Open AccessDifferential transcription of exon 1 of the human c-fms gene in placental trophoblasts and monocytes.
Author(s) -
Jane E. Visvader,
Inder M. Verma
Publication year - 1989
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.9.3.1336
Subject(s) - biology , exon , microbiology and biotechnology , intron , promoter , transcription (linguistics) , gene , exon trapping , tcf4 , northern blot , rna , gene expression , genetics , alternative splicing , linguistics , philosophy
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.