Response of protein DJ-1 to oxidative stress in porcine longissimus thoracis and semimembranous muscles: Expression, oxidation, and protein interactions during postmortem aging

Reactive oxygen species (ROS) have been recognized to have a significant impact on meat quality, while the role of the antioxidant system in response to ROS in postmortem muscle remain unclear. Protein DJ-1 serves as a sensor of oxidative stress and has an antioxidant function in biological systems. Hence, this study aimed to investigate the expression, oxidation, and interaction of protein DJ-1 in porcine longissimus thoracis (LT) and semimembranous (SM) muscles, as well as its correlation with meat quality, to gain a better understanding of meat quality formation during postmortem aging. The findings indicated significant variations in pH, L*, a*, purge loss, cooking loss, and Warner-Bratzler shear force (WBSF) between the muscle groups (P < 0.05). The levels of reactive oxygen species (ROS), protein DJ-1, and oxidized DJ-1 (oxDJ-1) in SM muscle were higher than those in LT muscle throughout the 3 d of postmortem aging (P < 0.05). Moreover, protein DJ-1 and oxDJ-1 were significantly associated with water holding capacity and a* value of pork (P < 0.05). Through co-immunoprecipitation and mass spectrometry, a total of 23 DJ-1 interacting proteins were identified, mainly participating in glycolysis, energy metabolism, muscle contraction, resistance to oxidative stress, as well as amino acids biosynthesis and metabolism. These results suggest that DJ-1 may exert a regulatory influence on the development of pork quality during postmortem aging.