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The endogenous langur type D retrovirus PO-1-Lu and its exogenous counterparts in macaque and langur monkeys

Maja A Sommerfelt1, Nina Harkestad, Eric Hunter

  • 1Centre for Research in Virology, Department of Microbiology and Immunology, The Gade Institute, University of Bergen, Bergen High Technology Centre, N-5020 Bergen, Norway. maja.sommerfelt@vir.uib.no

Virology
|October 31, 2003
PubMed

Insights

This study reevaluates the origin of type D retroviruses. PO-1-Lu and SRV-6, found in langurs, are genetically closer to SRV-2 than previously thought, suggesting a new zoonotic origin hypothesis.

Area of Science:

  • Virology
  • Genomics
  • Primate Health

Background:

  • The endogenous type D retrovirus PO-1-Lu in langurs was thought to precede Mason Pfizer monkey virus (M-PMV/SRV-3) in macaques.
  • Previous hypotheses did not fully account for other exogenous simian retroviruses (SRVs).

Purpose of the Study:

  • To reevaluate the progenitor hypothesis of PO-1-Lu in relation to M-PMV and other exogenous SRVs.
  • To investigate the genetic and antigenic relationships between PO-1-Lu, SRV-6, and other type D retroviruses.

Main Methods:

  • Phylogenetic analysis of env gene nucleotide sequences using neighbor-joining and bootstrapping.
  • Antigenic characterization of envelope glycoproteins (gp70(SU) and gp22(TM)) of M-PMV and PO-1-Lu.

Main Results:

  • PO-1-Lu shows striking sequence similarity to the newly identified langur retrovirus SRV-6.
  • Phylogenetic analysis indicates PO-1-Lu and SRV-6 are more closely related to SRV-2 than to SRV-1 or SRV-3 (M-PMV).
  • Antigenic analysis revealed distinct M-PMV gp70(SU) but cross-reactive gp22(TM) glycoproteins with PO-1-Lu.

Conclusions:

  • The findings challenge the previous progenitor hypothesis for M-PMV.
  • SRV-6 may represent an exogenous form of PO-1-Lu arising from a recent zoonotic event.
  • Further investigation into the evolutionary dynamics of type D retroviruses in langurs and macaques is warranted.

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