Fig. 7.
A Stat5-binding site is present in the RARE within the RARβ promoter.
(A) Sequence of the RARE within the RARβ promoter (−55 to −33).21 The two 6-bp direct repeats making up the DR5 element are in bold. (B) Nuclear extracts from BaF3 cells transfected with a Stat5 expression vector were used in an EMSA or an EMSA supershift with the indicated labeled probes and antibody. The Stat5 oligo harbors a consensus Stat5-binding sequence (see “Materials and methods” for this sequence). (C) The βRAREm4 oligo, which harbors mutations within the 6-bp direct repeats while retaining the consensus Stat-binding site (see “Materials and methods” for the exact sequence) served as a probe in EMSAs using BaF3 nuclear extracts and different Stat antibodies as indicated. (D) The labeled Stat5 oligo served as a probe in EMSAs using BaF3 nuclear extracts. Competition reactions were performed with the addition of an excess of different cold oligos as indicated.