Differential transcription of exon 1 of the human c-fms gene in placental trophoblasts and monocytes.
Article Details
- CitationCopy to clipboard
Visvader J, Verma IM
Differential transcription of exon 1 of the human c-fms gene in placental trophoblasts and monocytes.
Mol Cell Biol. 1989 Mar;9(3):1336-41.
- PubMed ID
- 2524648 [ View in PubMed]
- Abstract
Structural analysis of the 5' end of the human c-fms gene revealed that a large intron of about 25 kilobases separates an upstream noncoding exon (exon 1) from the signal peptide-containing exon (exon 2). Northern (RNA) blot analysis, S1 nuclease mapping, and primer extensions showed that exon 1 is transcribed in placenta but not in cells of the monocytic lineage. This is due to the differential usage of promoters, separated by approximately 25 kilobases, in a cell-specific manner. One major c-fms transcript was observed in U-937 cells, whereas multiple initiation sites for transcription appeared to be utilized in placental cells. Nucleotide sequence comparisons showed that the 3' end of the human platelet-derived growth factor receptor gene lies approximately 350 base pairs upstream of the major initiation sites for c-fms transcription in placental trophoblasts.