The term “prion” was originally coined to describe the proteinaceous infectious agents involved in mammalian neurological disorders. More recently, a prion has been defined as a nonchromosomal, protein-based genetic element that is capable of converting the copies of its own benign variant into the prion form, with the new phenotypic effects that can be transmitted through the cytoplasm. Some prions are toxic to the cell, are able to aggregate and/or form amyloid structures, and may be infectious in the wild, but none of those traits are seen as an integral property of all prions. We propose that the definition of prion should be expanded, to include the inducible transmissible entities undergoing autocatalytic conversion and consisting of RNA rather than protein. We show that when seen in this framework, some naturally occurring RNAs, including ribozymes, riboswitches, viroids, viroid-like retroelements, and PIWI-interacting RNAs (piRNAs), possess several of the characteristic properties of prions.

中文翻译：

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表现得像朊病毒的 RNA。

术语“朊病毒”最初是用来描述哺乳动物神经系统疾病中涉及的蛋白质感染因子。最近，朊病毒被定义为一种非染色体的、基于蛋白质的遗传元件，能够将其自身良性变异体的拷贝转化为朊病毒形式，并具有可以通过细胞质传播的新表型效应。一些朊病毒对细胞有毒，能够聚集和/或形成淀粉样蛋白结构，并且在野外可能具有传染性，但这些特征中没有一个被视为所有朊病毒的一个组成部分。我们建议应该扩大朊病毒的定义，以包括经历自催化转化并由 RNA 而不是蛋白质组成的诱导型可传播实体。我们表明，当在这个框架中看到时，一些天然存在的 RNA，