Iodination of the progesterone receptor from hen oviduct spares the DNA-binding domain.
The progesterone receptor from hen oviduct is isolated as a complex of two subunits, A and B. The A protein binds one molecule of progesterone and also binds to DNA with high affinity. The native A protein can be labeled with iodine with no loss of DNA-binding activity. Limited Staphylococcus aureus V8 protease digestion of the labeled preparation results in a number of DNA-binding and non-DNA-binding fragments of the receptor. The progesterone-binding domain contains iodine label. However, two low-molecular-weight DNA-binding fragments do not contain iodine label, indicating a lack of susceptible tyrosine residues near the DNA-binding site of the native receptor. The labeled receptor and its fragments will facilitate studies of the isolated DNA-binding and progesterone-binding domains of the hen A protein as well as of the activity of the native receptor in the presence and absence of hormone.
D000818:Animals; D002645:Chickens; D004247:DNA / Q000493:pharmacokinetics*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D007457:Iodine Radioisotopes / Q000378:metabolism; D008970:Molecular Weight; D010057:Oviducts; D011980:Receptors, Progesterone / Q000378:metabolism*; D012697:Serine Endopeptidases / Q000378:metabolism
D004268:DNA-Binding Proteins; D007457:Iodine Radioisotopes; D011980:Receptors, Progesterone; D004247:DNA; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase