Characterization of Prophenoloxidase in Resisting Adverse Stresses in Apis cerana cerana

摘要

Insect prophenoloxidases (PPOs) are a group of important innate immunity proteins and play an important role in melanin synthesis, defending the intruding microorganisms and parasites, healing wound and cuticle pigmentation. However, there is little study about immune-related defense mechanisms in Apis cerana cerana. Here we isolated a PPO gene from A. cerana cerana and evaluated the connection of AccPPO to immunity. AccPPO has an open reading frame of 2079 bp encoding a 693 amino acid protein. The genomic structure analysis showed that AccPPO is similar to that of AmPPO. AccPPO is also close to AmPPO in the evolutionary period. AccPPO expression could be detected in all the developmental stages of A. cerana cerana and was the highest in 15-day postemergence adults. In addition, we also found that AccPPO was induced by the infection of Ascosphaera apis and various oxidative stresses including 4, 16°C; UV light; and pesticides (acaricide, cyhalothrin, paraquat) treatments. These results revealed that AccPPO may play a critical role in resisting Ascosphaera apis and preventing A. cerana cerana from oxidative stresses.