Goldberg A L, Boches F S
Science. 1982 Feb 26;215(4536):1107-9. doi: 10.1126/science.7038874.
The rate of protein degradation in rabbit erythrocytes in normally very low. However, when cells were exposed to agents that oxidize cell proteins (nitrite or phenylhydrazine), the degradation of erythrocyte proteins to amino acids increased 7- to 33-fold. This effect was inhibited by the reducing agent methylene blue. Stimulation of proteolysis also occurred in cell extracts and resulted from the production of substrates (damaged proteins) rather than from activation of proteases. Inhibitors of glycolysis and of the soluble adenosine triphosphate-dependent proteolytic pathway decreased the protein degradation induced by nitrite, whereas inhibitors of lysosomal proteolysis had no effect. Thus, the adenosine triphosphate-dependent proteolytic system is present in mature red cells where it may help protect against the accumulation of proteins damaged by oxidation or other means.
正常情况下，兔红细胞中蛋白质的降解速率非常低。然而，当细胞暴露于能氧化细胞蛋白质的试剂（亚硝酸盐或苯肼）时，红细胞蛋白质降解为氨基酸的过程增加了7至33倍。这种效应被还原剂亚甲蓝抑制。细胞提取物中也发生了蛋白水解的刺激，这是由底物（受损蛋白质）的产生而非蛋白酶的激活导致的。糖酵解抑制剂和可溶性三磷酸腺苷依赖性蛋白水解途径抑制剂降低了亚硝酸盐诱导的蛋白质降解，而溶酶体蛋白水解抑制剂则没有效果。因此，三磷酸腺苷依赖性蛋白水解系统存在于成熟红细胞中，它可能有助于防止因氧化或其他方式受损的蛋白质积累。
