Expression of the rat growth‐hormone gene is under the influence of a cell‐type‐specific silencer element

• Published in: European journal of biochemistry Vol. 213; no. 1; pp. 399 - 404
• Main Authors: GUÉRIN, Sylvain L., ANZIVINO, Matthew J., ROY, René J., MOORE, David D.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.1993; Blackwell
• Subjects: Analytical, structural and metabolic biochemistry; Animals; Base Sequence; Biological and medical sciences; Cells, Cultured; DNA - metabolism; Fundamental and applied biological sciences. Psychology; Growth Hormone - genetics; HeLa Cells; Humans; Mice; Molecular Sequence Data; Nuclear Proteins - metabolism; Protein Binding; Protein hormones. Growth factors. Cytokines; Proteins; Rats; Recombinant Proteins - genetics; Regulatory Sequences, Nucleic Acid; Rat; Copy number; STH; Rodentia; IS element; Plasmid; Protein hormone; Vertebrata; Mammalia; Messenger RNA; Type specificity; Gene; Trans acting regulatory factor
• ISSN: 0014-2956; 1432-1033
• DOI: 10.1111/j.1432-1033.1993.tb17774.x

We have previously shown that a cell‐type‐specific negative‐regulatory element, or silencer, acts to specifically restrict rat‐growth‐hormone(rGH)‐promoter activity to pituitary cells. Here we report a detailed characterization of this element. The activity of the silencer is dependent on its position relative to the promoter. The negative regulatory effect can be diminished by cotransfection with a high‐copy‐number, silencer‐containing competitor plasmid, suggesting that the function of the element is mediated by specific binding of a trans‐acting negative‐regulatory factor. The minimal region required for silencer function is contained between positions −309 and −266 relative to the start of the rGH mRNA. The specific interaction of a nuclear protein from non‐pituitary cells with this rGH DNA segment was shown by DNasel as well as dimethylsulfate methylation‐interference footprinting. A detailed examination of the DNA‐binding site for that protein clearly suggest that it belongs to the NF1 family of transcription factors.