Prokaryotes encounter constant and often brutal modifications to their environment. In order to survive, they need to maintain fitness, which includes adapting their protein expression patterns. Many factors control gene expression but this review focuses on just one, namely antisense RNAs (asRNAs), a class of non-coding RNAs (ncRNAs) characterized by their location in cis and their perfect complementarity with their targets. asRNAs were considered for a long time to be trivial and only to be found on mobile genetic elements. However, recent advances in methodology have revealed that their abundance and potential activities have been underestimated. This review aims to illustrate the role of asRNA in various physiologically crucial functions in both archaea and bacteria, which can be regrouped in three categories: cell maintenance, horizontal gene transfer and virulence. A literature survey of asRNAs demonstrates the difficulties to characterize and assign a role to asRNAs. With the aim of facilitating this task, we describe recent technological advances that could be of interest to identify new asRNAs and to discover their function.

中文翻译：

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反义RNA在原核生物中的生理作用。

原核生物经常遭受对其环境不断且残酷的改造。为了生存，他们需要保持健康，包括适应其蛋白质表达方式。许多因素控制着基因的表达，但本文仅侧重于一个方面，即反义RNA（asRNA），一类非编码RNA（ncRNA），其特征在于它们在顺式中的位置以及与靶标的完美互补性。长期以来，人们一直认为asRNA是微不足道的，只能在可移动的遗传元件上发现。但是，方法学的最新进展表明，其数量和潜在活动被低估了。这篇综述旨在说明asRNA在古细菌和细菌的各种生理关键功能中的作用，这些功能可分为三类：细胞维持，基因水平转移和毒力。对asRNA的文献调查表明，难以表征和分配asRNA的作用。为了简化这项任务，我们描述了最近的技术进步，这些技术进步对于识别新的asRNA和发现其功能可能是有意义的。