%0 Journal Article %T Spatial organization of the chicken beta-globin gene domain in erythroid cells of embryonic and adult lineages %A Sergey V Ulianov %A Alexey A Gavrilov %A Sergey V Razin %J Epigenetics & Chromatin %D 2012 %I BioMed Central %R 10.1186/1756-8935-5-16 %X Using chromosome conformation capture (3C), we have compared the spatial configuration of the ¦Â-globin gene domain in chicken red blood cells (RBCs) expressing embryonic (3-day-old RBCs) and adult (9-day-old RBCs) ¦Â-globin genes. In contrast to observations made in the mouse model, we found that in the chicken, the early embryonic ¦Â-globin gene, ¦¥, did not interact with the locus control region in RBCs of embryonic lineage (3-day RBCs), where this gene is actively transcribed. In contrast to the mouse model, a strong interaction of the promoter of another embryonic ¦Â-globin gene, ¦Ñ, with the promoter of the adult ¦Â-globin gene, ¦ÂA, was observed in RBCs from both 3-day and 9-day chicken embryos. Finally, we have demonstrated that insulators flanking the chicken ¦Â-globin gene domain from the upstream and from the downstream interact with each other, which places the area characterized by lineage-specific sensitivity to DNase I in a separate chromatin loop.Taken together, our results strongly support the ACH model but show that within a domain of tissue-specific genes, the active status of a promoter does not necessarily correlate with the recruitment of this promoter to the ACH.The domain of chicken beta-globin genes is located on chromosome 1 and has a length of approximately 33 kb. It includes a cluster of four beta-globin genes: ¦Ñ (HBG1), ¦ÂH (HBE1), ¦ÂA (HBG2) and ¦¥ (HBE) and several distant regulatory regions, which are marked with sites of hypersensitivity to DNase I (HS) and are necessary for the regulation of transcription, replication and chromatin status of the domain [1,2]. The locus control region of the domain (LCR) is located upstream of the embryonic ¦Â-globin gene ¦Ñ and is composed of three blocks co-localizing with the erythroid cell-specific HSs 1 to 3 [3,4]. A constitutive HS4 located upstream of the LCR marks the position of the well-studied CTCF-dependent (CTCF ©\ D£¿D£¿D£¿TC-binding protein factor) insulator [5-9]. The CTCF-dependent enhancer-blocking e %K ¦Â-globin genes %K Active chromatin hub %K Insulator %K Chicken RBCs %U http://www.epigeneticsandchromatin.com/content/5/1/16