Phosphorylation inhibits the activity of μ-calpain at different incubation temperatures and Ca2+ concentrations in vitro. (1st August 2017)

• Record Type: Journal Article
• Authors: Du, Manting; Li, Xin; Li, Zheng; Li, Meng; Gao, Lingling; Zhang, Dequan
• Is Part Of: Food chemistry. Volume 228(2017)
• Page Start: 649
• Page End: 655
• Publication Date: 2017-08-01
• Subjects: Mutton -- μ-Calpain -- Phosphorylation -- Temperature -- Calcium; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2017.02.003
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: The effect of phosphorylation on the activity of μ-calpain was detected in vitro . Incubation at 25 °C could diminish the influence of phosphorylation on μ-calpain. Increased Ca 2+ concentration shrinks the effects caused by phosphorylation. Phosphorylation may play a negative role in regulating μ-calpain activity. The activity of m-calpain was also influenced by phosphorylation. Abstract: This study aimed to investigate the effects of phosphorylation on the activity of μ-calpain and its sensitivity to temperature and Ca 2+ . For temperature sensitivity analysis, sarcoplasmic protein was treated with alkaline phosphatase (AP) and phosphatase inhibitor (PI) at 4, 25 and 37 °C. The results showed that the degradation degree of μ-calpain in the AP group was significantly higher after incubation for 12 h. For calcium sensitivity analysis, samples treated with AP and PI were incubated at 0.01, 0.05, 0.1 and 1 mM Ca 2+ . The results showed that the degradation rate of μ-calpain was maximum in the AP group and minimum in the PI group at 0.01, 0.05 and 0.1 mM Ca 2+ . The differences between the three groups reduced as concentration increased. These data demonstrate that phosphorylation plays a negative role in regulating μ-calpain activity. This study clarifies the regulatory mechanism of μ-calpain activation in vitro and/or in postmortem muscle.