DNase I hypersensitive sites of the 5' region of the fibronectin gene of the liver of the rat.

We have mapped the DNase I hypersensitive sites (DH-sites) of the 5' region of the fibronectin (FNT) gene of the liver of the rat. These sites are not detectable in the cerebral hemisphere of the rat. Northern blot hybridization of the gene shows the presence of a 8 kb transcript in the liver which is induced by dexamethasone. Nuclear run on transcription shows that transcription of the FNT gene is much lower than that of the albumin gene in the liver. Gel mobility shift assay using nuclear extract of the liver shows the presence of a trans-acting factor which binds to the cAMP responsive element which overlaps with a DH-site in the region. There is thus good correlation between DH-sites of the FNT gene and its transcription in the liver.