| First Author | Noshiro M | Year | 1986 |
| Journal | Arch Biochem Biophys | Volume | 244 |
| Issue | 2 | Pages | 857-64 |
| PubMed ID | 3753840 | Mgi Jnum | J:8187 |
| Mgi Id | MGI:56656 | Doi | 10.1016/0003-9861(86)90655-7 |
| Citation | Noshiro M, et al. (1986) Female-predominant expression of testosterone 16 alpha-hydroxylase (I-P-450(16)alpha) and its repression in strain 129/J. Arch Biochem Biophys 244(2):857-64 |
| abstractText | Using specific testosterone 16 alpha-hydroxylase activity as the basis for selection of fractions during purification, the cytochrome P-450 (I-P-450(16)alpha) has been isolated from livers of phenobarbital-treated 129/J female mice [K. Devore, N. Harada, and M. Negishi (1985) Biochemistry, 24, 5632-5637]. An antibody elicited in rabbits to I-P-450(16)alpha was used to determine the amount of hepatic microsomal 16 alpha-hydroxylase activity due to I-P-450(16)alpha in untreated females and males of the two mouse strains, 129/J and BALB/cJ. The activities inhibited were 0.03 and 0.3 nmol/min/mg protein in the 129/J and BALB/cJ females, respectively. No significant level of I-P-450(16)alpha-dependent activity was detected in the microsomes from males of either mouse strain. Immunoblotting of microsomal proteins with the antibody to I-P-450(16)alpha revealed approximately a 10-fold greater amount of a 54-kDa protein in the microsomes from BALB/cJ than from 129/J females (0.03 and 0.26 pmol/micrograms protein, respectively). A cDNA clone (R17) for phenobarbital-inducible rat cytochrome P-450 selected I-P-450(16)alpha mRNA of mice, indicating a high degree of homology between the mRNAs of mouse I-P-450(16)alpha and phenobarbital-inducible rat cytochrome P-450s. Northern and dot hybridization of total mouse liver poly(A)+ RNA with the R17 cDNA probe indicated that the specific content of the hybridizable mRNA was more than 10 times higher in BALB/cJ females than in males, and that the mRNA level in female 129/J mice was very similar to that of 129/J and BALB/cJ males. The repression of I-P-450(16)alpha in 129/J females was inherited as an autosomal recessive trait in 129/J and BALB/cJ pairs as indicated by the levels of mRNA in female F1 offspring and the I-P-450(16)alpha-dependent hydroxylase activity. Female and male mice of eight more inbred strains (AKR/J, DBA/2J, C57BL/6J, C3H/HeJ, NZB/J, A/J, CBA/CaJ, and P/J) were tested for levels of mRNA. The results showed that the levels of mRNA were always 5- to 10-fold greater in the females than in the corresponding males, although there was some variation in the mRNA content in the males from the different strains. 129/J females appear to be a genetic variant where the female-predominant expression of the mRNA is repressed. |
