Non-B-DNA structures on the interferon-beta promoter?
The high mobility group (HMG) I protein intervenes as an essential factor during the virus induced expression of the interferon-beta (IFN-beta) gene. It is a non-histone chromatine associated protein that has the dual capacity of binding to a non-B-DNA structure such as cruciform-DNA as well as to AT rich B-DNA sequences. In this work we compare the binding affinity of HMGI for a synthetic cruciform-DNA to its binding affinity for the HMGI-binding-site present in the positive regulatory domain II (PRDII) of the IFN-beta promoter. Using gel retardation experiments, we show that HMGI protein binds with at least ten times more affinity to the synthetic cruciform-DNA structure than to the PRDII B-DNA sequence. DNA hairpin sequences are present in both the human and the murine PRDII-DNAs. We discuss in this work the presence of, yet putative, non-B-DNA structures in the IFN-beta promoter.
Robbe
K
K
Laboratoire de Régulation de l'Expression des Gènes Eucaryotes, CNRS, UPR37, UFR Biomédicale, Université René-Descartes, Paris, France.
Bonnefoy
E
E
D001483:Base Sequence; D004247:DNA / Q000737:chemistry; D025741:HMGA1a Protein; D006609:High Mobility Group Proteins; D006801:Humans; D016899:Interferon-beta / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D014157:Transcription Factors
D006609:High Mobility Group Proteins; D014157:Transcription Factors; D025741:HMGA1a Protein; D016899:Interferon-beta; D004247:DNA