RNAs have highly complex and dynamic cellular localization patterns. Technologies for imaging RNA in living cells are important for uncovering their function and regulatory pathways. One approach for imaging RNA involves genetically encoding fluorescent RNAs using RNA mimics of green fluorescent protein (GFP). These mimics are RNA aptamers that bind fluorophores resembling those naturally found in GFP and activate their fluorescence. These RNA-fluorophore complexes, including Spinach, Spinach2, and Broccoli, can be used to tag RNAs and to image their localization in living cells. In this article, we describe the generation and optimization of these aptamers, along with strategies for expanding the spectral properties of their associated RNA-fluorophore complexes. We also discuss the structural basis for the fluorescence and photophysical properties of Spinach, and we describe future prospects for designing enhanced RNA-fluorophore complexes with enhanced photostability and increased sensitivity.

中文翻译：

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绿色荧光蛋白RNA模拟物的结构和机理。

RNA具有高度复杂和动态的细胞定位模式。活细胞中RNA成像技术对于揭示其功能和调节途径非常重要。成像RNA的一种方法涉及使用绿色荧光蛋白（GFP）的RNA模仿物对荧光RNA进行遗传编码。这些模拟物是RNA适体，可结合类似于GFP中天然存在的荧光团的荧光团并激活其荧光。这些RNA荧光团复合物，包括Spinach，Spinach2和Broccoli，可用于标记RNA并成像其在活细胞中的定位。在本文中，我们描述了这些适体的产生和优化，以及扩展其相关RNA荧光团复合物光谱特性的策略。