# Carrot and stick: how RNase R contributes to function and destruction of the translation machinery

## TL;DR

This paper reviews how the enzyme RNase R helps regulate and break down RNA components involved in protein translation in bacteria.

## Contribution

The paper highlights new structural insights into RNase R's role in RNA homeostasis and translation machinery regulation.

## Key findings

- RNase R regulates and degrades components of the bacterial translation machinery.
- Recent structural studies reveal new details about RNase R's enzymatic activities.
- The enzyme plays a key role in trans-translation system regulation.

## Abstract

RNA is fundamental for life, and its homoeostasis is a critical contributor to cellular growth and adaptation to stress. Key RNA species include messenger RNA (mRNA) and non-coding RNAs, such as transfer RNA (tRNA), or ribosomal RNA (rRNA), that are essential for ribosome formation and translation of the genetic code. Furthermore, various other non-coding RNAs are expressed at each growth stage. Given RNA’s abundance and its role in all cellular processes, RNases – enzymes responsible for RNA degradation and processing – are central to RNA metabolism. In this review, we discuss the pivotal contribution of the 3’ exonuclease RNase R to bacterial RNA homoeostasis. We focus on its functions in regulating and degrading components of the translation machinery, including the trans-translation system, and we take a look at recent structural studies that shed new light on the activities of this important enzyme.