Lionel Berthoux

Université du Québec à Trois-Rivières · Département de Biologie Medicale

The promyelocytic leukemia (PML) protein, a type I interferon (IFN-I)-induced gene product and a member of the tripartite motif (TRIM) family, modulates the transcriptional activity of viruses belonging to various families. Whether PML has an impact on the replication of HIV-1 has not been fully addressed, but recent studies point to its possible i...

About 35 million people worldwide were living with HIV-1 at the end of 2013 and over 25 million have already died of AIDS. AIDS patients show high variability in the speed of disease progression in the absence of treatment. While certain immunological traits have been shown to correlate with accelerated or slowed progression in some subjects, inclu...

Current HIV-1 gene therapy approaches aim at stopping the viral life cycle at its earliest steps, such as entry or immediate post-entry events. Among the most widely adopted strategies are CCR5 down-regulation/knockout and the use of broadly neutralizing antibodies. However, the long-term efficacy and side effects are still unclear. TRIM5α is an in...

TRIM5α from the rhesus macaque (TRIM5αRh) is a restriction factor that shows strong activity against HIV-1. TRIM5αRh binds specifically to HIV-1 capsid (CA) through its B30.2/PRYSPRY domain shortly after entry of the virus into the cytoplasm. Recently, three putative SUMO interacting motifs (SIMs) have been identified in the PRYSPRY domain of human...

Unlabelled: The tripartite motif (TRIM) family of proteins includes the TRIM5α antiretroviral restriction factor. TRIM5α from many Old World and some New World monkeys can restrict the human immunodeficiency virus type 1 (HIV-1), while human TRIM5α restricts N-tropic murine leukemia virus (N-MLV). TRIM5α forms highly dynamic cytoplasmic bodies (CB...

Human MURFs (muscle-specific RING finger) are members of the TRIM (tripartite motif) family of proteins characterized by their COS (C-terminal subgroup one signature) domain. MURFs play a role in sarcomere formation and microtubule dynamics. It was previously established that some TRIMs undergo post-translational modification by SUMO. In this study...

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19. Though many COVID-19 vaccines have been developed, most of them are delivered via intramuscular injection and thus confer relatively weak mucosal immunity against the natural infection. Virus-Like Particles (VLPs) are self-assembled nanostructures compo...

Major threats to the human lifespan include cancer, infectious diseases, diabetes, mental degenerative conditions and also reduced agricultural productivity due to climate changes, together with new and more devastating plant diseases. From all of this, the need arises to find new biopesticides and new medicines. Plants and microorganisms are the m...

Résumé - Les virus à ARN sont la classe d’agents pathogènes la plus souvent responsable de l’apparition de nouvelles maladies humaines, avec un taux de deux à trois virus nouvellement identifiés annuellement. La récente pandémie de maladie à coronavirus 2019 (Covid-19) souligne l’importance de la découverte de nouveaux agents antiviraux efficaces....

Amaryllidaceae alkaloids (AAs) are a structurally diverse family of alkaloids recognized for their many therapeutic properties, such as antiviral, anti-cholinesterase, and anticancer properties. Norbelladine and its derivatives, whose biological properties are poorly studied, are key intermediates required for the biosynthesis of all ~650 reported...

Ten Amaryllidaceae alkaloids (AAs) were isolated for the first time from Pancratium maritimum collected in Calabria region, Italy. They belong to different subgroups of this family and were identified as lycorine, which is the main alkaloid, 9-O-demethyllycorine, haemanthidine, haemanthamine, 11-hydroxyvittatine, homolycorine, pancracine, obliquine...

Amaryllidaceae plants are rich in alkaloids with biological properties. Pancratium trian-thum is an Amaryllidaceae species widely used in African folk medicine to treat several diseases such as central nervous system disorders, tumors, and microbial infections, and it is used to heal wounds. The current investigation explored the biological propert...

Dengue fever, caused by dengue virus (DENV) is the most prevalent arthropod-borne viral disease, and is endemic in many tropical and sub-tropical parts of the world with an increasing incidence in temperate regions. The closely related flavivirus Zika virus (ZIKV) can be transmitted vertically in utero and causes congenital Zika syndrome and other...

