An insulator element and condensed chromatin region separate the chicken β-globin locus from an independently regulated erythroid-specific folate receptor gene

Authors

Marie-Noelle Prioleau, Laboratoire de Genetique Moleculaire, CNRS URA 1302, 46 rue d'Ulm, 75230 Paris Cedex 05, France
Pascale Nony, Laboratoire de Therapie Genique, Bitiment Jean Monnet-Hatel Dieu 30, boulevard Jean Monnet, 44035 Nantes Cedex 1, France
Melanie A. Simpson, University of Nebraska - LincolnFollow
Gary FelsenfeldFollow

Document Type

Article

Date of this Version

October 1999

Comments

Published in The EMBO Journal Vo1.18 No.14 pp.4035-4048, 1999. Copyright Oxford University Press. Used by permission.

Abstract

We have identified a folate receptor gene upstream of the chicken β-globin locus and separated from it by a 16 kbp region of silent chromatin. We find that this receptor is expressed only at a stage of erythroid differentiation (CFU-E) preceding the activation of β-globin genes, consistent with the role of folate receptors in proliferation. This discovery raises the question of how these two loci are regulated during erythropoiesis. Our data suggest that the folate receptor gene and the β-globin locus are regulated independently. We show that a 3.3 kbp DNA region upstream of the folate receptor gene is sufficient to induce strong expression of a transgene in CFU-E stage cells. We also find that the region between the β-globin locus and the folate receptor gene is fully methylated and condensed at this stage of differentiation. Its 3' boundary coincides with the 5' β-globin insulator. We speculate that the 5' β-globin boundary element might be important for the proper regulation of two adjacent domains activated at two different stages during differentiation.