The transcription factors Elf-1 and GATA-1 bind to cell-specific enhancer elements of human high-affinity IgE receptor alpha-chain gene

Key regulatory regions necessary for the expression of the gene encoding Fc epsilon RI alpha-chain, a component of the high-affinity IgE receptor prim arily responsible for IgE-dependent allergic response, were investigated. T wo regions, -74/-69 and -55/-47, which contained binding motifs for protein s belonging to the Ets family and the GATA family, respectively, were shown to be necessary for the activation of the Lu-chain promoter. Both the regu latory elements enhanced the promoter activity only in alpha-chain-producin g cells PT18 and RBL-2H3 (mast cell lines), indicating that the elements re quired specific trans-acting proteins present in the alpha-chain-producing cells. EMSA using nuclear extracts and in vitro-translated proteins reveale d that Elf-1 and GATA-1 bound to the enhancer elements. This is the first r eport describing the regulation in the expression of the Fc epsilon RI alph a-chain.