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monit...

the PDF can be download freely on pubmed. https://pubmed.ncbi.nlm.nih.gov/33634751/

Tripartite-motif-containing protein 5 isoform α (TRIM5α) is a cytoplasmic antiretroviral effector upregulated by type I interferons (IFN-I). We previously showed that two points mutations, R332G/R335G, in the retroviral capsid-binding region confer human TRIM5α the capacity to target and strongly restrict HIV-1 upon overexpression of the mutated pr...

TRIM5α is a cytoplasmic antiretroviral effector upregulated by type I interferons (IFN-I). We previously showed that two points mutations, R332G/R335G, in the retroviral capsid-binding region confer human TRIM5α the capacity to target and strongly restrict HIV-1 upon over-expression of the mutated protein. Here, we used CRISPR-Cas9-mediated homolog...

In this review, we summarize recent advances in the knowledge of the biological functions of human TRIM5α, a cytoplasmic protein mostly known for its antiretroviral functions. In addition to directly targeting retroviral capsid cores, an inhibitory activity called "restriction", TRIM5α senses retroviruses and activates NF-κB and AP-1 signaling path...

TRIM5α is a cytoplasmic antiviral effector induced by type I interferons (IFN-I) that has the potential to intercept incoming retroviruses by interacting with their capsid core, leading to uncoating induction and the partial degradation of core components. Most HIV-1 strains escape restriction by human TRIM5α due to a lack of interaction between TR...

Flaviviruses are a genus of mostly arthropod-borne RNA viruses that cause a range of pathologies in humans. Basic knowledge on flaviviruses is rapidly expanding, partly due to their status as frequent emerging or re-emerging pathogens. Flaviviruses include the dengue, Zika, West Nile, tick-borne encephalitis and yellow fever viruses (DENV, ZIKV, WN...

Elite controllers (ECs) are a rare subset of HIV-1 slow progressors characterized by prolonged viremia suppression. HLA alleles B27 and B57 promote the cytotoxic T lymphocyte (CTL)-mediated depletion of infected cells in ECs, leading to the emergence of escape mutations in the viral capsid (CA). Whether those mutations modulate CA detection by inna...

CA N-terminal amino acid sequences from clinical isolates. (PDF)

CA polymorphisms and associated functions in published reports. (PDF)

Oligodeoxynucleotide (ODN) primers used for Gag amplification and cloning. (PDF)

ODN primers used for Real-Time qPCR. (PDF)

References for supplementary tables. (PDF)

TRIM5α and Mx2 knockdown validation. (a) mRNA levels were determined by RT-qPCR and normalized on GAPDH mRNA levels. Shown are mean mRNA levels calculated by RT-qPCR performed in duplicates on total RNA extracted from IFN-β-treated Jurkat cells, and normalized to the shLuc control. (b) Same analysis in THP-1 cells. (PDF)

CRISPR/Cas9-mediated editing of TRIM5α in human cell lines. (a) Cas9 was targeted to exon 1 of the TRIM5 gene (green) by two selected gRNAs, whose binding sites are schematized with scissors. Arrowheads indicate the positions of the binding sites for the ODNs used in the PCR-Surveyor assay. (b) Surveyor assay. Briefly, PCR products amplified from 2...

ODN primers used to construct vectors for the expression of gRNAs and shRNAs. (PDF)

Patient characteristics. (a) CD4+ T cell counts, (b) viremia, at the time-points used in this study and according to their HLA type. B27 or B57 are grouped together. (c) Evolution of CD4, CD8 and virus counts for EC9. The black arrow indicates the time-point used in this study. The red line shows initiation and continuation of antiretroviral therap...

HLA status and presence of mutations known to modulate restriction by Mx2 and TRIM5α. (a) Bar graph of the contingency table of mutations at the G116 position (Mx2) in individuals bearing B27/B57 or other alleles (Chi-square test; p = 0.0169). (b) Bar graphs showing the presence or the absence of mutations previously shown to be associated with TRI...

