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Abstract
HIV type 1 (HIV-1) has a very narrow host range that is limited to humans and chimpanzees. HIV-1 cannot replicate well in Old World monkey cells such as rhesus and cynomolgus monkeys. Tripartite motif (TRIM)5α is a key molecule that confers potent resistance against HIV-1 infection and is composed of really interesting new gene, B-box2, coiled-coil and PRYSPRY domains. Interaction between TRIM5α PRYSPRY domains and HIV-1 capsid core triggers the anti-HIV-1 activity of TRIM5α. Analysis of natural HIV variants and extensive mutational experiments has revealed the presence of critical amino acid residues in both the PRYSPRY domain and HIV capsid for potent HIV suppression by TRIM5α. Genetic manipulation of the human TRIM5 gene could establish human cells totally resistant to HIV-1, which may lead to a cure for HIV-1 infection in the future.
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McCarthy KR, Kirmaier A, Autissier P, Johnson WE. Evolutionary and Functional Analysis of Old World Primate TRIM5 Reveals the Ancient Emergence of Primate Lentiviruses and Convergent Evolution Targeting a Conserved Capsid Interface. PLoS Pathog 2015; 11:e1005085. [PMID: 26291613 PMCID: PMC4546234 DOI: 10.1371/journal.ppat.1005085] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 07/15/2015] [Indexed: 12/29/2022] Open
Abstract
The widespread distribution of lentiviruses among African primates, and the lack of severe pathogenesis in many of these natural reservoirs, are taken as evidence for long-term co-evolution between the simian immunodeficiency viruses (SIVs) and their primate hosts. Evidence for positive selection acting on antiviral restriction factors is consistent with virus-host interactions spanning millions of years of primate evolution. However, many restriction mechanisms are not virus-specific, and selection cannot be unambiguously attributed to any one type of virus. We hypothesized that the restriction factor TRIM5, because of its unique specificity for retrovirus capsids, should accumulate adaptive changes in a virus-specific fashion, and therefore, that phylogenetic reconstruction of TRIM5 evolution in African primates should reveal selection by lentiviruses closely related to modern SIVs. We analyzed complete TRIM5 coding sequences of 22 Old World primates and identified a tightly-spaced cluster of branch-specific adaptions appearing in the Cercopithecinae lineage after divergence from the Colobinae around 16 million years ago. Functional assays of both extant TRIM5 orthologs and reconstructed ancestral TRIM5 proteins revealed that this cluster of adaptations in TRIM5 specifically resulted in the ability to restrict Cercopithecine lentiviruses, but had no effect (positive or negative) on restriction of other retroviruses, including lentiviruses of non-Cercopithecine primates. The correlation between lineage-specific adaptations and ability to restrict viruses endemic to the same hosts supports the hypothesis that lentiviruses closely related to modern SIVs were present in Africa and infecting the ancestors of Cercopithecine primates as far back as 16 million years ago, and provides insight into the evolution of TRIM5 specificity. Old World primates in Africa are reservoir hosts for more than 40 species of simian immunodeficiency viruses (SIVs), including the sources of the human immunodeficiency viruses, HIV-1 and HIV-2. To investigate the prehistoric origins of these lentiviruses, we looked for patterns of evolution in the antiviral host gene TRIM5 that would reflect selection by lentiviruses during evolution of African primates. We identified a pattern of adaptive changes unique to the TRIM5 proteins of a subset of African monkeys that suggests that the ancestors of these viruses emerged between 11–16 million years ago, and by reconstructing and comparing the function of ancestral TRIM5 proteins with extant TRIM5 proteins, we confirmed that these adaptations confer specificity for their modern descendants, the SIVs.
