A novel cytochrome P450 3A isoenzyme in rat intestinal microsomes.
PCR with several pairs of primers facilitates screening for new isoenzymes among highly homologous cytochrome P450s (CYPs). Combinations of two pairs of primers, which amplify N- and C-terminal coding sequences of either CYP3A1/CYP3A23 or CYP3A2 detected the presence of a previously unrecognized CYP3A in enterocyte microsomes isolated from rats. PCR, Northern blot, and immunoblotting with specific antibodies indicated that this isoenzyme is clearly distinguishable from CYP3A1, 3A23 or 3A2. Sequencing of a 285 bp coding fragment of this gene revealed 97% similarity with rat olfactory CYP3A9 (P450olf3).
Gushchin
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GV
Department of Pharmacology, College of Medicine, Ohio State University, Columbus 43210, USA. ghennady.gushchin@vtmednet.org
Gushchin
M I
MI
Gerber
N
N
Boyd
R T
RT
D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases; D001483:Base Sequence; D015152:Blotting, Northern; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000302:isolation & purification*; D018076:DNA, Complementary / Q000302:isolation & purification; D007413:Intestinal Mucosa / Q000166:cytology / Q000201:enzymology*; D007527:Isoenzymes / Q000235:genetics / Q000302:isolation & purification; D008297:Male; D008861:Microsomes / Q000201:enzymology*; D008969:Molecular Sequence Data; D010089:Oxidoreductases, N-Demethylating / Q000235:genetics / Q000302:isolation & purification*; D010446:Peptide Fragments / Q000235:genetics / Q000302:isolation & purification; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D013250:Steroid Hydroxylases / Q000235:genetics / Q000302:isolation & purification
D018076:DNA, Complementary; D007527:Isoenzymes; D010446:Peptide Fragments; D003577:Cytochrome P-450 Enzyme System; D013250:Steroid Hydroxylases; D001189:Aryl Hydrocarbon Hydroxylases; C465138:Cyp3a23-3a1 protein, rat; D051544:Cytochrome P-450 CYP3A; C022657:steroid hormone 6-beta-hydroxylase; D010089:Oxidoreductases, N-Demethylating