Productively infected cells in microscopy experiments. (a) Microscopy images corresponding to Fig 6A with the GFP field included. (b) Frequency of infected (GFP+) cells quantified by analyzing ≥100 cells from ≥ 10 pictures and plotted according to TRIM5α expression and viral infection. The Kruskal-Wallis test and the Dunn's Multiple Comparison Test...

Hypothetical model. Following entry, viruses from a B27/B57+ subject escape Mx2 restriction but are recognized by TRIM5α. TRIM5α disrupts the proper uncoating process and may trigger pro-inflammatory signals through Ubc13- and TAK1-dependent signaling. In THP-1 cells, this leads to activation of NF-κB and AP-1 and production of type I IFN productio...

Sensitivity of NRC10GFP and NL43GFP to restriction by Mx2 and TRIM5α. Jurkat cells knocked down for Mx2 or TRIM5α or both were infected with increasing amounts of the two HIV-1vectors. Infectivity was measured by FACS as the % of GFP+ cells 48 h post-infection. (PDF)

Effect of inhibitors on HIV-1 vector infectivity. THP-1 cells were pre-treated or not with (a) BX795 (iTBK1), (b) BAY11-7085 (iNF-κB) or (c) SP600125 (iAP-1) for 1 h, infected with DsRed-expressing chimeric vectors (“virus 1”), and 48 h later infected with NRC1GFP (“virus 2”). Infectivity of DsRed-virus 1 was assessed by flow cytometry 48 h later....

The type I interferon (IFN-I)-inducible human restriction factor TRIM5α inhibits the infection of human cells by specific nonhuman retroviruses, such as N-MLV and EIAV, but does not generally target HIV-1. However, the introduction of two aminoacid substitutions, R332G and R355G, in the human TRIM5α (huTRIM5α) domain responsible for retroviral caps...

In general viruses' modus operandi to propagate is achieved by the co-opting host cell components, membranes, proteins, and machineries to their advantage. This is true for virtually every aspect of a virus' replication cycle from virus entry to the budding or release of progeny virus particles. In this chapter, we will discuss new information on t...

The type I interferon (IFN-I)-inducible human restriction factor TRIM5α inhibits the infection of human cells by specific nonhuman retroviruses, such as N-MLV and EIAV, but does not generally target HIV-1. However, the introduction of two aminoacid substitutions, R332G and R355G, in the human TRIM5α (huTRIM5α) domain responsible for retroviral caps...

PML is involved in innate immune mechanisms against both DNA and RNA viruses. Although the mechanism by which PML inhibits highly divergent viruses is unclear, it was recently found that it can increase the transcription of interferon-stimulated genes (ISGs). However, whether human PML inhibits HIV-1 has been debated. Here we provide unambiguous, k...

The PML (promyelocytic leukemia) protein is a member of the TRIM family, a large group of proteins that show high diversity in functions but possess a common tripartite motif giving the family its name. We and others recently reported that both murine PML (mPML) and human PML (hPML) strongly restrict the early stages of infection by HIV-1 and other...

The PML (promyelocytic leukemia) protein is a member of the TRIM family, a large group of proteins that show high diversity in functions but possess a common tripartite motif giving the family its name. We and others recently reported that both murine PML (mPML) and human PML (hPML) strongly restrict the early stages of infection by HIV-1 and other...

HIV-2 and SIVMAC are AIDS-causing, zoonotic lentiviruses that jumped to humans and rhesus macaques, respectively, from SIVSM-bearing sooty mangabey monkeys. Cross-species transmission events such as these sometimes necessitate virus adaptation to species-specific, host restriction factors such as TRIM5. Here, a new human restriction activity is des...

Interferon-induced restriction factors can significantly affect the replicative capacity of retroviruses in mammals. Tripartite motif protein 5, isoform α (TRIM5α) is a restriction factor that acts at early stages of the virus life cycle by intercepting and destabilizing incoming retroviral cores. Sensitivity to TRIM5α maps to the N-terminal domain...

Retroviral capsid (CA) cores undergo uncoating during their retrograde transport (toward the nucleus), and/or after reaching the nuclear membrane. However, whether HIV-1 CA core uncoating is dependent upon its transport is not understood. There is some evidence that HIV-1 cores retrograde transport involves cytoplasmic dynein complexes translocatin...