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Affiliation(s)
- Kevin R. McCarthy
- Harvard Program in Virology, Harvard Medical School, Boston, Massachusetts, United States of America
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Andrea Kirmaier
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Patrick Autissier
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Welkin E. Johnson
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
- * E-mail:
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D'Cruz AA, Babon JJ, Norton RS, Nicola NA, Nicholson SE. Structure and function of the SPRY/B30.2 domain proteins involved in innate immunity. Protein Sci 2014; 22:1-10. [PMID: 23139046 DOI: 10.1002/pro.2185] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 10/16/2012] [Accepted: 10/19/2012] [Indexed: 11/12/2022]
Abstract
The SPRY domain is a protein interaction module found in 77 murine and ~100 human proteins, and is implicated in important biological pathways, including those that regulate innate and adaptive immunity. The current definition of the SPRY domain is based on a sequence repeat discovered in the splA kinase and ryanodine receptors. The greater SPRY family is divided into the B30.2 (which contains a PRY extension at the N-terminus) and "SPRY-only" sub-families. In this brief review, we examine the current structural and biochemical literature on SPRY/B30.2 domain involvement in key immune processes and highlight a PRY-like 60 amino acid region in the N-terminus of "SPRY-only" proteins. Phylogenetic, structural, and functional analyses suggest that this N-terminal region is related to the PRY region of B30.2 and should be characterized as part of an extended SPRY domain. Greater understanding of the functional importance of the N-terminal region in "SPRY only" proteins will enhance our ability to interrogate SPRY interactions with their respective binding partners.
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Affiliation(s)
- Akshay A D'Cruz
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
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Kelly JN, Barr SD. In silico analysis of functional single nucleotide polymorphisms in the human TRIM22 gene. PLoS One 2014; 9:e101436. [PMID: 24983760 PMCID: PMC4077803 DOI: 10.1371/journal.pone.0101436] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 06/06/2014] [Indexed: 01/18/2023] Open
Abstract
Tripartite motif protein 22 (TRIM22) is an evolutionarily ancient protein that plays an integral role in the host innate immune response to viruses. The antiviral TRIM22 protein has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 expression has also been associated with multiple sclerosis, cancer, and autoimmune disease. In this study, multiple in silico computational methods were used to identify non-synonymous or amino acid-changing SNPs (nsSNP) that are deleterious to TRIM22 structure and/or function. A sequence homology-based approach was adopted for screening nsSNPs in TRIM22, including six different in silico prediction algorithms and evolutionary conservation data from the ConSurf web server. In total, 14 high-risk nsSNPs were identified in TRIM22, most of which are located in a protein interaction module called the B30.2 domain. Additionally, 9 of the top high-risk nsSNPs altered the putative structure of TRIM22's B30.2 domain, particularly in the surface-exposed v2 and v3 regions. These same regions are critical for retroviral restriction by the closely-related TRIM5α protein. A number of putative structural and functional residues, including several sites that undergo post-translational modification, were also identified in TRIM22. This study is the first extensive in silico analysis of the highly polymorphic TRIM22 gene and will be a valuable resource for future targeted mechanistic and population-based studies.
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Affiliation(s)
- Jenna N. Kelly
- Western University, Schulich School of Medicine and Dentistry, Center for Human Immunology, Department of Microbiology and Immunology, Dental Sciences Building, London, Ontario, Canada
| | - Stephen D. Barr
- Western University, Schulich School of Medicine and Dentistry, Center for Human Immunology, Department of Microbiology and Immunology, Dental Sciences Building, London, Ontario, Canada
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Kelly JN, Woods MW, Xhiku S, Barr SD. Ancient and Recent Adaptive Evolution in the AntiviralTRIM22Gene: Identification of a Single-Nucleotide Polymorphism That Impacts TRIM22 Function. Hum Mutat 2014; 35:1072-81. [DOI: 10.1002/humu.22595] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 05/13/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Jenna N. Kelly
- Department of Microbiology and Immunology; Center for Human Immunology, Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
| | - Matthew W. Woods
- Department of Microbiology and Immunology; Center for Human Immunology, Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
| | - Sintia Xhiku
