Transformation of the glucocorticoid receptor in rat liver cytosol by lysosomal enzymes

摘要: It has previously been shown that the glucocorticoid.receptor complex in liver cytosol undergoes limited proteolysis when incubated with trypsin or 1,000 to 10,000 x g sediment of homogenate. We now show incubation largest form dexamethasone*receptor complex, 6.1 nm an extract purified lysosomes from rat results formation two smaller glucocorticoid*receptor complexes Stokes radii 3.6 and 1.9 nm, respectively. No other intermediate forms steroid.receptor are found after lysosomal extract. The -+ + conversion is proportional amount added incubations occurs at a higher rate temperature raised. inhibited by addition gelatin but does not appear be any specific cathepsin inhibitors antipain, leupeptin, pepstatin pchloromercuribenzoate. suggested protease convert glucocorticoid *receptor forms, one which lacks capacity bind DNA. This mechanism may importance for regulation number reach binding sites on chromatin, inactivation breakdown receptor, both.