Zeta PKC plays a critical role during stromelysin promoter activation by platelet-derived growth factor through a novel palindromic element.
Stromelysin is a metalloproteinase with the widest substrate specificity that plays a critical role in the induction of the metastatic phenotype in cancer cells. The mechanisms whereby growth factors and oncogenes control stromelysin expression are beginning to be characterized. We have recently demonstrated that protein kinase C isotypes down-regulatable by chronic exposure to phorbol esters are not involved in stromelysin gene expression in response to platelet-derived growth factor, ras oncogene, and phosphatidylcholine-hydrolyzing phospholipase C. We also identified a region in the stromelysin promoter, distinct from the 12-O-tetradecanoylphorbol-13-acetate-responsive element, responsible for the promoter activity in response to these stimulants. In this paper, we further characterize that promoter fragment and demonstrate that the region encompassing nucleotides -1218 to -1202, including the palindromic sequence ACTAGT, is necessary and sufficient for the control of stromelysin gene expression. The involvement of zeta-protein kinase C but not of c-raf in the stimulation of stromelysin promoter activity in response to platelet-derived growth factor is also demonstrated here. All these data suggest the existence of a bifurcation downstream of ras in the signaling mechanisms leading to stromelysin expression and DNA synthesis.
Sanz
L
L
Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autonoma de Madrid, Canto Blanco, Spain.
Berra
E
E
Municio
M M
MM
Dominguez
I
I
Lozano
J
J
Johansen
T
T
Moscat
J
J
Diaz-Meco
M T
MT
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D019278:Matrix Metalloproteinase 3; D008666:Metalloendopeptidases / Q000096:biosynthesis* / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000187:drug effects; D011493:Protein Kinase C / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019908:Proto-Oncogene Proteins c-raf; D011519:Proto-Oncogenes; D015183:Restriction Mapping; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection
D017931:DNA Primers; D007527:Isoenzymes; D009363:Neoplasm Proteins; D010982:Platelet-Derived Growth Factor; D011518:Proto-Oncogene Proteins; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D011493:Protein Kinase C; D008666:Metalloendopeptidases; D019278:Matrix Metalloproteinase 3; D013755:Tetradecanoylphorbol Acetate