CHARACTERIZATION OF THE MOUSE RON STK RECEPTOR TYROSINE KINASE GENE/

In an effort to understand the mechanisms governing the regulation of the mouse Ron receptor gene, a mouse genomic library was screened and overlapping clones coding for the Ron gene and flanking DNA were ident ified, Continuous DNA sequence was obtained for approximately 16.4 kil obases, The gene, from the initiator methionine to the polyadenylation site, is contained within 13 244 basepairs and contains 19 exons, Pri mer extension analyses were performed to determine the transcription s tart site of the mouse Ron transcript, Multiple transcription start si tes were found which also appear to be used in transfected reporter co nstructs containing Ron 5' flanking DNA, To determine the location of sites which may be critical for the function of the Ron gene promoter, a series of chimeric genes containing serial deletions of the Ron gen e promoter fused to the coding sequences for the chloramphenicol acety l-transferase gene were constructed, Transient transfection analyses o f these hybrid genes into various cell lines demonstrated that two reg ions of the Ron gene promoter, encompassing nucleotides -585 to -465 a nd from -465 to -285, are important for expression of this transcript in CMT-93 cells, Further analysis of the Ron promoter utilizing gel mo bility shift analyses suggests that regions encompassing nucleotides - 585 to -508 and nucleotides -375 to -285 appear to bind specific prote ins which may be involved in the negative and positive regulation, res pectively, of the mouse Ron gene.