[Structure, function and physiopathological implications of HNF-6, a prototype of a new family of gene expression regulators].

I describe here the identification and functional characterization of the mammalian transcription factor HNF-6. HNF-6 is the founding member of the new ONECUT class of factors. ONECUT proteins are characterized by the presence of a bipartite DNA-binding domain consisting in a single cut domain and a peculiar homeodomain. The expression of HNF-6 is restricted to liver, pancreas, brain, spleen and testis. In liver, it modulates the action of glucocorticoids and of growth hormone and controls development of the biliary system. Through its activity on pancreas development and on enzymes of liver glucose metabolism, HNF-6 is a regulator of glucose homeostasis. Our current work includes a further characterization of the role of HNF-6 in liver and pancreas development, and the identification of novel mammalian proteins of the ONECUT class.