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Multiple sites in the N-terminal half of simian immunodeficiency virus capsid protein contribute to evasion from rhesus monkey TRIM5α-mediated restriction.

Kono K, Song H, Yokoyama M, Sato H, Shioda T, Nakayama EE - Retrovirology (2010)

Bottom Line: In addition, the N-terminal portion (from the 5th to 12th amino acid residues) and the 107th and 109th amino acid residues in α-helix 6 of SIVmac CA are necessary for complete evasion from Rh TRIM5α-mediated restriction.A three-dimensional model of hexameric GH123 CA showed that these multiple regions are located on the CA surface, suggesting their direct interaction with TRIM5α.We found that multiple regions of the SIVmac CA are necessary for complete evasion from Rh TRIM5α restriction.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan.

ABSTRACT

Background: We previously reported that cynomolgus monkey (CM) TRIM5α could restrict human immunodeficiency virus type 2 (HIV-2) strains carrying a proline at the 120th position of the capsid protein (CA), but it failed to restrict those with a glutamine or an alanine. In contrast, rhesus monkey (Rh) TRIM5α could restrict all HIV-2 strains tested but not simian immunodeficiency virus isolated from macaque (SIVmac), despite its genetic similarity to HIV-2.

Results: We attempted to identify the viral determinant of SIVmac evasion from Rh TRIM5α-mediated restriction using chimeric viruses formed between SIVmac239 and HIV-2 GH123 strains. Consistent with a previous study, chimeric viruses carrying the loop between α-helices 4 and 5 (L4/5) (from the 82nd to 99th amino acid residues) of HIV-2 CA were efficiently restricted by Rh TRIM5α. However, the corresponding loop of SIVmac239 CA alone (from the 81st to 97th amino acid residues) was not sufficient to evade Rh TRIM5α restriction in the HIV-2 background. A single glutamine-to-proline substitution at the 118th amino acid of SIVmac239 CA, corresponding to the 120th amino acid of HIV-2 GH123, also increased susceptibility to Rh TRIM5α, indicating that glutamine at the 118th of SIVmac239 CA is necessary to evade Rh TRIM5α. In addition, the N-terminal portion (from the 5th to 12th amino acid residues) and the 107th and 109th amino acid residues in α-helix 6 of SIVmac CA are necessary for complete evasion from Rh TRIM5α-mediated restriction. A three-dimensional model of hexameric GH123 CA showed that these multiple regions are located on the CA surface, suggesting their direct interaction with TRIM5α.

Conclusion: We found that multiple regions of the SIVmac CA are necessary for complete evasion from Rh TRIM5α restriction.

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Western blot analysis of lysates of viral producer cells and viral particles. Viral proteins in the lysate of equal number of viral producer cells (upper panel) and particle fraction of equal volume of culture supernatant of viral producer cells (lower panel) were visualized by WB using serum from an SIV-infected monkey.
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Figure 6: Western blot analysis of lysates of viral producer cells and viral particles. Viral proteins in the lysate of equal number of viral producer cells (upper panel) and particle fraction of equal volume of culture supernatant of viral producer cells (lower panel) were visualized by WB using serum from an SIV-infected monkey.

Mentions: Finally, we checked viral release and maturation/processing of GH123, SIVmac239, and their derivative viruses by a western blot for the lysate of viral producer cells (Figure 6, upper panel) and viral particles (Figure 6, lower panel), since viral maturation is essential for TRIM5α recognition. CA proteins in the cells and released viral particles were clearly detected. CAs with SIVmac239 L4/5 showed slightly reduced mobility compared with those with GH123 L4/5. Although there were small differences in the amounts of CA among viruses tested, there was no difference in the ratio of intracellular CA to those in the released viral particles. It should be also mentioned that there was no difference in the ratio of Gag precursors to processed CA in the viral producer cells. These results indicated that viral release and maturation/processing of the derivative viruses occurred normally.


