Regulated expression of genes in the beta-globin cluster depends upon sequences located between 5 and 20 kb upstream of the epsilon gene, known as the locus control region (LCR). beta-Globin expression in murine erythroleukemia (MEL) cells depends on NF-E2, a transcription factor which binds to enhancer sequences in the LCR. To gain insight into the mechanism of globin gene activation by NF-E2,...

The mouse beta-globin gene locus control region (LCR), located upstream of the beta-globin gene cluster, is essential for the activated transcription of genes in the cluster. The LCR contains multiple binding sites for transactivators, including Maf-recognition elements (MAREs). However, little is known about the specific proteins that bind to these sites or the time at which they bind during e...

We have identified a folate receptor gene upstream of the chicken beta-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 beta-globin genes, consistent with the role of folate receptors in proliferation. This discovery raises the question of how these ...

Adult erythrocytes of X. laevis contain six electrophoretically resolvable globin polypeptides while tadpole erythrocytes contain four polypeptides, none of which comigrates with an adult protein. We show that three of the adult proteins are alpha globin polypeptides (alpha 1, alpha 2, alpha 3) and three are beta globin polypeptides (beta 1, beta 2, beta 3). We find that a tadpole alpha globin ...

We have identified two new histone deacetylase (HDAC) inhibitors (9 and 24) capable of inducing the expression of gamma-globin and/or beta-globin promoter-driven reporter genes in a synthetic model of Hb switch. Both compounds also increased, with different mechanisms, the gamma/(gamma+beta) ratio expressed in vitro by normal human erythroblasts. Compound 9 increased the levels of gamma-globin ...

We have examined whether transfected mouse erythroleukaemia (MEL) cells can be used to examine differential expression of human gamma- and beta-globin genes. These cells, which express only their adult globin genes, will transcribe the human adult beta gene but not the fetal gamma genes when they are introduced on an intact human chromosome 11 by cell fusion. However, MEL cells stably transfect...

Mutations producing beta-thalassemia reach individual gene frequencies greater than .01 in malarial-endemic regions because beta-thalassemia trait individuals have increased genetic fitness over that of normal individuals. Exon 3 of the beta-globin gene has been relatively spared as a site of common beta-thalassemia mutations. Frameshifts caused by the loss of a single nucleotide and nonsense m...

Gene therapy for hemoglobinopathies requires efficient gene transfer into hematopoietic stem cells and high-level erythroid-specific gene expression. Toward this goal, we constructed a helper-dependent adenovirus vector carrying the beta-globin locus control region (LCR) to drive green fluorescent protein (GFP) expression, whereby the LCR-GFP cassette is flanked by adeno-associated virus (AAV) ...

Human beta-globin was synthesized in Escherichia coli as a cleavable fusion protein, using the expression vector pLcIIFX beta-globin [Nagai, K. & Thøgersen, H. C. (1984) Nature (London) 309, 810-812]. The fusion protein cIIFX beta-globin was purified to homogeneity and cleaved at the junction by blood coagulation factor Xa; the authentic beta-globin was liberated. Beta-globin was folded in vitr...

Species differences in the size or membership composition of multigene families can be attributed to lineage-specific additions of new genes via duplication, losses of genes via deletion or inactivation, and the creation of chimeric genes via domain shuffling or gene fusion. In principle, it should be possible to infer the recombinational pathways responsible for each of these different types o...