Role of the degradation process in the mitogenic effect of epidermal growth factor

摘要: Abstract The protease inhibitor leupeptin inhibits the degradation process of 125I-labeled epidermal growth factor (125I-EGF) by cultured bovine granulosa cells. At 80 μg/ml, inhibited appearance products 125I-EGF in medium 95% during 1 hr incubation and 90% 24 when cells were exposed to 5 ng per ml. In contrast, cultures either saturating (10 ng/ml) or nonsaturating (0.1 concentrations EGF presence (80 μg/ml) exhibited an increase DNA synthesis that was 70-80% alone. Cultures responded fibroblast with a logarithmic cell number and, over period 8 days, increased 10- 18-fold. Addition did not diminish rate cultures. leupeptin, accumulated within form precipitable antiserum against comigrated on isoelectric focusing native 125I-EGF. That full mitogenic response can be obtained despite 90-95% inhibition at mitogen suggests proteolytic given may involved induction proliferative response.