Figure 3

Egr2 binds NAB promoters in myelinating sciatic nerve. Formaldehyde-crosslinked chromatin from sciatic nerves of rats at P10 was immunoprecipitated with an antibody for Egr2 (filled bars) or purified control IgG (open bars). Percentage recovery relative to input DNA was determined by quantitative PCR with the same primers used in Figure 2. The horizontal lines above the promoter diagrams indicate the positions of the amplicons derived from the primer sets used for ChIP analysis. Binding at the transcriptionally silent IMG2A locus was analyzed as a negative control. The data are representative of at least two independent experiments; average fold enrichment for Egr2 binding (relative to control IgG immunoprecipitation) to the Nab2 promoter in four independent experiments was 51-fold (P = 0.016). Inset: Immunoblot analysis with the same antibody used in the ChIP assay was used to detect Egr2 (~70 kD) in rat sciatic nerve lysates at P5 and P15. Three amounts of the P15 lysate (in increasing 2-fold amounts in lanes 2–4) were loaded to facilitate comparison with the expression level at P5. The blot was reprobed with a β-actin antibody as a normalization control (bottom panel).