A Vestigial X Open Reading Frame in Duck Hepatitis B Virus

@article{Lin2000AVX,
  title={A Vestigial X Open Reading Frame in Duck Hepatitis B Virus},
  author={Bo Lin and David A. Anderson},
  journal={Intervirology},
  year={2000},
  volume={43},
  pages={185 - 190}
}
Duck hepatitis B virus (DHBV) appears to lack a homologue of the X protein found in mammalian hepadnaviruses. By replacing stop codons in the corresponding region of the DHBV genome, a hypothetical protein which closely matches the hydrophilicity profile of X proteins can be predicted, despite limited sequence homology. We conclude that a full-length X protein was once a common feature of the hepadnaviruses, conserved in structure but not sequence. 

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