) is an important means of eliminating mRNAs, but the intracellular location of RNA-induced silencing complex (RISC) remains unknown. We show here that Argonaute 2, a key component of RISC, is not randomly distributed but concentrates in mRNA decay centres that are known as cytoplasmic bodies. The localization of Argonaute 2 in decay centres is not altered by the presence or absence of small interfering RNAs or their targeted mRNAs. However, RNA is required for the integrity of cytoplasmic bodies because RNase eliminates Argonaute 2 localization. In addition, Argonaute 1, another Argonaute family member, is concentrated in cytoplasmic bodies. These results provide new insight into the mechanism of RNAi function.
RNA干扰（RNAi）是消除mRNA的重要手段，但RNA诱导沉默复合体（RISC）在细胞内的定位仍然未知。我们在此表明，RISC的关键组分AGO2并非随机分布，而是集中在被称为细胞质体的mRNA降解中心。AGO2在降解中心的定位不会因小干扰RNA或其靶向mRNA的存在与否而改变。然而，RNA对于细胞质体的完整性是必需的，因为核糖核酸酶会消除AGO2的定位。此外，另一个AGO家族成员AGO1也集中在细胞质体中。这些结果为RNAi功能机制提供了新的见解。
