Hepatocyte nuclear factor 6, a transcription factor that contains a novel type of homeodomain and a single cut domain

Tissue-specific transcription is regulated in part by cell type-restricted proteins that bind to defined sequences in target genes, The DNA-binding domain of these proteins is often evolutionarily conserved, On this basis, Liver-enriched transcription factors were classified into five families. We describe here the mammalian prototype of a sixth family, which we therefore call hepatocyte nuclear factor 6 (HNF-6). It activates the promoter of a gene involved in the control of glucose metabolism, HNF-6 contains two different DNA-binding domains, One of these corresponds to a novel type of homeodomain. The other is homologous to the Drosophila cut domain. A similar bipartite sequence is coded by the genome of Caenorhabditis elegans.