Wang Zhenxin, Xing Tong, Zhang Lin, Zhao Liang, Gao Feng
College of Animal Science and Technology, Key Laboratory of Animal Origin Food Production and Safety Guarantee of Jiangsu Province, Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China.
College of Animal Science and Technology, Key Laboratory of Animal Origin Food Production and Safety Guarantee of Jiangsu Province, Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China.
Poult Sci. 2024 Dec;103(12):104354. doi: 10.1016/j.psj.2024.104354. Epub 2024 Sep 24.
This experiment aimed to reveal the dynamic changes of protein post-translational lactylation modifications and their correlations with the glycolytic process in broiler breast muscle within 48 h of postmortem acidification. The experiment involved 12 male AA broilers, 42 days old, with similar body weights (2.8 ± 0.05 kg). The breast fillets (Pectoralis major) were collected after slaughter, and samples were taken at various time points: 0, 15 min, 30 min, 45 min, 60 min, 2 h, 4 h, 6 h, 8 h, 12 h, 18 h, 24 h, 36 h, and 48 h postmortem. The results showed that the rate of glycogen decline in the muscle was highest at 45 min postmortem, and glycogen levels tended to stabilize at 8 h postmortem. The lactate content in the breast reached its highest level at 4 h postmortem and began to decrease, stabilizing at 24 h postmortem. Additionally, the glycolytic potential increased gradually in the first 4 h postmortem, decreased rapidly from 4 to 8 h. Similarly, lactylation modification levels were highest at 8 h postmortem, but stabilized at 12 h postmortem. During this process, the protein expression of the enzymatic lactylation modifier p300 showed no significant difference, while the content of the nonenzymatic lactylation substrate lactoylglutathione significantly decreased at 8 h and 24 h postmortem. Correlation analysis found that lactylation levels were negatively correlated with glycogen content, glucose content, glycolytic potential, and pH value, while positively correlated with lactate content. Besides, there was a positive correlation between lactylation levels and the protein expression of hexokinase, phosphoglycerate kinase 2, phosphoglucomutase 1, and triosephosphate isomerase. Additionally, lactylation levels were positively correlated with the activities of lactate dehydrogenase and phosphofructokinase. In summary, our experiment elucidated the dynamic changes in the entire glycolytic pathway in broiler pectoral muscle during acidification. During this process, lactylation modifications may participate in the glycolysis process by regulating the protein expression and activity of glycolytic enzymes.
本实验旨在揭示宰后48小时内肉鸡胸肌蛋白质翻译后乳酰化修饰的动态变化及其与糖酵解过程的相关性。实验选用12只42日龄、体重相近（2.8±0.05千克）的雄性AA肉鸡。屠宰后采集胸肌（胸大肌），并在宰后不同时间点取样：0、15分钟、30分钟、45分钟、60分钟、2小时、4小时、6小时、8小时、12小时、18小时、24小时、36小时和48小时。结果表明，宰后45分钟时肌肉中糖原下降速率最高，宰后8小时糖原水平趋于稳定。胸肌中乳酸含量在宰后4小时达到最高水平，随后开始下降，在宰后24小时稳定。此外，宰后前4小时糖酵解潜能逐渐增加，4至8小时迅速下降。同样，乳酰化修饰水平在宰后8小时最高，但在宰后12小时稳定。在此过程中，酶促乳酰化修饰因子p300的蛋白质表达无显著差异，而非酶促乳酰化底物乳酰谷胱甘肽的含量在宰后8小时和24小时显著下降。相关性分析发现，乳酰化水平与糖原含量、葡萄糖含量、糖酵解潜能和pH值呈负相关，与乳酸含量呈正相关。此外，乳酰化水平与己糖激酶、磷酸甘油酸激酶2、磷酸葡萄糖变位酶1和磷酸丙糖异构酶的蛋白质表达呈正相关。另外，乳酰化水平与乳酸脱氢酶和磷酸果糖激酶的活性呈正相关。总之，我们的实验阐明了宰后酸化过程中肉鸡胸肌整个糖酵解途径的动态变化。在此过程中，乳酰化修饰可能通过调节糖酵解酶的蛋白质表达和活性参与糖酵解过程。
