Macromolecular interaction on a cAMP responsive region in the urokinase-type plasminogen activator gene: a role of protein phosphorylation.
We have studied the regulation of urokinase-type plasminogen activator gene expression by cAMP in LLC-PK1 cells. We found a cAMP responsive region 3.4 kb upstream of the transcription initiation site, which comprised three protein-binding domains designated A, B, and C. Domains A and B both contain a sequence, TGACG, homologous to a consensus cAMP response element (CRE; TGACGTCA). Effective cAMP-mediated induction was achieved when these two domains were linked with domain C, which by itself did not confer cAMP responsiveness to a heterologous promoter nor contained CRE-like sequence, suggesting a functional cooperation among these domains. Results of competition studies using gel retardation and DNase I footprinting assays suggest that there is a protein-protein interaction between a CRE binding protein and a domain C binding protein. In gel retardation assays, binding of a nuclear protein to domains A and B was strongly augmented by addition of the catalytic subunit of cAMP-dependent protein kinase, whereas the protein binding to domain C was slightly inhibited, suggesting that protein phosphorylation is involved in the regulation of protein-DNA interaction.
von der Ahe
D
D
Friedrich Miescher-Institut, CH-4002 Basel, Switzerland.
Pearson
D
D
Nagamine
Y
Y
D001483:Base Sequence; D001667:Binding, Competitive; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D005796:Genes; D008969:Molecular Sequence Data; D010766:Phosphorylation; D010960:Plasminogen Activators / Q000235:genetics* / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D014158:Transcription, Genetic; D014568:Urokinase-Type Plasminogen Activator / Q000235:genetics* / Q000378:metabolism
D004268:DNA-Binding Proteins; D004247:DNA; D000242:Cyclic AMP; D010960:Plasminogen Activators; D014568:Urokinase-Type Plasminogen Activator