FIG. 7.

Comparison of chromatin structures and gene activation pathways at the hCD79b/GH locus in pituitary tissue, placenta tissue, and B cells. The hCD79b/GH locus is diagrammed with the set of DNase I HS present in each tissue. Transcriptional activities are denoted by angled arrows at the indicated promoters. The “bystander” transcription of CD79b in the pituitary gland is indicated. Regions of H3 and H4 hyperacetylation are indicated by the shaded ovals below the diagrams. Proposed pathways of gene activation are indicated as long-range “spreading” (pituitary), “looping” (placenta), or “local” (B cell).