| First Author | Loyd MR | Year | 2003 |
| Journal | Blood | Volume | 102 |
| Issue | 12 | Pages | 4223-8 |
| PubMed ID | 12920035 | Mgi Jnum | J:86682 |
| Mgi Id | MGI:2681069 | Doi | 10.1182/blood-2003-02-0574 |
| Citation | Loyd MR, et al. (2003) Role of AP1/NFE2 binding sites in endogenous alpha-globin gene transcription. Blood 102(12):4223-8 |
| abstractText | High-level alpha-globin expression depends on cis-acting regulatory sequences located far upstream of the alpha-globin cluster. Sequences that contain the alpha-globin positive regulatory element (PRE) activate alpha-globin expression in transgenic mice. The alpha-globin PRE contains a pair of composite binding sites for the transcription factors activating protein 1 and nuclear factor erythroid 2 (AP1/NFE2). To determine the role of these binding sites in alpha-globin gene transcription, we mutated the AP1/NFE2 sites in the alpha-globin PRE in mice. We replaced the AP1/NFE2 sites with a neomycin resistance gene (neo) that is flanked by LoxP sites (floxed). Mice with this mutation exhibited increased embryonic death and alpha-thalassemia intermedia. Next, we removed the neo gene by Cre-mediated recombination, leaving a single LoxP site in place of the AP1/NFE2 sites. These mice were phenotypically normal. However, alpha-globin expression, measured by allele-specific RNA polymerase chain reaction (PCR), was decreased 25%. We examined the role of the hematopoietic-restricted transcription factor p45Nfe2 in activating expression through these sites and found that it is not required. Thus, we have demonstrated that AP1/NFE2 binding sites in the murine alpha-globin PRE contribute to long-range alpha-globin gene activation. The proteins that mediate this effect remain to be determined. |
