Koshio O, Akanuma Y, Kasuga M
Institute for Diabetes Care and Research, Asahi Life Foundation, Tokyo, Japan.
Biochem J. 1988 Feb 15;250(1):95-101. doi: 10.1042/bj2500095.
H-35 rat hepatoma cells were labelled with [32P]orthophosphate and their insulin receptors isolated on wheat germ agglutinin (WGA)-agarose and anti-(insulin receptor) serum. The incubation of these cells with 10 mM-H2O2 for 10 min increased the phosphorylation of both the serine and tyrosine residues of the beta subunit of the insulin receptor. Next, insulin receptors were purified on WGA-agarose from control and H2O2-treated H-35 cells and the purified fractions incubated with [gamma-32P]ATP and Mn2+. Phosphorylation of the beta subunit of insulin receptors obtained from H2O2-treated cells was 150% of that of control cells. The kinase activity of the WGA-purified receptor preparation obtained from H2O2-treated cells, as measured by phosphorylation of src-related synthetic peptide, was increased about 4-fold over control cells. These data suggest that in intact cell systems, H2O2 may increase the insulin receptor kinase activity by inducing phosphorylation of the beta subunit of insulin receptor.
用[32P]正磷酸盐标记H-35大鼠肝癌细胞，并在麦胚凝集素（WGA）-琼脂糖和抗（胰岛素受体）血清上分离其胰岛素受体。将这些细胞与10 mM-H2O2孵育10分钟，增加了胰岛素受体β亚基丝氨酸和酪氨酸残基的磷酸化。接下来，从对照和H2O2处理的H-35细胞中在WGA-琼脂糖上纯化胰岛素受体，并将纯化的级分与[γ-32P]ATP和Mn2+一起孵育。从H2O2处理的细胞中获得的胰岛素受体β亚基的磷酸化是对照细胞的150%。通过src相关合成肽的磷酸化测量，从H2O2处理的细胞中获得的WGA纯化受体制剂的激酶活性比对照细胞增加了约4倍。这些数据表明，在完整细胞系统中，H2O2可能通过诱导胰岛素受体β亚基的磷酸化来增加胰岛素受体激酶活性。
