The subcellular localization of a biopolymer often informs its function. RNA is traditionally confined to the cytosolic and nuclear spaces, where it plays critical and conserved roles across nearly all biochemical processes. Our recent observation of cell surface glycoRNAs may further explain the extracellular role of RNA. While cellular membranes are efficient gatekeepers of charged polymers such as RNAs, a large body of research has demonstrated the accumulation of specific RNA species outside of the cell, termed extracellular RNAs (exRNAs). Across various species and forms of life, protein pores have evolved to transport RNA across membranes, thus providing a mechanistic path for exRNAs to achieve their extracellular topology. Here, we review types of exRNAs and the pores capable of RNA transport to provide a logical and testable path toward understanding the biogenesis and regulation of cell surface glycoRNAs.

中文翻译：

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RNA 跨膜：细胞外 RNA 和细胞表面 GlycoRNA 的系统和机制

生物聚合物的亚细胞定位通常决定其功能。 RNA 传统上局限于细胞质和核空间，在几乎所有生化过程中发挥着关键和保守的作用。我们最近对细胞表面糖RNA的观察可能会进一步解释RNA的细胞外作用。虽然细胞膜是 RNA 等带电聚合物的有效看门人，但大量研究已经证明特定 RNA 种类在细胞外积累，称为细胞外 RNA (exRNA)。在不同的物种和生命形式中，蛋白质孔已经进化为跨膜运输RNA，从而为exRNA实现其细胞外拓扑结构提供了机械路径。在这里，我们回顾了 exRNA 的类型和能够进行 RNA 运输的孔，为理解细胞表面糖 RNA 的生物发生和调控提供了一条逻辑且可测试的途径。