Article thumbnail
Location of Repository

Initiation of DNA replication at the human β-globin 3′ enhancer

By Alla Buzina, Mirit I. Aladjem, John L. Kolman, Geoffrey M. Wahl and James Ellis


The origin of DNA replication in the human β-globin gene contains an initiation region (IR) and two flanking auxiliary elements. Two replicator modules are located within the upstream auxiliary sequence and the IR core, but the functional sequences in the downstream auxiliary element are unknown. Here, we use a combination of benzoylated-naphthoylated DEAE (BND) cellulose purification and nascent strand abundance assays to show that replication initiation occurs at the β-globin 3′ enhancer on human chromosome 11 in the Hu11 hybrid murine erythroleukemia (MEL) cell line. To examine replicator function, 3′ enhancer fragments were inserted into an ectopic site in MEL cells via an optimized FRT/EGFP-FLP integration system. These experiments demonstrate that the 1.6 kb downstream auxiliary element is a third replicator module called bGRep-E in erythroid cells. The minimal 260 bp 3′ enhancer is required but not sufficient to initiate efficient replication, suggesting cooperation with adjacent sequences. The minimal 3′ enhancer also cooperates with elements in an expressing HS3β/γ-globin construct to initiate replication. These data indicate that the β-globin replicator has multiple initiation sites in three closely spaced replicator modules. We conclude that a mammalian enhancer can cooperate with adjacent sequences to create an efficient replicator module

Topics: Article
Publisher: Oxford University Press
Year: 2005
DOI identifier: 10.1093/nar/gki747
OAI identifier:
Provided by: PubMed Central

Suggested articles


  1. (1987). A 30 enhancer contributes to the stage-specific expression of the human beta-globin gene.
  2. and Aladjem,M.I.(2004) Thehumanbeta-globinreplication initiationregion consists of two modular independent replicators.
  3. and de Laat,W.(2003) The beta-globinnuclear compartment in development and erythroid differentiation.
  4. Antoniou,M.andGrosveld,F.(1990)beta-globindominantcontrolregion interacts differently with distal and proximal promoter elements.
  5. Cimbora,D.M., Brody,L.L.,Epner,E.M.,Groudine,M.andWahl,G.M.(2002)Replication initiation patterns in the beta-globin loci of totipotent and differentiated murine cells: evidence for multiple initiation regions.
  6. (2004). Defined sequence modules and an architectural element cooperate to promote initiation at an ectopic mammalian chromosomal replication origin.
  7. (1990). Definition of the minimal requirements within the human beta-globin gene and the dominant control region for high level expression.
  8. (2001). Developmental regulation of DNA replication timing at the human beta globin locus.
  9. (1998). Discrete start sites for DNA synthesis in the yeast ARS1 origin.
  10. (1999). Efficient and reliable transfection of mouseerythroleukemiacellsusingcationiclipids.BloodCellsMol.Dis.,
  11. Fournier,R.E., Wahl,G.M.andEpner,E.M.(1995)Participationofthehumanbeta-globin locus control region in initiation of DNA replication.
  12. (1998). Genetic dissection of a mammalian replicator in the human beta-globin locus.
  13. Imam,A.M., Strouboulis,J.,deLaat,W.andGrosveld,F.G.(2004)Multipleinteractions between regulatory regions are required to stabilize an active chromatin hub.
  14. (2000). In vivo identification of lymphocyte subsets exhibiting transcriptionally active NF-kappaB/Rel complexes.
  15. (1990). Induction by HMBA and DMSO of genes introduced into mouse erythroleukemia and other cell lines by transient transfection.
  16. Kitsberg,D.,Selig,S.,Keshet,I.andCedar,H.(1993)Replicationstructure of the human beta-globin gene domain.
  17. (2003). LCR-regulated transgene expression levels depend on the Oct-1 site in the AT-rich region of beta-globin intron-2.
  18. (2000). Locus control region activity by 50HS3 requires a functional interaction with beta-globin gene regulatory elements: expression of novel beta/gamma-globin hybrid transgenes.
  19. (2000). Long-distance control of origin choice and replication timing in the human beta-globin locus are independent of the locus control region.
  20. (2004). Modular structure of the human lamin B2 replicator.
  21. (2003). Multiple functional elements comprise a Mammalian chromosomal replicator.
  22. (1997). Mutation of gene-proximal regulatory elements disrupts human epsilon-, gamma-, and beta-globin expression in yeast artificial chromosome transgenic mice.
  23. (1995). ORC and Cdc6p interact and determine the frequency of initiation of DNA replication in the genome.
  24. Pasceri,P.,Pannell,D.,Wu,X.andEllis,J.(1998)Fullactivityfromhuman beta-globin locus control region transgenes requires 50HS1, distal beta-globin promoter, and 30 beta-globin sequences.
  25. (1987). Position-independent, high-level expression of the human beta-globin gene in transgenic mice.
  26. (1991). Recombinase-mediated gene activation and site-specific integration in mammalian cells.
  27. (1988). Replication program of active and inactive multigene families in mammalian cells.
  28. (2004). Specification of a DNA replication origin by a transcription complex.
  29. (1988). The human beta-globin gene 30 enhancer contains multiple binding sites for an erythroid-specific protein.
  30. (1987). The human beta-globin gene contains a downstream developmental specific enhancer.
  31. (1988). The human beta-globin gene contains multiple regulatory regions: identification of one promoter and two downstream enhancers.
  32. (1999). The organization of replication and transcription.
  33. (2004). Transcriptionfactorbindingandinducedtranscriptionalterchromosomal c-myc replicator activity.
  34. (1987). Two 30 sequences direct adult erythroid-specific expression of human beta-globin genes in transgenic mice.
  35. (2000). Use of green fluorescent protein/Flp recombinasefusionproteinandflowcytometricsortingtoenrichforcells undergoing Flp-mediated recombination.
  36. (1969). Vegetative lambda DNA. IV. Fractionation of replicating lambda

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.