- Department of Microbiology and Immunology; Center for Human Immunology, Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
| | - Stephen D. Barr
- Department of Microbiology and Immunology; Center for Human Immunology, Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
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Nakayama EE, Shioda T. TRIM5α and Species Tropism of HIV/SIV. Front Microbiol 2012; 3:13. [PMID: 22291694 PMCID: PMC3264904 DOI: 10.3389/fmicb.2012.00013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 01/09/2012] [Indexed: 12/03/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) infects humans and chimpanzees but not old world monkeys (OWMs) such as the rhesus monkey (Rh) and cynomolgus monkey (CM). HIV-1 efficiently enters cells of OWMs but encounters a block before reverse transcription. This narrow host range is attributed to a barrier in the host cell. In 2004, the screening of a Rh cDNA library identified tripartite motif 5α (TRIM5α) as a cellular antiviral factor. TRIM5α is one of splicing variants produced by TRIM5 gene and TRIM5 proteins are members of the TRIM family containing RING, B-box 2, and coiled-coil domains. The RING domain is frequently found in E3 ubiquitin ligase and TRIM5α is degraded via the ubiquitin–proteasome-dependent pathway. Among TRIM5 splicing variants, TRIM5α alone has an additional C-terminal PRYSPRY (B30.2) domain. Previous studies have shown that sequence variation in variable regions of the PRYSPRY domain among different monkey species affects species-specific retrovirus infection, while amino acid sequence differences in the viral capsid protein determine viral sensitivity to restriction. TRIM5α recognizes the multimerized capsid proteins (viral core) of an incoming virus by its PRYSPRY domain and is thus believed to control retroviral infection. There are significant intraspecies variations in the Rh-TRIM5 gene. It has also been reported that some Rh and CM individuals have retrotransposed cyclophilin A open reading frame in the TRIM5 gene, which produces TRIM5–cyclophilin A fusion protein (TRIMCyp). TRIMCyp, which was originally identified as an anti-HIV-1 factor of New World owl monkeys, is an interesting example of the gain of a new function by retrotransposition. As different TRIM5 genotypes of Rh showed different levels of simian immunodeficiency virus replication in vivo, the TRIM5 genotyping is thought to be important in acquired immunodeficiency syndrome monkey models.
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Affiliation(s)
- Emi E Nakayama
- Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University Suita, Osaka, Japan
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Miyamoto T, Yokoyama M, Kono K, Shioda T, Sato H, Nakayama EE. A single amino acid of human immunodeficiency virus type 2 capsid protein affects conformation of two external loops and viral sensitivity to TRIM5α. PLoS One 2011; 6:e22779. [PMID: 21829511 PMCID: PMC3145752 DOI: 10.1371/journal.pone.0022779] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 07/07/2011] [Indexed: 11/18/2022] Open
Abstract
We previously reported that human immunodeficiency virus type 2 (HIV-2) carrying alanine or glutamine but not proline at position 120 of the capsid protein (CA) could grow in the presence of anti-viral factor TRIM5α of cynomolgus monkey (CM). To elucidate details of the interaction between the CA and TRIM5α, we generated mutant HIV-2 viruses, each carrying one of the remaining 17 possible amino acid residues, and examined their sensitivity to CM TRIM5α-mediated restriction. Results showed that hydrophobic residues or those with ring structures were associated with sensitivity, while those with small side chains or amide groups conferred resistance. Molecular dynamics simulation study revealed a structural basis for the differential TRIM5α sensitivities. The mutations at position 120 in the loop between helices 6 and 7 (L6/7) affected conformation of the neighboring loop between helices 4 and 5 (L4/5), and sensitive viruses had a common L4/5 conformation. In addition, the common L4/5 structures of the sensitive viruses were associated with a decreased probability of hydrogen bond formation between the 97th aspartic acid in L4/5 and the 119th arginine in L6/7. When we introduced aspartic acid-to-alanine substitution at position 97 (D97A) of the resistant virus carrying glutamine at position 120 to disrupt hydrogen bond formation, the resultant virus became moderately sensitive. Interestingly, the virus carrying glutamic acid at position 120 showed resistance, while its predicted L4/5 conformation was similar to those of sensitive viruses. The D97A substitution failed to alter the resistance of this particular virus, indicating that the 120th amino acid residue itself is also involved in sensitivity regardless of the L4/5 conformation. These results suggested that a hydrogen bond between the L4/5 and L6/7 modulates the overall structure of the exposed surface of the CA, but the amino acid residue at position 120 is also directly involved in CM TRIM5α recognition.
