Key Laboratory of Meat Processing and Quality Control, MOE, Key Laboratory of Meat Processing, MOA, Jiangsu Synergetic Innovation Center of Meat Processing and Quality Control, Nanjing Agricultural University, Nanjing 210095, China; College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
Department of Animal Science, Iowa State University, Ames 50011, USA.
Food Chem. 2019 Mar 1;275:77-84. doi: 10.1016/j.foodchem.2018.09.104. Epub 2018 Sep 18.
The aim of this study was to investigate the dual effect of the nitric oxide donor NOR-3 and calpastatin on µ-calpain activity, autolysis, and proteolytic ability. µ-Calpain and calpastatin were purified and allocated to the following five treatments: µ-calpain, µ-calpain + calpastatin, µ-calpain + NOR-3, µ-calpain + calpastatin + NOR-3, and µ-calpain + NOR-3 + calpastatin. µ-Calpain autolysis and the activity against purified myofibrils was initiated by addition of calcium. Results showed that NOR-3 could induce µ-calpain S-nitrosylation and effectively block the activity via the inhibition of µ-calpain autolysis. Calpastatin inhibited µ-calpain activity in a dose-dependent manner. The combined treatment of NOR-3 and calpastatin exerted a further inhibitory effect on µ-calpain activity, autolysis and proteolysis which was affected by the addition order of NOR-3 and calpastatin. Our data suggest that S-nitrosylation may play a regulatory role in mediating µ-calpain activity in the presence of calpastatin.
本研究旨在探讨一氧化氮供体 NOR-3 和钙蛋白酶抑制剂对 μ-钙蛋白酶活性、自解和蛋白水解能力的双重影响。μ-钙蛋白酶和钙蛋白酶抑制剂被纯化，并分配到以下五种处理方式中：μ-钙蛋白酶、μ-钙蛋白酶+钙蛋白酶抑制剂、μ-钙蛋白酶+NOR-3、μ-钙蛋白酶+钙蛋白酶抑制剂+NOR-3 和 μ-钙蛋白酶+NOR-3+钙蛋白酶抑制剂。μ-钙蛋白酶的自解和对纯化肌原纤维的活性是通过添加钙离子引发的。结果表明，NOR-3 可诱导 μ-钙蛋白酶 S-亚硝基化，并通过抑制 μ-钙蛋白酶自解来有效阻断其活性。钙蛋白酶抑制剂呈剂量依赖性抑制 μ-钙蛋白酶活性。NOR-3 和钙蛋白酶抑制剂的联合处理对 μ-钙蛋白酶活性、自解和蛋白水解的抑制作用进一步增强，且 NOR-3 和钙蛋白酶抑制剂的添加顺序对其有影响。我们的数据表明，在钙蛋白酶抑制剂存在的情况下，S-亚硝基化可能在调节 μ-钙蛋白酶活性方面发挥调节作用。
