Viruses Utilize Cellular Cues in Distinct Combination to Undergo Systematic Priming and Uncoating.

Abstract

Viral genomes are protected within a proteinaceous shell called “capsid” and, for enveloped viruses, an additional lipid coat. The capsids are generally constructed from a few capsid proteins into helical or icosahedral structures that are, in turn, stabilized by numerous covalent and noncovalent interactions [1]. However, during infection, viruses must uncoat in order to release their genomes into the host. This process is highly dependent on host elements called “cues” [2], which have been previously broadly categorized as (1) receptor- and/or enzyme-based cues, (2) chemical cues, or (3) mechanical cues [3]. In this brief article, we systematically analyze the available information on how 30 different enveloped and nonenveloped viruses exploit these host cues during infection and tabulate the observations in Table 1. By categorizing these cues, a general pattern can be deduced. Specifically, we find that these viruses use a distinct order and combination of the host cues during entry. To illustrate this principle, the mechanism by which four viruses hijack these cues will be highlighted (in Fig 1). We envision such analysis will provide an opportunity for investigators to evaluate whether viruses within the same family—for which the uncoating mechanism is unknown—employ a similar uncoating strategy.