Lysine acetylation in the allograft-induced stress response of Pinctada fucata martensii

The pearl oyster, Pinctada fucata martensii, can experience transplant rejection or even host death following allografting. This study analyzed the impact of increased protein acetylation on the immune response of P. f. martensii after implantation, aiming to investigate the role of acetylation modifications after implantation. In this study, a mixture of broad-spectrum lysine deacetylase inhibitors (KDI) was injected into P. f. martensi assess the impact of increased protein acetylation through multiple analytical methods, including Real-time PCR (qRT-PCR), western blot (WB), antioxidant enzyme activity assay, and culture indicators. After the stimulation of KDI, the relative expression of HDAC 6/10 (10006221), the two numbers of the family of Sir2(10031932 and 10020349) were significantly down-regulated at different time points, while the acetylation level of total proteins in the gills was significantly increased at 72 h, indicating a marked enhancement of protein acetylation in the gill tissue following injection. Additionally, the results showed that the expression of IRAK1, IL-17, NF-κB, and CASP2 were all significantly up-regulated at 12 h, IκK was significantly up-regulated at 48 h. Meanwhile, TRAF3 expression was significantly downregulated from 48 h onward, collectively suggesting that KDI stimulation enhanced cellular immunity in the recipient oysters. Furthermore, antioxidant enzymes such as GSH-Px, POD, and CAT were significantly upregulated at 12 and 24 h post-KDI treatment, indicating an enhancement of humoral immunity. Lastly, the results showed that after KDI stimulation, the retention rate and survival rate were significantly up-regulation at 60 d compared to the blank group. These results suggest that acetylation modification plays a key role in allograft-induced stress in P. f. martensii , and KDI may serve as an immunomodulator to regulate the implantation process. In summary, this study provides an important basis for in-depth exploration of the immune response and adaptive mechanisms initiated by acetylation modifications in pearl oysters during implantation, and theoretical support for the rational control of the immune response of pearl oysters.