Two distinct regions of the mouse beta Fc gamma R gene control its transcription.

INSERM U. 255, Institut Curie, France.
Immunobiology (Impact Factor: 2.81). 09/1992; 185(2-4):222-34.
Source: PubMed

ABSTRACT The low-affinity receptors for the Fc portion of IgG (Fc gamma RII and Fc gamma RIII) are born by most of the immunocompetent cells and mediate a wide spectrum of biological activities. Macrophages, mast cells and lymphocytes express the type II Fc gamma R whereas the type III Fc gamma R is expressed on macrophages, mast cells and NK cells. In mice, the beta Fc gamma R gene codes for Fc gamma RII and the alpha Fc gamma R gene codes for the ligand-binding Fc gamma RIII alpha-chain. We have previously demonstrated that the methylation of the 5' region of these genes control their expression. In the present paper, we investigate the role of two unmethylated regions of the beta gene, the promoter and the third intron, in the control of its transcription. We show, by using two cell lines representative of B and mast cells, that different promoter fragments determine, in these two cell types, the transcription of the beta Fc gamma R gene. The third intron of the beta Fc gamma R gene contains sequences, which, introduced upstream to homologous or heterologous promoter, inhibit the transcriptional activity of these promoter. Thus, in B cells and in mast cells, the transcription of the beta Fc gamma R gene is controlled by two distinct regions of the gene.

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