Perivenous expression of the mRNA of the three hypoxia-inducible factor alpha-subunits, HIF1alpha, HIF2alpha and HIF3alpha, in rat liver.

The cDNAs of three hypoxia-inducible factor (HIF) alpha-subunits were cloned from RNA of primary rat hepatocytes by reverse transcriptase PCR. All three cDNAs encoded functionally active proteins, of 825, 874 and 662 amino acids. After transfection they were able to activate luciferase activity of a luciferase gene construct containing three HIF-responsive elements. The mRNAs of the rat HIF alpha-subunits were expressed predominantly in the perivenous zone of rat liver tissue; the nuclear HIFalpha proteins, however, did not appear to be zonated.