Fig. 4. In vivo association of SEU protein with AG 3' enhancer. (A) Diagram of the AG second intron, which coincides with an 3 kb HindIII fragment (Bao et al., 2004; Busch et al., 1999; Deyholos and Sieburth, 2000). Numbers indicate the nucleotide sequence, with the 5' HindIII site designated as 1. The location of LFY/WUS-binding sites (back circles), CArG boxes (diamonds), and BLR-binding sites (triangles) is indicated. The two `redundant' enhancers defined by KB14 (5' enhancer) and KB18 (3' enhancer) reporter lines (Busch et al., 1999), as well as the position of the AG-5 and AG-3 PCR products, are shown. The 900 bp AG fragment in the pAG3'I::LUC reporter is indicated. Drawing is not to scale. (B) Association of SEU with the AG 3' enhancer revealed by ChIP with an anti-SEU antibody. AG-5 and AG-3 are PCR products detecting immunoprecipitated wild-type and seu-3 chromatin, respectively. The control E1F4P primer amplifies a non-regulatory target of LUG/SEU. `No Ab' and `SEU Ab' correspond to chromatin treated without or with anti-SEU antibodies, respectively.