Open AccessIncorporation of Eukaryotic Translation Initiation Factor eIF4E into Viral Nucleocapsids via Interaction with Hepatitis B Virus Polymerase
Author(s) -
Seahee Kim,
Haifeng Wang,
WangShick Ryu
Publication year - 2010
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.01232-09
Subject(s) - biology , eif4e , virology , ribonucleoprotein , polymerase , eukaryotic translation , transcription (linguistics) , viral life cycle , rna , initiation factor , viral replication , microbiology and biotechnology , translation (biology) , virus , genetics , messenger rna , dna , gene , linguistics , philosophy
The DNA genome of hepatitis B virus (HBV) replicates via reverse transcription within capsids following the encapsidation of an RNA template, the pregenomic RNA (pgRNA). We previously demonstrated that the 5′ cap proximity of the stem-loop structure (ε or epsilon), an encapsidation signal, is critically important for the encapsidation of the pgRNA (J. K. Jeong, G. S. Yoon, and W. S. Ryu, J. Virol.74: 5502-5508, 2000). Therefore, we speculated that the viral polymerase (Pol), while bound to the 5′ ε stem-loop structure, could recognize the cap via its interaction with eIF4E, a eukaryotic translation initiation factor. Our data showed the direct interaction between HBV Pol and eIF4E, as measured by coimmunoprecipitation. Further, we demonstrated that eIF4E interacts with the Pol-ε ribonucleoprotein complex (RNP) rather than Pol alone, resulting in eIF4E-Pol-ε RNP complex formation. In addition, we asked whether eIF4E remains engaged to the Pol-ε RNP complex during nucleocapsid assembly. Density gradient analysis revealed that eIF4E indeed was incorporated into nucleocapsids. It is of great importance to uncover whether the incorporated eIF4E contributes to viral reverse transcription or other steps in the HBV life cycle.