Recent mass mortality outbreaks around the world in Pacific oysters, Crassostrea gigas, have seriously affected the aquaculture economy. Although the causes for these mortality outbreaks appear complex, infectious agents are involved. Two pathogens are associated with mass mortality outbreaks, the virus ostreid herpesvirus 1 (OsHV-1) and the bacterium Vibrio aestuarianus. Here we describe the interactions between these 2 pathogens and autophagy, a conserved intracellular pathway playing a key role in innate immunity. We show for the first time that autophagy pathway is present and functional in Pacific oysters and plays an important role to protect animals from infections. This study contributes to better understand the innate immune system of Pacific oysters.
Keywords: ATG, autophagy-related; Atg8–PE, Atg8–phosphatidylethenolamine; Crassostrea gigas; DNA, deoxyribonucleic acid; LC3-II, cleaved, lipidated and autophagosome-associated form of LC3; MAP1LC3A/B (LC3A/B), microtubule-associated proteins 1 light chain 3 alpha/beta (mammalian orthologs of the predicted Crassostrea gigas LC3 and yeast Atg8); NH4Cl, ammonium chloride; OsHV-1; OsHV-1, Ostreid herpesvirus 1; PCR, polymerase chain reaction; Pacific oyster; Vibrio aestuarianus; autophagy; hpi, hours postinfection.