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Affiliation(s)
- Tadashi Miyamoto
- Department of Viral infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Masaru Yokoyama
- Pathogen Genomics Center, National Institute of Infectious Diseases, Musashi Murayama, Tokyo, Japan
| | - Ken Kono
- Department of Viral infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan
| | - Tatsuo Shioda
- Department of Viral infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Hironori Sato
- Pathogen Genomics Center, National Institute of Infectious Diseases, Musashi Murayama, Tokyo, Japan
| | - Emi E. Nakayama
- Department of Viral infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- * E-mail:
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Diaz-Griffero F, Gallo DE, Hope TJ, Sodroski J. Trafficking of some old world primate TRIM5α proteins through the nucleus. Retrovirology 2011; 8:38. [PMID: 21575157 PMCID: PMC3120760 DOI: 10.1186/1742-4690-8-38] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 05/15/2011] [Indexed: 01/15/2023] Open
Abstract
Background TRIM5α and TRIMCyp are cytoplasmic proteins that bind incoming retroviral capsids and mediate early blocks to viral infection. TRIM5 proteins form cytoplasmic bodies, which are highly dynamic structures. So far, TRIM5 proteins have been found only in the cytoplasm of cells. Interestingly, other proteins from the TRIM family localize to the nucleus. Therefore, we tested the possibility that TRIM5 proteins traffic to the nucleus and the impact of this trafficking on retroviral restriction. Results Here we report that the TRIM5α proteins of two Old World primates, humans and rhesus monkeys, are transported into the nucleus and are shuttled back to the cytoplasm by a leptomycin B-sensitive mechanism. In leptomycin B-treated cells, these TRIM5α proteins formed nuclear bodies that also contained TRIM19 (PML). Deletion of the amino terminus, including the linker 1 (L1) region, resulted in TRIM5α proteins that accumulated in nuclear bodies. Leptomycin B treatment of TRIM5α-expressing target cells only minimally affected the restriction of retrovirus infection. Conclusions We discovered the ability of human and rhesus TRIM5α to shuttle into and out of the nucleus. This novel trafficking ability of TRIM5α proteins could be important for an as-yet-unknown function of TRIM5α.
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Affiliation(s)
- Felipe Diaz-Griffero
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Kar AK, Mao Y, Bird G, Walensky L, Sodroski J. Characterization of a core fragment of the rhesus monkey TRIM5α protein. BMC BIOCHEMISTRY 2011; 12:1. [PMID: 21205312 PMCID: PMC3025952 DOI: 10.1186/1471-2091-12-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 01/04/2011] [Indexed: 11/13/2022]
Abstract
Background Like all tripartite motif (TRIM) proteins, the retroviral restriction factor TRIM5α consists of RING, B-box 2 and coiled-coil domains, with a C-terminal B30.2(SPRY) domain. Although structures have been determined for some individual TRIM domains, the structure of an intact TRIM protein is unknown. Results Here, we express and characterize a protease-resistant 29-kD core fragment containing the B-box 2, coiled coil and adjacent linker (L2) region of TRIM5α. This BCCL2 protein formed dimers and higher-order oligomers in solution. Approximately 40% of the BCCL2 secondary structure consisted of alpha helices. Partial loss of alpha-helical content and dissociation of dimers occurred at 42°C, with the residual alpha helices remaining stable up to 80°C. Conclusions These results indicate that the B-box 2, coiled-coil and linker 2 regions of TRIM5α form a core dimerization motif that exhibits a high level of alpha-helical content.
