The mechanism of RNase III action: how dicer dices.
The mechanism of RNase III action: how dicer dices.
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RNase III 作用机制：切丁机如何切丁。
DOI：
10.1007/978-3-540-75157-1_5
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发表时间：
2008
影响因子：
--
通讯作者：
Ji,Xinhua
中科院分区：
文献类型：
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作者：
Ji,Xinhua
核糖核酸酶III（Ribonuclease III，RNase III）家族成员是双链RNA特异性内切核糖核酸酶，其特征是在其活性中心有一个特征基序，在其产物中有一个2-核苷酸（nt）的3′突出端。Dicer作为dsRNA加工酶发挥作用，产生约100 μ g的小干扰RNA（siRNA）。24 nt长度（大约）20-碱基对RNA双链体，每个末端上具有2-nt 3′突出端）。细菌RNase III不仅作为一种加工酶，而且作为一种结合蛋白，它结合dsRNA而不切割它。13 nt的长度（约。9-碱基对双链体，每个末端有一个2-nt的3′突出端）以及各种类型的成熟RNA。Dicer是结构上最复杂的家族成员;细菌RNase III相对简单得多。已知Dicer的一种结构是其无RNA形式（MacRae，Zhou，Li，Repic，布鲁克斯，Cande，亚当斯和Doudna，科学311：195-198）;许多结构可用于细菌RNA酶III，包括
Members of the Ribonuclease III (RNase III) family are double-stranded (ds) RNA-specific endoribonucleases, characterized by a signature motif in their active centers and a 2-nucleotide (nt) 3′ overhang in their products. Dicer functions as a dsRNA-processing enzyme, producing small interfering RNA (siRNA) of approx. 24 nt in length (approx. 20-basepair RNA duplex with a 2-nt 3′ overhang on each end). Bacterial RNase III functions not only as a processing enzyme, but also as a binding protein that binds dsRNA without cleaving it. As a processing enzyme it produces siRNA-like RNA of approx. 13 nt in length (approx. 9-basepair duplex with a 2-nt 3′ overhang on each end) as well as various types of mature RNA. Dicer is structurally most complicated member of the family; bacterial RNase III is comparatively much simpler. One structure is known for Dicer in its RNA-free form (MacRae, Zhou, Li, Repic, Brooks, Cande, Adams, and Doudna, Science 311: 195–198); many structures are available for bacterial RNase III, including the