1. Opening Chromatin Molecular Cell
Stavros Lomvardas, Dimitris Thanos 
Molecular Cell 
Volume 9, Issue 2, Pages (February 2002)
DOI: /S (02)00463-X

2. Figure 1
A Model Depicting Developmental Regulation of Transcription of the Serum Albumin Gene
The albumin gene enhancer is embedded in a condensed chromatin environment at very early developmental stages. Upon gastrulation and formation of the endoderm, the transcription factors HNF3 and GATA-4 bind the enhancer. This induces local chromatin opening and reorganization of the enhancer DNA into three positioned nucleosomes. Chromatin opening in the albumin enhancer does not occur in the ectoderm and mesoderm due to the absence of HNF3 and GATA-4 expression in these layers. Next, HNF3 and GATA-4 help another molecule of HNF3, C/EBPβ, and NF1 to bind to their sites on enhancer DNA later in development. The albumin enhanceosome can now activate transcription by targeting chromatin-modifying and -remodeling machines to the albumin promoter.
Molecular Cell 2002 9, DOI: ( /S (02)00463-X)