When specific bacteria invade host cells through endocytosis/phagocytosis, a selective type of autophagy termed xenophagy, engulfs them to restrict their growth [184] (Figure 3(d) ). Although neither the target proteins nor the E3 ligases have yet been identified, invading bacteria such as Salmonella enterica, Listeria monocytogenes, or Shigella flexneri become positive for ubiquitin when they access the cytosol by rupturing the endosome/phagosome limiting membrane [185, 186] . These findings raise the possibility that ubiquitin also serves as a tag during xenophagy. In fact, to date, three proteins, p62 [105, 185, 187] , NDP52 [188] , and optineurin [115] have been proposed to be autophagy receptors linking ubiquitinated bacteria and LC3. An ubiquitin-independent mechanism has recently been revealed; recognition of a Shigella mutant that lacks the icsB gene requires the tectonin domaincontaining protein 1 (Tecpr1), which appears to be a new type of autophagy adaptor targeting Shigella to Atg5-and WIPI-2-positive membranes [189] . Interestingly, the Shigella icsB normally prevents autophagic sequestration of this bacterium by inhibiting the interaction of Shigella VirG with Atg5 indicating that some bacteria have developed mechanism to inhibit or subvert autophagy to their advantage [190] . This latter category of pathogens also includes viruses such as Herpes simplex virus-1 (HSV-1), which express an inhibitor (ICP34.5) of Atg6/Beclin1 [106] . However, it was recently shown that a mutant HSV-1 strain lacking ICP34.5 becomes degraded by selective autophagy in a SMURF1dependent manner [79] , suggesting that selective autophagy plays an important role in our immune system.