Reduced beta-Globin Gene Expression in Adult Mice Containing Deletions of Locus Control Region 5' HS-2 or 5' HS-3a

A stable transfection assay was used to test the mechanism by which embryonic globin gene transcription is stimulated in adult erythroid cells exposed to butyric acid and its analogs. To test the appropriate expression and inducibility of chicken globin genes in murine erythroleukemia (MEL) cells, an adult chicken beta-globin gene construct was stably transfected. The chicken beta-globin gene was found to be coregulated with the endogenous adult mouse alpha-globin gene following induction of erythroid differentiation of the transfected MEL cells by incubation with either 2% dimethyl sulfoxide (DMSO) or 1 mM sodium butyrate (NaB). In contrast, a stably transfected embryonic chicken beta-type globin gene, rho, was downregulated during DMSO-induced MEL cell differentiation. However, incubation with NaB, which induces MEL cell differentiation, or alpha-amino butyrate, which does not induce differentiation of MEL cells, resulted in markedly increased levels of transcription from the stably transfected rho gene. Analysis of histone modification showed that induction of rho gene expression was not correlated with increased bulk histone acetylation. A region of 5'-flanking sequence extending from -569 to -725 bp upstream of the rho gene cap site was found to be required for both downregulation of rho gene expression during DMSO-induced differentiation and upregulation by treatment with NaB or alpha-amino butyrate. These data are support for a novel mechanism by which butyrate compounds can alter cellular gene expression through specific DNA sequences. The results reported here are also evidence that 5'-flanking sequences are involved in the suppression of embryonic globin gene expression in terminally differentiated adult erythroid cells.

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Synergistic regulation of human beta-globin gene switching by locus control region elements HS3 and HS4.

Genes & Development ◽

10.1101/gad.9.24.3083 ◽

1995 ◽

Vol 9 (24) ◽

pp. 3083-3096 ◽

Cited By ~ 142

Author(s):

J Bungert ◽

U Dave ◽

K C Lim ◽

K H Lieuw ◽

J A Shavit ◽

...

Keyword(s):

Control Region ◽

Globin Gene ◽

Locus Control Region ◽

Beta Globin ◽

Beta Globin Gene ◽

Synergistic Regulation ◽

Gene Switching

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A novel deletion of approximately 27 kb including the beta-globin gene and the locus control region 3'HS-1 regulatory sequence: beta zero- thalassemia or hereditary persistence of fetal hemoglobin?

Blood ◽

10.1182/blood.v83.3.822.822 ◽

1994 ◽

Vol 83 (3) ◽

pp. 822-827 ◽

Cited By ~ 17

Author(s):

AJ Dimovski ◽

V Divoky ◽

AD Adekile ◽

E Baysal ◽

JB Wilson ◽

...

Keyword(s):

Control Region ◽

Globin Gene ◽

Fetal Hemoglobin ◽

Locus Control Region ◽

Regulatory Sequence ◽

Beta Globin ◽

Gamma Chain ◽

Beta Globin Gene ◽

Gamma Globin

Abstract A novel deletion of approximately 27 kb with the 5′ breakpoint 1.5 to 2.2 kb upstream of the beta-globin gene, and the 3′ breakpoint approximately 24 kb downstream of the beta-globin gene, has been found in five members of two families from Southeast Asia (Vietnam and Cambodia). Six members of another family from China, previously reported from our laboratory, have also been shown to carry this deletion. The patients presented with mild hypochromia and microcytosis, a hemoglobin (Hb) A2 level of approximately 4.0%, and a markedly increased, heterocellularly distributed, Hb F level (14.0 to 26.0%). In vitro globin-chain synthesis showed a mild imbalance with appreciable gamma-chain compensation (alpha/beta + gamma ratio of 1.46). The 3′ end of this deletion includes the 3′HS-1, and we hypothesize that removal of this region results in the loss of its gamma-globin gene-silencing effect, which causes a markedly elevated Hb F level with a modest increase in Hb A2 levels, unlike the situation in other deletional beta zero-thalassemias. The possible influence of particular sequence variations in the locus control region 5′HS-2 and the G gamma promoter, present on the chromosome with this deletion, on the overall gamma-globin gene should also be considered.

