Complementary DNA cloning of cytochrome P-450s related to XXXX from the complementary DNA library of female @entity35 livers. Predicted primary structures for @entity13234 , PB-1, and PB-1-related protein with a bizarre replacement block and their mode of transcriptional expression.

@entity13233 @entity377 @entity11042 @entity35 @entity13234 @entity1446
Three kinds of cDNA clones were isolated from a cDNA library synthesized from female @entity35 liver mRNA by cross-hybridization with the @entity11042 ) cDNA as a probe and sequenced. One clone appears to be the previously isolated @entity13234 cDNA clone with an additional 5'-untranslated and coding sequence which are lacking in the previously reported clone (Gonzalez, F. J., Kimura, S., Song, B.-J., Pastewka, J., Gelboin, H. V., and Hardwick, J. P. (1986) J. Biol. Chem. 261, 10667-10672), though several @entity377 differences were seen. Another one is for @entity13233 mRNA previously isolated, and the last has an almost identical @entity377 sequence to @entity13233 (the same report cited above) except for one region of 159 base pairs where the sequence homology between the two is abruptly broken down. This nonhomologous region appears to correspond exactly to the entire eighth exon, estimated by comparison with the gene structure of the related P-450 ( @entity11042 ). This replacement in @entity13233 (ps) causes a frameshift in the open reading frame, resulting in the generation of a truncated form of P-450 with a strange replacement block and lacking the @entity1446 -binding region. This observation suggests that the mRNA whose cDNA was cloned here was produced from a recombinant gene generated by gene conversion or from alternative splicing of a cryptic exon. Sex- and age-dependent expression of the mRNAs investigated by dot blot analysis revealed that normal- and pseudo-type PB-1 mRNA were expressed in both male and female @entity35 livers, though their age-dependent expression was different in male and female animals. In addition, both the mRNAs were specifically expressed in the female brain of 8 weeks, whereas practically no expression was observed in kidney and lung of both sexes.
