Study design and ChIP enrichment at representative SREBP1-occupied promoters.
A) Overall scheme to identify targets of SREBP1, NFY, and SP1 in HepG2 cells and to investigate the regulation of SREBP1 targets under opposing nutrient conditions. B) SREBP1 targets were identified using ChIP-chip with promoter tiling arrays; three representative SREBP1-occupied promoters are shown. Smoothed log2 ChIP enrichment values of tiled DNA probes are represented by vertical bars. Upper plots represent ChIP enrichment with an SREBP1-specific antibody whereas lower plots represent ChIP enrichment with rabbit IgG used as a negative control. Array hybridizations of unenriched (input) DNA were used as a reference for calculating ChIP enrichment. Chromosomal positions are indicated on the x-axis. Gene structure is shown to scale below each plot with 5′-UTRs (black boxes), exons (grey boxes) and introns (black lines) indicated.