Cloning and characterization of cDNAs encoding 2,3,7,8-tetrachlorodibenzo-p-dioxin-inducible rabbit mRNAs for cytochrome P-450 isozymes 4 and 6.
Monoclonal antibodies toward rabbit liver cytochrome P-450 isozyme 6 (P-450 6) were used to identify several recombinant clones from a pBR322 cDNA library that express beta-lactamase-P-450 6 hybrid proteins. The nucleic acid sequence and predicted amino acid sequence of a rabbit P-450 6 cDNA shows a high degree of homology with rat P-450c and mouse P1-450. When used as a probe to rescreen the library, the P-450 6 cDNA hybridized to several heterologous classes of cDNAs. One such class was shown to encode P-450 4 by comparison of its predicted amino acid sequence to amino acid sequences of cysteine-containing tryptic peptides derived from P-450 4. DNA sequence analysis of a cDNA clone belonging to a third class demonstrated that it contained a 131-base-pair intervening sequencing when compared to the cDNA coding for P-450 6. This sequence corresponds in location to intron E of the rat P-450c gene. Blot-hybridization analysis demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) dramatically induced P-450 4 and 6 mRNAs, which differ in size. The sizes of these mRNAs differ from their analogs in the mouse as a result of divergence in the 3' untranslated portions of the mRNAs.
Okino
S T
ST
Quattrochi
L C
LC
Barnes
H J
HJ
Osanto
S
S
Griffin
K J
KJ
Johnson
E F
EF
Tukey
R H
RH
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000235:genetics*; D004247:DNA / Q000378:metabolism*; D004262:DNA Restriction Enzymes; D004147:Dioxins / Q000494:pharmacology*; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics*; D008099:Liver / Q000378:metabolism*; D051379:Mice; D010957:Plasmids; D000072317:Polychlorinated Dibenzodioxins / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics*; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D014158:Transcription, Genetic / Q000187:drug effects*
D004147:Dioxins; D007527:Isoenzymes; D000072317:Polychlorinated Dibenzodioxins; D012333:RNA, Messenger; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D004262:DNA Restriction Enzymes