CHROMATIN STRUCTURE AND THE EXPRESSION OF GLOBIN-ENCODING GENES

The developmental regulation of globin gene expression in the chicken has been studied. All of the genes are regulated by a small number of general erythroid factors. In addition, expression of individual membe rs of the family must be controlled in a lineage (stage)-specific mann er. In some cases, the relevant factors may be stage specific, but in others they are not confined to one stage, but exert their control thr ough developmentally regulated changes in their abundance within the n ucleus. Chromatin structural elements, such as locus control regions a nd insulators, are also involved in control of eukaryotic gene express ion. Because so much is understood about regulation of individual gene s, the globin family has proven valuable in investigating control of t ranscription at the level of chromatin structure.