Cloning and sequencing of cDNAs encoding the human hepatocyte nuclear factor 4 indicate the presence of two isoforms in human liver.

Hepatocyte nuclear factor 4 (HNF-4) is a key transcription factor involved in the specific expression of many genes in liver and intestine. Sequences of cDNAs coding for HNF-4 have been established in rat and Drosophila melanogaster. Rat HNF-4 exhibits two isoforms which probably result from differential splicing. We have isolated HNF-4 cDNAs from an adult human cDNA library. Sequence analysis revealed that two HNF-4 isoforms are also present in human liver. The complete sequence of the longest human isoform has been established and compared to the rat HNF-4 amino-acid sequences.