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Deletions within the Mouse β-Globin Locus Control Region Preferentially Reduce βmin Globin Gene Expression

Genomics ◽

10.1006/geno.1999.6104 ◽

2000 ◽

Vol 63 (3) ◽

pp. 417-424 ◽

Cited By ~ 9

Author(s):

Raouf Alami ◽

M.A. Bender ◽

Yong-Qing Feng ◽

Steven N. Fiering ◽

Bruce A. Hug ◽

...

Keyword(s):

Gene Expression ◽

Control Region ◽

Globin Gene ◽

Locus Control Region ◽

Globin Gene Expression

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Direct interaction of NF-E2 with hypersensitive site 2 of the β-globin locus control region in living cells

Blood ◽

10.1182/blood.v96.1.334.013k17_334_339 ◽

2000 ◽

Vol 96 (1) ◽

pp. 334-339 ◽

Cited By ~ 4

Author(s):

E. Camilla Forsberg ◽

Karen M. Downs ◽

Emery H. Bresnick

Keyword(s):

Gene Expression ◽

Control Region ◽

Globin Gene ◽

Locus Control Region ◽

Erythroid Cell ◽

Hypersensitive Site ◽

Intact Cells ◽

Erythroleukemia Cells ◽

Murine Erythroleukemia ◽

Globin Gene Expression

The human β-globin locus control region (LCR) confers high-level, tissue-specific expression to the β-globin genes. Tandem Maf recognition elements (MAREs) within the hypersensitive site 2 (HS2) subregion of the LCR are important for the strong enhancer activity of the LCR. Multiple proteins are capable of interacting with these sites in vitro, including the erythroid cell- and megakaryocyte-specific transcription factor, NF-E2. The importance of NF-E2 for β-globin gene expression is evident in murine erythroleukemia cells lacking the p45 subunit of NF-E2. These CB3 cells have a severe defect in - and β-globin gene transcription, which can be restored by expression of NF-E2. However, mice nullizygous for p45 express nearly normal levels of β-globin. Thus, either a redundant factor(s) exists in mice that can functionally replace NF-E2, or NF-E2 does not function through the LCR to regulate β-globin gene expression. To address this issue, we asked whether NF-E2 binds directly to the tandem MAREs of HS2 in intact cells. Using a chromatin immunoprecipitation assay, we provide evidence for NF-E2 binding directly and specifically to HS2 in living erythroleukemia cells and in mouse fetal liver. The specific immunoisolation of HS2 sequences was dependent on the presence of p45 and on intact MAREs within HS2. These results support a direct role for NF-E2 in the regulation of β-globin gene expression through activation of the LCR.

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Antagonistic Regulation of β-Globin Gene Expression by Helix-Loop-Helix Proteins USF and TFII-I

Molecular and Cellular Biology ◽

10.1128/mcb.01770-05 ◽

2006 ◽

Vol 26 (18) ◽

pp. 6832-6843 ◽

Cited By ~ 30

Author(s):

Valerie J. Crusselle-Davis ◽

Karen F. Vieira ◽

Zhuo Zhou ◽

Archana Anantharaman ◽

Jörg Bungert

Keyword(s):

Gene Expression ◽

Rna Polymerase Ii ◽

Control Region ◽

Adult Stage ◽

Globin Gene ◽

Locus Control Region ◽

Erythroid Cell ◽

Erythroid Cells ◽

Globin Gene Expression ◽

In Erythroid Cells

ABSTRACT The human β-globin genes are expressed in a developmental stage-specific manner in erythroid cells. Gene-proximal cis-regulatory DNA elements and interacting proteins restrict the expression of the genes to the embryonic, fetal, or adult stage of erythropoiesis. In addition, the relative order of the genes with respect to the locus control region contributes to the temporal regulation of the genes. We have previously shown that transcription factors TFII-I and USF interact with the β-globin promoter in erythroid cells. Herein we demonstrate that reducing the activity of USF decreased β-globin gene expression, while diminishing TFII-I activity increased β-globin gene expression in erythroid cell lines. Furthermore, a reduction of USF activity resulted in a significant decrease in acetylated H3, RNA polymerase II, and cofactor recruitment to the locus control region and to the adult β-globin gene. The data suggest that TFII-I and USF regulate chromatin structure accessibility and recruitment of transcription complexes in the β-globin gene locus and play important roles in restricting β-globin gene expression to the adult stage of erythropoiesis.

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