Enzymatic activities of P-450(11 beta)s expressed by two cDNAs in COS-7 cells.
Expression plasmids were constructed using two cDNA clones of P-450(11 beta), pcP-450-(11 beta)-2, and pcP-450(11 beta)-3 (Morohashi et al. (1987) J. Biochem. 102, 559-568 and Kirita et al. (1988) J. Biochem. 104, 683-686), and introduced into COS-7 cells by electroporation. The expression of P-450(11 beta) proteins and their localization in the mitochondria were demonstrated by immunoblotting, immunofluorescence microscopy, and immunoelectron microscopy. The enzymatic activities of the expressed P-450(11 beta)s were determined using deoxycorticosterone (DOC), deoxycortisol, and corticosterone as substrates. Though the activities of the two P-450(11 beta)s for 11-, 18-, and 19-hydroxylation of DOC were almost equal, the production of 18-hydroxycorticosterone and aldosterone from corticosterone by P-450(11 beta)-3 was greater than that by P-450(11 beta)-2.
Morohashi
K
K
Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka.
Nonaka
Y
Y
Kirita
S
S
Hatano
O
O
Takakusu
A
A
Okamoto
M
M
Omura
T
T
D000818:Animals; D002478:Cells, Cultured; D003345:Corticosterone / Q000378:metabolism; D003350:Cortodoxone / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis*; D003900:Desoxycorticosterone / Q000378:metabolism; D015870:Gene Expression; D000882:Haplorhini; D006900:Hydroxylation; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism* / Q000382:microbiology / Q000648:ultrastructure; D013252:Steroid 11-beta-Hydroxylase / Q000235:genetics* / Q000378:metabolism; D013250:Steroid Hydroxylases / Q000235:genetics*; D014162:Transfection
D003900:Desoxycorticosterone; D004247:DNA; D013250:Steroid Hydroxylases; D013252:Steroid 11-beta-Hydroxylase; D003345:Corticosterone; D003350:Cortodoxone