Differential induction and tissue-specific expression of closely related members of the phenobarbital-inducible rabbit cytochrome P-450 gene family.
We have examined the tissue-specific expression of three rabbit genes that are closely related members of a subfamily of the phenobarbital-inducible cytochrome P-450 gene family. Analysis of the levels of mRNA in liver revealed that (a) cytochrome P-450PBc1 mRNA was not detectable in livers from control animals but was present in livers from animals treated with phenobarbital, (b) cytochrome P-450PBc2 was present in control tissue and was increased by about 3-fold 24 h after phenobarbital treatment, and (c) the levels of cytochrome P-450PBc3 mRNA was the same in livers from control and treated animals. In the kidney, only P-450PBc2 mRNA was detected at a level 15% of that in the liver, and the levels increased about 3-fold after phenobarbital treatment. None of the mRNAs was detected in lung tissue. Multiple species of RNA were observed that hybridized to probes for cytochrome P-450PBc1 and P-450PBc2 cDNAs by Northern blot analysis ranging in size from 2300 to 4000 nucleotides. Differential sites for polyadenylation probably cause the heterogeneity in size. A single species of RNA of 2200 nucleotides that hybridized to cytochrome P-450PBc3 cDNA probes was observed. These data demonstrate that three closely related cytochrome P-450 genes are differentially responsive to phenobarbital treatment and that they exhibit different tissue-specific patterns of expression.
D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000235:genetics*; D004247:DNA / Q000032:analysis; D004790:Enzyme Induction; D005786:Gene Expression Regulation; D007527:Isoenzymes / Q000096:biosynthesis*; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D008297:Male; D009693:Nucleic Acid Hybridization; D010634:Phenobarbital / Q000494:pharmacology; D012313:RNA / Q000032:analysis; D011817:Rabbits; D013997:Time Factors; D014018:Tissue Distribution
D007527:Isoenzymes; D012313:RNA; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D010634:Phenobarbital