Immunologic detection of a protein homologous to chicken progesterone receptor B subunit.
A monoclonal antibody described previously by us (Edwards, D. P., Weigel, N. L., Schrader, W. T., O'Malley, B. W., and McGuire, W. L. (1984) Biochemistry 23, 4427-4435) was used to study progesterone receptor B subunits of chick and hen oviduct. We find that the antibody does not recognize the form of receptor B able to bind [3H]progesterone in vitro. Rather, it reacts exclusively with a homologous protein of the same molecular weight, termed B antigen. The antigen is present in both immature estrogen-treated chicks and in egg-laying hens. This antigen is indistinguishable from the hormone-binding receptor species (termed receptor B) as shown by peptide mapping techniques using either Staphylococcus aureus V8 protease or trypsin. The B antigen and the hormone binder can be resolved by ion-exchange chromatography. Sedimentation velocity data show that the two proteins are present in distinct, separable cytosolic entities. The functional relationship between the two proteins has not been established.
Peleg
S
S
Schrader
W T
WT
Edwards
D P
DP
McGuire
W L
WL
O'Malley
B W
BW
D000367:Age Factors; D000818:Animals; D001345:Autoradiography; D002645:Chickens; D002848:Chromatography, DEAE-Cellulose; D003429:Cross Reactions; D003600:Cytosol / Q000032:analysis; D010450:Endopeptidases / Q000378:metabolism; D000939:Epitopes / Q000032:analysis; D005260:Female; D007122:Immunoelectrophoresis; D046911:Macromolecular Substances; D010057:Oviducts / Q000032:analysis; D011374:Progesterone / Q000378:metabolism; D011980:Receptors, Progesterone / Q000032:analysis* / Q000276:immunology; D012697:Serine Endopeptidases; D014461:Ultracentrifugation
D000939:Epitopes; D046911:Macromolecular Substances; D011980:Receptors, Progesterone; D011374:Progesterone; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase