The itchy spots of chickenpox, a familiar scourge of childhood, are caused by infection with the varicella-zoster virus (VZV), an intriguing pathogen that can reactivate in adulthood to cause the more severe rashes of shingles. VZV shares many features with its close relative, the herpes virus, but one exception is their response to a host cell defence known as autophagy. In this process, virus particles are engulfed by small membrane sacs, or autophagosomes, and then destroyed. Herpes virus carries two genes which block autophagy, but VZV, with its much smaller genome, can’t resist this defence. Here, infected skin tissue, with nuclear DNA shown in blue and VZV particles in red, reveals an abundance of autophagosomes, highlighted in green. Understanding how VZV copes with autophagy, or perhaps uses it to further its own ends, will help expose the tactics of this widespread virus.
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BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.