A PB-responsive element (PBRE) located at 2318 to -2155 of CYP2b2 (Tottier et al., Gere, 158, 263-268, 1995: Park et al, JBC. 271. 23725-23728. 1906) contains a bipartite NF-1 site. Deletion analysis indicated that the full full PB response is retained within 90 bp (2258 to -2169). which contain the NF-1 site. when three (opies of the deleted gragments were linked to a minimal CYP2C2 prmoter and activity was assayed by direcd injedtion into ratliver. Mutation of either of the bipartite binding sites red red binding and reduced, but did not eliminate, the PB induction. Mutation of the intervening sequence did not affect binding or I'H induction. Binding of NF- 1 to the site was confimed by competition for the binding by oligonurleotidos 'ontaining a consensus NF-1 site and by "supershift" gel assays with antisera for NF-1. Double mutations in the two NF-1 sites and presently being analysed. To analyze the sequmre flanking the NF'-1 site. 36 on eittier side were aruilyzed by linker scanning nnHagenesi-. Mut.itions to either side of \F 1 reduced PB iridlid ion. hui none of t he inu'al ions eliminated 'he p H i es pou se e.n' ire! v when three copies of t he mutated fragments fused to the CYP2Cl promoter were tested. No difference-, were observed in binding lo the Ni' 1 site or to other unidentified sites with ex 11 ado from con t roi and I'H- treated rats. 'I hese results indicate that multiple regulator1,' factors 'oritnbute ID I'H induction within the PBHK. Supported by Mil grant CMfMfiO.
|Original language||English (US)|
|State||Published - 1997|
ASJC Scopus subject areas
- Molecular Biology