Analysis of the 5' promoters for human IL-3 and GM-CSF receptor alpha genes.
The receptors for human interleukin-3 (hIL-3R) and granulocyte-macrophage colony-stimulating factor (hGM-CSFR) consist of an alpha subunit, specific for each cytokine, and a beta subunit, common to IL-3, GM-CSF, and IL-5. We cloned genomic DNA covering 1.5 kb of the 5' flanking region of the hIL-3R alpha gene and identified multiple transcription start sites by 5(')-RACE and primer extension analyses. By use of transient transfection experiments, two regions (nt -363 to -331 and -106 to -92) of the hIL-3R alpha promoter appeared to have significant transcription-enhancing activities. Electrophoresis mobility shift assays revealed the binding of Sp1 and unidentified proteins to these regions. Deletion of a putative PU.1 binding site did not affect the promoter activity. We then analyzed 2.5 kb of the hGM-CSFR alpha gene and found the proximal PU.1 binding site to be important for transcription-enhancing activity, as previously reported. These results suggest that different transcriptional activation mechanisms are employed for the transcriptional regulation of hIL-3 and hGM-CSF receptor alpha genes.
Akagawa
Eiji
E
Department of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
Muto
Akihiko
A
Arai
Ken-ichi
K
Watanabe
Sumiko
S
D024506:5' Flanking Region; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D053650:Interleukin-3 Receptor alpha Subunit; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000502:physiology; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics*; D016185:Receptors, Interleukin-3 / Q000235:genetics*; D015534:Trans-Activators / Q000502:physiology; D024363:Transcription Initiation Site; D015533:Transcriptional Activation; D000099232:Proto-Oncogene Protein Spi-1
D004268:DNA-Binding Proteins; D053650:Interleukin-3 Receptor alpha Subunit; D011518:Proto-Oncogene Proteins; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor; D016185:Receptors, Interleukin-3; D015534:Trans-Activators; D000099232:Proto-Oncogene Protein Spi-1; C115022:IL3RA protein, human