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Affiliation(s)
- Alak K Kar
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
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Kono K, Song H, Yokoyama M, Sato H, Shioda T, Nakayama EE. Multiple sites in the N-terminal half of simian immunodeficiency virus capsid protein contribute to evasion from rhesus monkey TRIM5α-mediated restriction. Retrovirology 2010; 7:72. [PMID: 20825647 PMCID: PMC2944288 DOI: 10.1186/1742-4690-7-72] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Accepted: 09/08/2010] [Indexed: 11/10/2022] Open
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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Affiliation(s)
- Ken Kono
- Department of Viral Infections, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan
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Abstract
Human immunodeficiency virus type 1 (HIV-1) shows a very narrow host range limited to humans and chimpanzees. Experimentally, HIV-1 does not infect Old World monkeys, such as rhesus (Rh) and cynomolgus (CM) monkeys, and fails to replicate in activated CD4 positive T lymphocytes obtained from these monkeys. In contrast, simian immunodeficiency virus isolated from a macaque monkey (SIVmac) can replicate well in both Rh and CM. In 2004, tripartite motif 5 alpha (TRIM5 alpha) was identified as a host factor which plays an important role in the restricted host range of HIV-1. Rh and CM TRIM5 alpha restrict HIV-1 infection but not SIVmac, while in comparison, anti-viral activity of human TRIM5 alpha against those viruses is very weak. TRIM5 alpha consists of the RING, B-box 2, coiled-coil and SPRY (B30.2) domains. The RING domain is frequently found in E3 ubiquitin ligase and TRIM5 alpha is degraded via the ubiquitin-proteasome pathway during HIV-1 restriction. TRIM5 alpha recognises the multimerised capsid (viral core) of an incoming virus by its alpha-isoform specific SPRY domain and is believed to be involved in innate immunity to control retroviral infection. Differences in amino acid sequences in the SPRY domain of TRIM5 alpha of different monkey species were found to affect species-specific restriction of retrovirus infection, while differences in amino acid sequences in the viral capsid protein determine viral sensitivity to restriction. Accurate structural analysis of the binding surface between the viral capsid protein and TRIM5 alpha SPRY is thus required for the development of new antiretroviral drugs that enhance anti-HIV-1 activity of human TRIM5 alpha.
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Affiliation(s)
- Emi E Nakayama
- Department of Viral Infections, Research Institute for Microbial Disease, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Impact of novel TRIM5alpha variants, Gly110Arg and G176del, on the anti-HIV-1 activity and the susceptibility to HIV-1 infection. AIDS 2009; 23:2091-100. [PMID: 19710594 DOI: 10.1097/qad.0b013e328331567a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE TRIM5alpha is one of the factors contributing to intracellular defense mechanisms against HIV-1 infection. We investigated the association of TRIM5alpha sequence variations with the susceptibility to HIV-1 infection in Japanese and Indian. DESIGN Sequence variations in TRIM5alpha were investigated in HIV-1-infected patients and ethnic-matched controls. Functional alterations caused by rare variants were analyzed. METHODS : We sequenced TRIM5alpha-exon 2 in both Japanese (94 HIV-1-infected patients and 487 controls) and Indian (101 HIV-1-infected patients and 99 controls). Frequency of variants and haplotypes were compared between the HIV-1-infected patients and controls. Functional analyses were performed for two rare variants, Gly110Arg and G176del. RESULTS The frequency of 43Tyr-allele in the Indian HIV-1-infected patients was significantly lower than that in the ethnic-matched controls (odds ratio = 0.52, 95% confidence interval = 0.31-0.89, P = 0.015). A similar tendency was observed in Japanese sample, although it was not statistically significant (odds ratio = 0.67, 95% confidence interval = 0.43-1.05, P = 0.095). On the other hand, haplotype analyses revealed that the haplotype carrying the 43Tyr-allele was significantly associated with the reduced susceptibility to HIV-1 infection in both ethnic groups. Functional analysis revealed that Gly110Arg variant weakened the anti-HIV-1 and anti-HIV-2 activities of human TRIM5alpha, whereas the truncated G176del-TRIM5 enhanced the antiviral activity of coexpressed TRIM5alpha. Epidemiological data were consistent in that Gly110Arg and G176del were associated with the susceptibility to and protection from HIV-1 infection, respectively. CONCLUSION Both common and rare variants of TRIM5alpha are associated with the susceptibility to HIV-1 infection.
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