FIGURE 7.

CHOP binds to C/EBPα sites in diverse promoters. A, a schematic of the Ppara promoter shows overlap between the ChIP-defined CHOP-binding region (gray box) and a C/EBPα-binding region defined by ChIP-seq (black box) (40). Ex 1, exon 1. B, expression of C/EBPα and the LIP and LAP (liver-enriched transcriptional activating protein) forms of C/EBPβ following 8 h of treatment with TM as determined by immunoblotting. The asterisk indicates a nonspecific band showing equal loading. For C/EBPα, only the long form of the protein is shown; the 30-kDa short form could not be unambiguously identified. C, promoter/enhancer regions from the indicated genes were assessed for C/EBPα binding by ChIP (IP). For Ppara and Gadd34, primers spanning CHOP-binding regions were used for qPCR. For Fga and Eif2s2, primers covered regions identified by ChIP-seq. Association with an irrelevant genomic sequence (irrel) is also shown. ChIP used anti-C/EBPα or control antibody in animals treated for 8 h with vehicle or 1 mg/kg TM (n = 4). D, binding of C/EBPβ (using an antibody that recognizes both LAP and LIP forms of the protein) to the CHOP-binding sites of the Ppara and Srebf1 promoters or to an irrelevant genomic sequence was assessed by ChIP after 8 h of TM challenge.