Purification of a NF1-like DNA-binding protein from rat liver and cloning of the corresponding cDNA

Abstract

NF1-like proteins play a role in transcription of liver-specific genes. A DNA-binding protein, recognizing half of the canonical NF1 binding site (TGGCA) present on the human albumin and retinol-binding protein genes, has been purified from rat liver. Several peptides deriving from a tryptic digest of the purified protein were sequenced and the sequence was used to synthesize specific oligonucleotides. Two overlapping cDNA clones were obtained from a rat-liver cDNA library; their sequence reveals an open reading frame coding for 505 amino acids, including all the peptides sequenced from the purified protein. The DNA-binding domain, most likely located within the first 250 amino acids, is highly homologous to the sequence of CTF/NF1 purified from HeLa cells. Northern analysis reveals several mRNA species present in different combinations in various rat tissues.