Open AccessEquine Infectious Anemia Virus and the Ubiquitin-Proteasome System
Author(s) -
David E. Ott,
Lori V. Coren,
Raymond C. Sowder,
Julian Adams,
Kunio Nagashima,
Ulrich S. Schubert
Publication year - 2002
Publication title -
journal of virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.617
H-Index - 292
eISSN - 1070-6321
pISSN - 0022-538X
DOI - 10.1128/jvi.76.6.3038-3044.2002
Subject(s) - equine infectious anemia , biology , proteasome , ubiquitin , retrovirus , virus , virology , murine leukemia virus , immunoprecipitation , microbiology and biotechnology , group specific antigen , friend virus , cell culture , biochemistry , gene , genetics
Some retroviruses contain monoubiquitinated Gag and do not bud efficiently from cells treated with proteasome inhibitors, suggesting an interaction between the ubiquitin-proteasome system and retrovirus assembly. We examined equine infectious anemia virus (EIAV) particles and found that approximately 2% of the p9(Gag) proteins are monoubiquitinated, demonstrating that this Gag protein interacts with an ubiquitinating activity. Different types of proteasome inhibitors were used to determine if proteasome inactivation affects EIAV release from chronically infected cells. Pulse-chase immunoprecipitation and time course immunoblot analyses showed that proteasome inactivation slightly decreased virus release (at most a twofold effect), while it did not affect Gag processing. These results contrast with those obtained with other viruses which are sensitive to these inhibitors. This suggests that, although its Gag is monoubiquitinated, the requirements for EIAV release are somewhat different from those for retroviruses that are sensitive to proteasome inhibitors.