Erythroid Expression of the Human α-Spectrin Gene Promoter Is Mediated by GATA-1- and NF-E2-binding Proteins

• Published in: The Journal of biological chemistry 2002-11, Vol.277 (44), p.41563
• Main Authors: Laurent Boulanger, Denise E. Sabatino, Ellice Y. Wong, Amanda P. Cline, Lisa J. Garrett, Michel Garbarz, Didier Dhermy, David M. Bodine, Patrick G. Gallagher
• Format: Article
• Language: English
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M208184200

α-Spectrin is a highly expressed membrane protein critical for the flexibility and stability of the erythrocyte. Qualitative and quantitative defects of α-spectrin are present in the erythrocytes of many patients with abnormalities of red blood cell shape including hereditary spherocytosis and elliptocytosis. We wished to determine the regulatory elements that determine the erythroid-specific expression of the α-spectrin gene. We mapped the 5′ end of the α-spectrin erythroid cDNA and cloned the 5′ flanking genomic DNA containing the putative α-spectrin gene promoter. Using transfection of promoter/reporter plasmids in human tissue culture cell lines, in vitro DNase I footprinting analyses, and gel mobility shift assays, an α-spectrin gene erythroid promoter with binding sites for GATA-1- and NF-E2-related proteins was identified. Both binding sites were required for full promoter activity. In transgenic mice, a reporter gene directed by the α-spectrin promoter was expressed in yolk sac, fetal liver, and erythroid cells of bone marrow but not adult reticulocytes. No expression of the reporter gene was detected in nonerythroid tissues. We conclude that this α-spectrin gene promoter contains the sequences necessary for low level expression in erythroid progenitor cells.