The double-stranded RNA-binding protein (dsRBP) family controls RNA editing, stability, and function in all eukaryotes. The central feature of this family is the recognition of a generic RNA duplex using highly conserved double-stranded RNA-binding domain (dsRBD) that recognizes the characteristic distance between the minor grooves created by the RNA helix. Variations on this theme that confer species and functional specificities have been reported but most dsRBPs retain their capacity to bind generic dsRNA. The ribonuclease III (RNase III) family members fall into four classes, represented by bacterial RNase III, yeast Rnt1p, human Drosha, and human Dicer, respectively. Like all dsRBPs and most members of the RNase III family, Rnt1p has a dsRBD, but unlike most of its kin, it poorly binds to generic RNA helices. Instead, Rnt1p, the only known RNase III expressed in Saccharomyces cerevisiae that lacks the RNAi (RNA interference) machinery, recognizes a specific class of stem-loop structures. To recognize the specific substrates, the dsRBD of Rnt1p is specialized, featuring a αβββααα topology and a sequence-specific RNA-binding motif at the C-terminus. Since the discovery of Rnt1p in 1996, significant progress has been made in studies of its genetics, function, structure, and mechanism of action, explaining the reasons and mechanisms for the increased specificity of this enzyme and its impact on the mechanism of RNA degradation. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Processing > Processing of Small RNAs RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.

中文翻译：

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Rnt1p的结构和功能：靶向RNA降解的RNAi替代品。

双链RNA结合蛋白（dsRBP）家族控制所有真核生物中的RNA编辑，稳定性和功能。该家族的主要特征是使用高度保守的双链RNA结合结构域（dsRBD）识别通用RNA双链体，该结构域识别由RNA螺旋产生的小沟之间的特征距离。已经报道了赋予物种和功能特异性的该主题的变体，但是大多数dsRBP保留了它们结合通用dsRNA的能力。核糖核酸酶III（RNase III）家族成员分为四类，分别由细菌RNase III，酵母Rnt1p，人Drosha和人Dicer代表。与所有dsRBP和RNase III家族的大多数成员一样，Rnt1p具有dsRBD，但与大多数亲属不同，它与普通RNA螺旋的结合较弱。而是Rnt1p，在酿酒酵母中表达的唯一已知的缺少RNAi（RNA干扰）机制的RNase III可以识别一类特定的茎环结构。为了识别特定的底物，Rnt1p的dsRBD经过专门化处理，具有一个αβββααα拓扑结构，并在C端具有序列特异性RNA结合基序。自从1996年发现Rnt1p以来，在其遗传学，功能，结构和作用机制方面的研究已取得了重大进展，解释了该酶特异性增加的原因和机制及其对RNA降解机制的影响。本文归类于：RNA周转和监视>周转/监视机制RNA与蛋白质和其他分子的相互作用>蛋白质-RNA识别RNA加工>