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Comparative Study
. 2005 Mar;79(5):3139-45.
doi: 10.1128/JVI.79.5.3139-3145.2005.

Species-specific variation in the B30.2(SPRY) domain of TRIM5alpha determines the potency of human immunodeficiency virus restriction

Matthew Stremlau  1 , Michel Perron, Sohanya Welikala, Joseph Sodroski
Affiliations
Comparative Study

Species-specific variation in the B30.2(SPRY) domain of TRIM5alpha determines the potency of human immunodeficiency virus restriction

Matthew Stremlau et al. J Virol. 2005 Mar.

Abstract

Retroviruses encounter dominant postentry restrictions in cells of particular species. Human immunodeficiency virus type 1 (HIV-1) is blocked in the cells of Old World monkeys by TRIM5alpha, a tripartite motif (TRIM) protein composed of RING, B-box 2, coiled-coil, and B30.2(SPRY) domains. Rhesus monkey TRIM5alpha (TRIM5alpha(rh)) more potently blocks HIV-1 infection than human TRIM5alpha (TRIM5alpha(hu)). Here, by studying chimeric TRIM5alpha proteins, we demonstrate that the major determinant of anti-HIV-1 potency is the B30.2(SPRY) domain. Analysis of species-specific variation in TRIM5alpha has identified three variable regions (v1, v2, and v3) within the B30.2 domain. The TRIM5alpha proteins of Old World primates exhibit expansion, duplication, and residue variation specifically in the v1 region. Replacement of three amino acids in the N terminus of the TRIM5alpha(hu) B30.2 v1 region with the corresponding TRIM5alpha(rh) residues resulted in a TRIM5alpha molecule that restricted HIV-1 nearly as efficiently as wild-type TRIM5alpha(rh). Surprisingly, a single-amino-acid change in this region of TRIM5alpha(hu) allowed potent restriction of simian immunodeficiency virus, a phenotype not observed for either wild-type TRIM5alpha(hu) or TRIM5alpha(rh). Some of the chimeric TRIM5alpha proteins that are >98% identical to the human protein yet mediate a strong restriction of HIV-1 infection may have therapeutic utility. These observations implicate the v1 variable region of the B30.2(SPRY) domain in TRIM5alpha(rh) antiviral potency.

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Figures

FIG. 1.
FIG. 1.
Chimeric TRIM5αhu/TRIM5αrh proteins. A diagram of the TRIM5α protein is shown, with the known domains indicated (B2, B-box 2). The numbers of the residues at the N and C termini of the protein and at the chimeric junctions are indicated. The species-specific variable regions (v1, v2, and v3) within the B30.2 domain (28) are shown. The numbering scheme and nomenclature used for the chimeric proteins is based upon the TRIM5αhu sequence and is described in Materials and Methods.
FIG. 2.
FIG. 2.
Expression of chimeric TRIM5α proteins. Lysates from HeLa cells expressing the parental and chimeric TRIM5α proteins, which contain C-terminal HA epitope tags, were subjected to Western blotting with an antibody against HA. Control lysates from HeLa cells transduced with the empty pLPCX vector were analyzed in parallel. The lysates were also Western blotted with an antibody directed against β-actin.
FIG. 3.
FIG. 3.
Effects of expression of the chimeric TRIM5α proteins on HIV-1 infection. HeLa cells expressing the parental and chimeric TRIM5α proteins, or control HeLa cells transduced with the empty pLPCX vector, were incubated with various amounts of HIV-1-GFP or MLV-GFP. Infected GFP-positive cells were counted by FACS. The results of a typical experiment are shown. Similar results were obtained in three independent experiments. RT, reverse transcriptase.
FIG. 4.
FIG. 4.
Chimeric TRIM5α proteins containing heterologous elements of the B30.2 domain v1 region. A diagram of the TRIM5α B30.2 domain, with the variable regions (v1, v2, and v3) indicated is provided at the top of the figure. The region of interest is expanded, with the primary amino acid sequence of TRIM5αhu shown. Amino acid residues in TRIM5αrh that differ from those in TRIM5αhu are shown. The numbers refer to the human TRIM5α residue. The relevant segments of the chimeric TRIM5α proteins are shown. The white segments indicate that the protein is identical to TRIM5αhu except for the amino acid residues shown. The black segments indicate that the protein is identical to TRIM5αrh except for the indicated residues.
FIG. 5.
FIG. 5.
The N-terminal half of the B30.2 domain v1 region as a determinant of anti-HIV-1 potency. HeLa cells expressing the parental and chimeric TRIM5α proteins, or control HeLa cells transduced with the empty pLPCX vector, were incubated with various amounts of HIV-1-GFP or MLV-GFP. Infected, GFP-positive cells were counted by FACS. In the top row of panel A, a human TRIM5α variant [TRIM5α H(R323-332)] containing the N-terminal half of the rhesus monkey TRIM5α B30.2 domain v1 region was tested. In the bottom row of panel A and in panel B, TRIM5α chimerae containing heterologous segments other than the N-terminal portion of the B30.2 v1 region were tested. The results of typical experiments are shown. In panel A, the results of one experiment are separated into upper and lower rows for ease of viewing. Similar results were obtained in two independent experiments. RT, reverse transcriptase.
FIG. 6.
FIG. 6.
Expression and antiviral activities of mutant TRIM5α proteins. (A) Lysates from HeLa cells expressing the parental and mutant TRIM5α proteins, which contain C-terminal HA epitope tags, were subjected to Western blotting with an antibody against HA. Control lysates from HeLa cells transduced with the empty pLPCX vector were analyzed in parallel. The lysates were also Western blotted with an antibody directed against β-actin. (B and C) HeLa cells expressing TRIM5αrh, TRIM5αhu, or TRIM5αhu mutants or control HeLa cells transduced with the empty pLPCX vector were incubated with various amounts of HIV-1-GFP (B) or SIV-GFP (C). Infected GFP-positive cells were counted by FACS. The results of a typical experiment are shown. Similar results were obtained in two independent experiments. RT, reverse transcriptase.
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References

    1. Arts, E. J., and M. A. Wainberg. 1996. Human immunodeficiency type 1 reverse transcriptase and early events in reverse transcription. Adv. Virus Res. 46:97-163. - PubMed
    1. Barre-Sinoussi, F., J. C. Chermann, F. Rey, M. T. Nugeyre, S. Chamaret, J. Gruest, C. Dauguet, C. Axler-Blin, F. Vezinet-Brun, C. Rouzioux, W. Rosenbaum, and L. Montagnier. 1983. Isolation of a T-lymphotropic retrovirus from a patient at risk for acquired immunodeficiency syndrome (AIDS). Science 220:868-871. - PubMed
    1. Besnier, C., Y. Takeuchi, and G. Towers. 2002. Restriction of lentivirus in monkeys. Proc. Natl. Acad. Sci. USA 99:11920-11925. - PMC - PubMed
    1. Bieniasz, P. D. 2003. Restriction factors: a defense against retroviral infection. Trends Microbiol. 11:286-291. - PubMed
    1. Clavel, F. 1987. HIV-2, the West African AIDS virus. AIDS 1:135-140. - PubMed

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