HCV plays with fire and yet avoids getting burned. A review for clinicians on processing bodies and stress granules.

Over the last few years, many reports have defined several types of RNA cell granules composed of proteins and messenger RNA (mRNA) that regulate gene expression on a post-transcriptional level. Processing bodies (P-bodies) and stress granules (SGs) are among the best-known RNA granules, only detectable when they accumulate into very dynamic cytosolic foci. Recently, a tight association has been found between positive-stranded RNA viruses, including hepatitis C virus (HCV), and these granules. The present article offers a comprehensive review on the complex and paradoxical relationship between HCV, P-bodies and SGs from a translational perspective. Despite the fact that components of P-bodies and SGs have assiduously controlled mRNA expression, either by sequestration or degradation, for thousands of years, HCV has learned how to dangerously exploit certain of them for its own benefit in an endless biological war. Thus, HCV has gained the ability to hack ancient host machineries inherited from prokaryotic times. While P-bodies and SGs are crucial to the HCV cycle, in the interferon-free era we still lack detailed knowledge of the mechanisms involved, processes that may underlie the long-term complications of HCV infection.