Erythroid-specific transcription of the chicken histone H5 gene is directed by a 3' enhancer

The expression of a variety of vertebrate genes is transcriptionally regulated through tissue-specific cellular enhancer elements. An erythroid-specific enhancer sequence has recently been identified 3' to (downstream of) the chicken adult beta-globin gene. Here we report the identification of a second erythroid-specific enhancer sequence, which is 3' to the chicken histone H5 gene. The similarity of these two enhancer elements, with respect both to function and location relative to the target gene, implies some functional conservation in their evolution and in the mechanism by which they affect erythroid gene transcription.