Publications & Reports

Intracellular retention of duck hepatitis B virus large surface protein is independent of preS topology.

Gazina EV, Lin B, Gallina A, Milanesi G, Anderson DA
Macfarlane Burnet Centre for Medical Research, Fairfield, Victoria, Australia.


The mechanism of intracellular retention for the large surface protein (L) of duck hepatitis B virus (DHBV) was analyzed by examination of the transmembrane topologies and secretory properties of a collection of DHBV L mutants and compared with that of human hepatitis B virus (HBV) L. Our results demonstrate that, in contrast to its HBV counterpart, intracellular retention of DHBV L does not depend on the cytosolic disposition of its preS domain. L mutants with either cytosolic or lumenal preS were mostly retained in the absence of the small surface protein (S), whereas coexpression with S resulted in efficient secretion of both topological forms. Coexpression of the wild-type DHBV L with S resulted in efficient incorporation of L into secreted S + L particles, whereas HBV L was partially excluded from secreted particles under the same conditions. We propose that HBV provides L retention even in the presence of an excess of S, by exclusion of molecules with cytosolic preS domains from secreted particles at the stage of their assembly. DHBV lacks such a retention mechanism due to the absence of topological selection in particulate assembly.


  • Journal: Virology
  • Published: 15/03/1998
  • Volume: 242
  • Issue: 2
  • Pagination: 266-278

Health Issue