title: Phosphorylation prevents in vitro myofibrillar proteins degradation by μ-calpain.
abstract: Myofibrillar proteins degradation contributes to meat tenderisation during post-mortem ageing. Protein phosphorylation has been revealed to be associated with meat tenderness in recent years. This study was undertaken to determine the impact of myofibrillar proteins phosphorylation on the degradation susceptibility by μ-calpain. Myofibrillar proteins were first incubated with protein kinase A (PKA) or alkaline phosphatase (AP) to increase or decrease the phosphorylation level, following μ-calpain hydrolysis. Myosin heavy chain, actin, desmin and troponin T showed different levels of degradation in control, AP and PKA groups under different Ca2+concentrations. Generally, more degradation products were detected with the increase of Ca2+concentration. Compared to the control, the protein degradation was higher in AP-treated group and lower in PKA-treated group. This study shows that phosphorylation prevents proteolytic susceptibility of myofibrillar proteins to degradation by μ-calpain, indicating that protein phosphorylation plays an important role in meat tenderisation during post-mortem ageing.
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, PR China. Electronic address: lizheng1986114@163.com.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, PR China.
authors.forename: Xing
authors.initials: X
authors.lastname: Gao
authors.affiliation: College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, PR China.
authors.forename: Qingwu W
authors.initials: QW
authors.lastname: Shen
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, PR China.
authors.forename: Manting
authors.initials: M
authors.lastname: Du
authors.affiliation: Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing 100193, PR China. Electronic address: dequan_zhang0118@126.com.
authors.forename: Dequan
authors.initials: D
authors.lastname: Zhang
mesh_terms: D002154:Calpain / Q000378:metabolism*; D006801:Humans; D008460:Meat; D009124:Muscle Proteins / Q000378:metabolism*; D009210:Myofibrils / Q000378:metabolism*; D010766:Phosphorylation; D059748:Proteolysis
chemical_list: D009124:Muscle Proteins; D002154:Calpain; C449002:mu-calpain
keywords: Degradation; Myofibrillar proteins; Protein phosphorylation; μ-Calpain