Transcription of the mouse secretory protease inhibitor p12 gene is activated by the developmentally regulated positive transcription factor Sp1.
We have previously shown that a trans-acting protein produced in some tissue culture cells positively control the transcriptional activity directed by the mouse p12 promoter. This nuclear protein exerts its positive activity by interacting with a regulatory sequence designated p12.A and located between the TATA and CCAAT box elements on the p12 gene promoter. Using DNase I and dimethyl sulfate methylation interference footprinting techniques coupled with gel retardation assays, we found evidence that the protein which binds to the p12.A element is the well-known transcription factor Sp1. Mutational analysis in transient transfection assays confirmed the positive activity exerted by this protein in every cell line tested. In agreement with this observation, we detected a p12.A-Sp1 binding activity in nuclear extracts prepared from all cell lines used. However, a similar binding activity could not be detected in a number of nuclear extracts prepared from normal mouse tissues. In this report, we provide the evidence that the lack of Sp1-binding activity results from the degradation of Sp1 in the kidney, liver, and pancreas of the mouse.
Robidoux
S
S
Centre de Recherche en Endocrinologie Moléculaire, Centre Hospitalier de l'Université Laval, Ste-Foy, Québec, Canada.
Gosselin
P
P
Harvey
M
M
Leclerc
S
S
Guérin
S L
SL
D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D004247:DNA; D005260:Female; D005786:Gene Expression Regulation; D008297:Male; D008745:Methylation; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D011480:Protease Inhibitors / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection; D015032:Zinc / Q000378:metabolism
D011480:Protease Inhibitors; D016329:Sp1 Transcription Factor; D004247:DNA; D015032:Zinc