TRIM5α is a type I interferon-stimulated anti-retroviral restriction factor expressed in most primates and homologous proteins are expressed in other mammals. Through its C-terminal PRYSPRY (B30.2) domain, TRIM5α binds to incoming and intact post-fusion retroviral cores in the cytoplasm. Following this direct interaction, the retroviral capsid core...

SIVSM is a lentivirus endemic to the West African sooty mangabey (Cercocebus atys). HIV-2 and SIVMAC are zoonoses that resulted from SIVSM transmission to humans and Asian rhesus macaques (Macaca mulatto), respectively. Human leukemia cell lines, human peripheral blood mononuclear cells and CD4+ T cells, were 4 to 50-fold less permissive for SIVMAC...

Background HIV-1 is inhibited early after entry into cells expressing some simian orthologues of the tripartite motif protein family member TRIM5α. Mutants of the human orthologue (TRIM5αhu) can also provide protection against HIV-1. The host protein cyclophilin A (CypA) binds incoming HIV-1 capsid (CA) proteins and enhances early stages of HIV-1 r...

shows knockdown of CypA in TE671 and in Sup-T1 cells. Figure S2 shows the effects of V86M and of CsA on the restriction of HIV-1 by additional mutants of TRIM5αhu.

Sumoylation modulates many proteins implicated in apoptosis such as Fas, TNFR1, Daxx, p53 and its regulator MDM2. Some of these proteins, such as DRP-1, are involved in the intrinsic apoptosis pathway. The intrinsic pathway is regulated at the mitochondrial level by the Bcl-2 family of proteins. The small-molecule inhibitor BH3I-2' binds to the hyd...

Human-derived antiretroviral transgenes are of great biomedical interest and are actively pursued. HIV-1 is efficiently inhibited at post-entry, pre-integration replication stages by point mutations in the variable region 1 (v1) of the human restriction factor TRIM5α. Here we use a mutated megaprimer approach to create a mutant library of TRIM5αHu...

In human cells, endogenous TRIM5alpha strongly inhibits N-tropic strains of murine leukemia virus (N-MLV) but does not target the closely related B-MLV. We have used a shRNA-based loss-of-function screen to isolate factors other than TRIM5alpha involved in the restriction of N-MLV. In one of the isolated clones, the shRNA expressed was found to tar...

Rhesus macaque tripartite motif (TRIM)5alpha potently inhibits early stages of human immunodeficiency virus (HIV)-1 replication, while the human orthologue has little effect on this virus. We used PCR-based random mutagenesis to construct a large library of human TRIM5alpha variants containing mutations in the PRYSPRY domain. We then applied a func...

Proteins of the TRIM5 family, such as TRIM5alpha and the related TRIMCyp, are cytoplasmic factors that can inhibit incoming retroviruses. This type of restriction requires a direct interaction between TRIM5 proteins and capsid proteins that are part of mature, intact retroviral cores. In such cores, capsids are arranged as hexameric units. Multiple...

Retroviral DNA integration leaves behind a single-strand DNA discontinuity at each virus:host DNA junction. It has long been proposed that cellular proteins detect and repair the integrated DNA and that failure to do so might lead to apoptotic cell death, but their identity remains unknown. PIKK family members ATM, DNA-PKcs and ATR have all been pr...

HIV-1 integrase (IN) catalyzes biochemical reactions required for viral cDNA insertion into host cell chromosomal DNA, an essential step in the HIV-1 replication cycle. In one of these reactions, the two ends of the linear viral cDNA are believed to be simultaneously ligated to chromosomal DNA by a tetrameric form of IN. The structure of the full-l...

TRIM5alpha, which is expressed in most primates and the related TRIMCyp, which has been found in one of the New World monkey species, are antiviral proteins of the TRIM5 family that are able to intercept incoming retroviruses early after their entry into cells. The mechanism of action has been partially elucidated for TRIM5alpha, which seems to pro...

