STRUCTURE, ORGANIZATION, AND TRANSCRIPTION UNITS OF THE HUMAN ALPHA-PLATELET-DERIVED GROWTH-FACTOR RECEPTOR GENE, PDGFRA

Isolation and characterization of genomic clones encoding human alpha- platelet derived growth factor receptor (HGMW-approved symbol PDGFRA) revealed that the gene spans approximately 65 kb and contains 23 exons . The 5'-untranslated region of the mRNA is encoded by exon 1, and a l arge intron of 23 kb separates exon 2 encoding the translation initiat or codon AUG and the signal sequence. The locations of exon/intron bou ndaries in the extracellular immunoglobulin-like domains, the transmem brane domain, the two cytoplasmic tyrosine kinase domains, and the kin ase insertion domain are very similar to those in c-kit and macrophage colony stimulating factor-1 receptor genes. The transcription start s ite was mapped to a position 393 bp upstream of the AUG translation in itiator codon by S1 mapping and primer extension analysis. The 5'-flan king region of the gene lacks a typical TATA box but contains a typica l CCAAT box and GATA motifs. This region also contains potential sites for AP-1, AP-2, Oct-1, Oct-2, and Sp1. The 5'-flanking region of the gene was fused to the luciferase reporter gene, and transcription unit s of the gene were determined. (C) 1995 Academic Press, Inc.