| First Author | Kotkow KJ | Year | 1995 |
| Journal | Mol Cell Biol | Volume | 15 |
| Issue | 8 | Pages | 4640-7 |
| PubMed ID | 7623856 | Mgi Jnum | J:28131 |
| Mgi Id | MGI:75761 | Doi | 10.1128/mcb.15.8.4640 |
| Citation | Kotkow KJ, et al. (1995) Dependence of globin gene expression in mouse erythroleukemia cells on the NF-E2 heterodimer. Mol Cell Biol 15(8):4640-7 |
| abstractText | High-level, tissue-specific expression of the beta-globin genes requires the presence of an upstream locus control region (LCR). The overall enhancer activity of the beta-globin complex LCR (beta-LCR) is dependent on the integrity of the tandem NF-E2 sites of HS-2. The NF-E2 protein which binds these sites is a heterodimeric basic leucine zipper protein composed of a tissue-specific subunit, p45 NF-E2, and a smaller subunit, p18 NF-E2, that is widely expressed. In these studies, we sought to investigate the role of NF-E2 in globin expression. We show that expression of a dominant-negative mutant p18 greatly reduces the amount of functional NF-E2 complex in the cell. Reduced levels of both alpha- and beta-globin were associated with the lower levels of NF-E2 activity in this cell line. Globin expression was fully restored upon the introduction of a tethered p45-p18 heterodimer. We also examined CB3 cells, a mouse erythroleukemia (MEL) cell line that does not express endogenous p45 NF-E2, and demonstrated that the restoration of globin gene expression was dependent upon the levels of expressed tethered NF-E2 heterodimer. Results of DNase I hypersensitivity mapping and in vivo footprinting assays showed no detectable chromatin alterations in beta-LCR HS-2 due to loss of NF-E2. Finally, we examined the specificity of NF-E2 for globin gene expression in MEL cells. These experiments indicate a critical role for the amino-terminal domain of p45 NF-E2 and show that a related protein, LCRF1, is unable to restore globin gene expression in p45 NF-E2-deficient cells.(ABSTRACT TRUNCATED AT 250 WORDS) |
