Intergenic transcription and transinduction of the human β-globin locus

Abstract
We have identified novel nuclear transcripts in the human β-globin locus using nuclear run-on analysis in erythroid cell lines and in situ hybridization analysis of erythroid tissue. These transcripts extend across the LCR and intergenic regions but are undetectable in nonerythroid cells. Surprisingly, transient transfection of a β-globin gene (ε, γ, or β) induces transcription of the LCR and intergenic regions from the chromosomal β-globin locus in nonerythroid cell lines. The β-globin genes themselves, however, remain transcriptionally silent. Induction is dependent on transcription of the globin gene in the transfected plasmid but does not require protein expression. Using in situ hybridization analysis, we show that the plasmid colocalizes with the endogenous β-globin locus providing insight into the mechanism of transinduction.