Lentiviral vectors derived from the human immunodeficiency virus-1 (HIV-1) have a higher propensity to transduce nondividing cells compared to vectors based on oncoretroviruses. We report here that genistein, a previously known protein tyrosine kinase (PTK) inhibitor and G2 cell cycle arrest inducer, significantly enhanced lentiviral transduction i...

Cyclophilin A (CypA), a cytoplasmic, human immunodeficiency virus type 1 (HIV-1) CA-binding protein, acts after virion membrane fusion with human cells to increase HIV-1 infectivity. HIV-1 CA is similarly greeted by CypA soon after entry into rhesus macaque or African green monkey cells, where, paradoxically, the interaction decreases HIV-1 infecti...

The peptidyl-prolyl isomerase cyclophilin A (CypA) embraces an exposed, proline-rich loop on HIV-1 capsid (CA) and renders reverse transcription complexes resistant to an antiviral activity in human cells. A CypA fusion with TRIM5 that is unique to New World owl monkeys also targets HIV-1 CA, but this interaction potently inhibits infection. A simi...

TRIM5 is a determinant of species-specific differences in susceptibility to infection by retroviruses bearing particular capsids. Human immunodeficiency virus type 1 (HIV-1) infection is blocked by the alpha isoform of macaque TRIM5 (TRIM5αrh) or by the product of the owl monkey TRIM5-cyclophilin A gene fusion (TRIMCyp). Human TRIM5α potently restr...

Molecular Therapy (2005) 11, S1|[ndash]|S1; doi: 10.1016/j.ymthe.2005.06.005 2. Cellular Mechanisms Involved with Lentiviral Gene Transfer Shangming Zhang1, Karen Pollok2, Lakshmi Sastry1, Lionel Berthoux3, Jeremy Luban3 and Kenneth Cornetta11Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN2The Herman B Wells...

The p6 domain of the human immunodeficiency virus type 1 (HIV-1) Gag polyprotein mediates virion budding from infected cells via protein-protein contacts with the class E vacuolar protein sorting factors, Tsg101 and AIP1/ALIX. Interaction with Tsg101 is strengthened by covalent attachment of monovalent ubiquitin to HIV-1 p6. To identify additional...

Human immunodeficiency virus type 1 (HIV-1) cDNA synthesis is inhibited in cells from some nonhuman primates by an activity called Lv1. Sensitivity to restriction by Lv1 maps to a region of the HIV-1 CA required for interaction with the cellular protein cyclophilin A. A similar antiviral activity in mammalian cells, Ref1, inhibits reverse transcrip...

In Old World primates, TRIM5-alpha confers a potent block to human immunodeficiency virus type 1 (HIV-1) infection that acts after virus entry into cells. Cyclophilin A (CypA) binding to viral capsid protects HIV-1 from a similar activity in human cells. Among New World primates, only owl monkeys exhibit post-entry restriction of HIV-1 (ref. 1). Pa...

The fate of transplanted chondrocytes used to elicit the repair of osteochondral defects is unknown. The objective of this study was to examine the fate and the expression of cartilage-specific genes in chondrocytes when the chondrocyte phenotype was maintained preoperatively by alginate suspension culture, the cells were labeled with enhanced gree...

In this study the authors explored the feasibility of using transduced cells for gene therapy to induce healing of osteochondral defects. Both a mouse mesenchymal cell line and mixed rabbit adherent stromal cells were transduced with either liposomal transfection or retroviral transduction using a traceable gene. Transduction efficiency was more th...

Potent drugs such as cyclosporine have provided effective probes of signal transduction pathways and, as well, of human immunodeficiency virus type 1 (HIV-1) replication mechanisms. Recently, it was reported that As2O3, a drug used to treat acute promyelocytic leukemia (PML), stimulates HIV-1 replication. We found that As2O3 accelerates the kinetic...

The molecular mechanisms that regulate the proliferation of smooth muscle cells (SMCs) of the vasculature in response to injury are poorly understood. Members of the inhibitor of DNA binding (Id) class of helix-loop-helix transcription factors are known to regulate the growth of a variety of cell types; however, the expression of the various Id gen...