stat3 is a direct Lef1 target gene. (A) Density plot from Lef1 ChIP-seq. Sequences from total input chromatin are on top and Lef1 ChIP are below, plotted on the UCSC genome assembly. A peak of Lef1 binding is observed at the stat3 promoter (arrow). (B) Genomic sequence upstream of stat3 transcription start site, identified by Lef1 ChIP-seq. Putative Lef/Tcf binding sites are in red, and mRNA sequence is in green. (C) Direct ChIP using Lef1 antibody with primers indicated in panel (B). Mean percent of total input chromatin by qPCR from 3 independent experiments is shown. Precipitation from wild-type 36 hpf chromatin is significantly enriched over chromatin from lef1 deletion mutant embryos. ChIP from a control genomic region without putative binding sites shows no enrichment. Error bars = s.d., *p < 0.05 by student's t-test. (D,E) stat3 expression is decreased 8 hours after ubiquitous expression of the constitutive repressor ΔTcf. Cross-sections through the hypothalamus are shown in (E). Both wild-type embryos (left) and siblings expressing hs:Δtcf (right) were heat-shocked at 28 hpf and processed for stat3 in situ hybridization at 36 hpf.