Multiple sites in the N-terminal half of simian immunodeficiency virus capsid protein contribute to evasion from rhesus monkey TRIM5α-mediated restriction.

Kono K, Song H, Yokoyama M, Sato H, Shioda T, Nakayama EE - Retrovirology (2010)

Western blot analysis of lysates of viral producer cells and viral particles. Viral proteins in the lysate of equal number of viral producer cells (upper panel) and particle fraction of equal volume of culture supernatant of viral producer cells (lower panel) were visualized by WB using serum from an SIV-infected monkey.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2944288&req=5

Figure 6: Western blot analysis of lysates of viral producer cells and viral particles. Viral proteins in the lysate of equal number of viral producer cells (upper panel) and particle fraction of equal volume of culture supernatant of viral producer cells (lower panel) were visualized by WB using serum from an SIV-infected monkey.
Mentions: Finally, we checked viral release and maturation/processing of GH123, SIVmac239, and their derivative viruses by a western blot for the lysate of viral producer cells (Figure 6, upper panel) and viral particles (Figure 6, lower panel), since viral maturation is essential for TRIM5α recognition. CA proteins in the cells and released viral particles were clearly detected. CAs with SIVmac239 L4/5 showed slightly reduced mobility compared with those with GH123 L4/5. Although there were small differences in the amounts of CA among viruses tested, there was no difference in the ratio of intracellular CA to those in the released viral particles. It should be also mentioned that there was no difference in the ratio of Gag precursors to processed CA in the viral producer cells. These results indicated that viral release and maturation/processing of the derivative viruses occurred normally.

Bottom Line: In addition, the N-terminal portion (from the 5th to 12th amino acid residues) and the 107th and 109th amino acid residues in α-helix 6 of SIVmac CA are necessary for complete evasion from Rh TRIM5α-mediated restriction.A three-dimensional model of hexameric GH123 CA showed that these multiple regions are located on the CA surface, suggesting their direct interaction with TRIM5α.We found that multiple regions of the SIVmac CA are necessary for complete evasion from Rh TRIM5α restriction.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan.

ABSTRACT

Background: We previously reported that cynomolgus monkey (CM) TRIM5α could restrict human immunodeficiency virus type 2 (HIV-2) strains carrying a proline at the 120th position of the capsid protein (CA), but it failed to restrict those with a glutamine or an alanine. In contrast, rhesus monkey (Rh) TRIM5α could restrict all HIV-2 strains tested but not simian immunodeficiency virus isolated from macaque (SIVmac), despite its genetic similarity to HIV-2.

Results: We attempted to identify the viral determinant of SIVmac evasion from Rh TRIM5α-mediated restriction using chimeric viruses formed between SIVmac239 and HIV-2 GH123 strains. Consistent with a previous study, chimeric viruses carrying the loop between α-helices 4 and 5 (L4/5) (from the 82nd to 99th amino acid residues) of HIV-2 CA were efficiently restricted by Rh TRIM5α. However, the corresponding loop of SIVmac239 CA alone (from the 81st to 97th amino acid residues) was not sufficient to evade Rh TRIM5α restriction in the HIV-2 background. A single glutamine-to-proline substitution at the 118th amino acid of SIVmac239 CA, corresponding to the 120th amino acid of HIV-2 GH123, also increased susceptibility to Rh TRIM5α, indicating that glutamine at the 118th of SIVmac239 CA is necessary to evade Rh TRIM5α. In addition, the N-terminal portion (from the 5th to 12th amino acid residues) and the 107th and 109th amino acid residues in α-helix 6 of SIVmac CA are necessary for complete evasion from Rh TRIM5α-mediated restriction. A three-dimensional model of hexameric GH123 CA showed that these multiple regions are located on the CA surface, suggesting their direct interaction with TRIM5α.

Conclusion: We found that multiple regions of the SIVmac CA are necessary for complete evasion from Rh TRIM5α restriction.

Show MeSH
Related in: MedlinePlus