FIG. 1.

Enhancer I mutants derived from 10 patients chronically infected with the hepatitis B virus. (A) DNA binding sites in the HBV enhancer I-X promoter between nt 2364 and 2768 of the HBV genome (pre-C ATG = 1) are depicted. The binding motifs of the liver-specific transcription factors HNF3 and HNF4 are marked in boldface letters. Binding sites for other ubiquitous or liver-specific factors are also shown. (B) Sequence analysis of patient-derived enhancer I regions showing deletions and mutations in comparison to the wt HBV enhancer I region. Between nt 2526 and 2558, the enhancer I sequences are highlighted (boldface italics) to show the mutations found in patients 1 and 3.