1
|
Kemeter LM, Birzer A, Heym S, Thoma-Kress AK. Milk Transmission of Mammalian Retroviruses. Microorganisms 2023; 11:1777. [PMID: 37512949 PMCID: PMC10386362 DOI: 10.3390/microorganisms11071777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/02/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
The transmission of viruses from one host to another typically occurs through horizontal or vertical pathways. The horizontal pathways include transmission amongst individuals, usually through bodily fluids or excretions, while vertical transmission transpires from mother to their offspring, either during pregnancy, childbirth, or breastfeeding. While there are more than 200 human pathogenic viruses to date, only a small number of them are known to be transmitted via breast milk, including cytomegalovirus (CMV), human immunodeficiency virus type 1 (HIV-1), and human T cell lymphotropic virus type 1 (HTLV-1), the latter two belonging to the family Retroviridae. Breast milk transmission is a common characteristic among mammalian retroviruses, but there is a lack of reports summarizing our knowledge regarding this route of transmission of mammalian retroviruses. Here, we provide an overview of the transmission of mammalian exogenous retroviruses with a focus on Orthoretrovirinae, and we highlight whether they have been described or suspected to be transmitted through breast milk, covering various species. We also elaborate on the production and composition of breast milk and discuss potential entry sites of exogenous mammalian retroviruses during oral transmission.
Collapse
Affiliation(s)
- Laura M Kemeter
- Institute of Clinical and Molecular Virology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Alexandra Birzer
- Institute of Clinical and Molecular Virology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Stefanie Heym
- Institute of Clinical and Molecular Virology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Andrea K Thoma-Kress
- Institute of Clinical and Molecular Virology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| |
Collapse
|
2
|
Saied AA, Metwally AA, Mohamed HMA, Haridy MAM. The contribution of bovines to human health against viral infections. Environ Sci Pollut Res Int 2021; 28:46999-47023. [PMID: 34272669 PMCID: PMC8284698 DOI: 10.1007/s11356-021-14941-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/12/2021] [Indexed: 04/12/2023]
Abstract
In the last 40 years, novel viruses have evolved at a much faster pace than other pathogens. Viral diseases pose a significant threat to public health around the world. Bovines have a longstanding history of significant contributions to human nutrition, agricultural, industrial purposes, medical research, drug and vaccine development, and livelihood. The life cycle, genomic structures, viral proteins, and pathophysiology of bovine viruses studied in vitro paved the way for understanding the human counterparts. Calf model has been used for testing vaccines against RSV, papillomavirus vaccines and anti-HCV agents were principally developed after using the BPV and BVDV model, respectively. Some bovine viruses-based vaccines (BPIV-3 and bovine rotaviruses) were successfully developed, clinically tried, and commercially produced. Cows, immunized with HIV envelope glycoprotein, produced effective broadly neutralizing antibodies in their serum and colostrum against HIV. Here, we have summarized a few examples of human viral infections for which the use of bovines has contributed to the acquisition of new knowledge to improve human health against viral infections covering the convergence between some human and bovine viruses and using bovines as disease models. Additionally, the production of vaccines and drugs, bovine-based products were covered, and the precautions in dealing with bovines and bovine-based materials.
Collapse
Affiliation(s)
- AbdulRahman A Saied
- Department of Food Establishments Licensing (Aswan Branch), National Food Safety Authority (NFSA), Aswan, 81511, Egypt.
- Touristic Activities and Interior Offices Sector (Aswan Office), Ministry of Tourism and Antiquities, Aswan, 81511, Egypt.
| | - Asmaa A Metwally
- Department of Surgery, Anesthesiology, and Radiology, Faculty of Veterinary Medicine, Aswan University, Aswan, 81511, Egypt
| | - Hams M A Mohamed
- Department of Microbiology, Faculty of Veterinary Medicine, South Valley University, Qena, 83523, Egypt
| | - Mohie A M Haridy
- Department of Pathology and Clinical Pathology, Faculty of Veterinary Medicine, South Valley University, Qena, 83523, Egypt.
| |
Collapse
|
3
|
González-Fernández VD, Tórtora Pérez JL, García Flores MM, Aguilar Setién JÁ, Ramírez Álvarez H. First evidence of bovine immunodeficiency virus infection in Mexican cattle. Transbound Emerg Dis 2020; 67:1768-1775. [PMID: 32129921 DOI: 10.1111/tbed.13530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 02/21/2020] [Accepted: 02/26/2020] [Indexed: 02/05/2023]
Abstract
This study set out to identify the presence of bovine immunodeficiency virus (BIV) in animals geographically located in Mexico. BIV was first discovered in the United States in a dairy cow with persistent lymphocytosis, lymphoid hyperplasia and lymphocytic encephalitis. Many studies indicate that BIV infection is globally distributed, but its presence in Mexico remains unknown. We collected 1,168 heparinized blood samples from cattle in ten states across the Mexican Republic, then separated plasma using centrifugation and tested for antibodies against BIV. We used an indirect ELISA based on the use of a synthetic peptide derived from transmembrane glycoprotein (gp45/TM). In order to identify the viral genome, we designed a synthetic gene as a PCR control, as well as a pair of oligonucleotides for amplifying a 519 bp product of the env gene which encodes the surface protein. Positive amplicons were purified and subjected to nucleotide sequencing. A total of 189 (28.94%) tested plasma samples suggest the presence of specific anti-BIV antibodies in all states studied except for Chiapas. Additionally, PCR results identified six positive cows in the states of Puebla and Coahuila. BIV in these cows was confirmed via nucleotide sequencing and in silico analysis of these samples. This is the first report of the presence of BIV in Mexican cattle.
Collapse
Affiliation(s)
- Víctor David González-Fernández
- Virology, Genetics and Molecular Biology Laboratory, Faculty of Higher Education, Cuautitlan, Veterinary Medicine, National Autonomous University of Mexico, Cuautitlán Izcalli, Mexico
| | - Jorge Luis Tórtora Pérez
- Virology, Genetics and Molecular Biology Laboratory, Faculty of Higher Education, Cuautitlan, Veterinary Medicine, National Autonomous University of Mexico, Cuautitlán Izcalli, Mexico
| | - María Martha García Flores
- Laboratory of Immunovirology, Medical Research in Immunology Unit, Pediatric Hospital, National Medical Center XXI Century, Mexican Institute of Social Security, Mexico City, Mexico
| | - José Álvaro Aguilar Setién
- Laboratory of Immunovirology, Medical Research in Immunology Unit, Pediatric Hospital, National Medical Center XXI Century, Mexican Institute of Social Security, Mexico City, Mexico
| | - Hugo Ramírez Álvarez
- Virology, Genetics and Molecular Biology Laboratory, Faculty of Higher Education, Cuautitlan, Veterinary Medicine, National Autonomous University of Mexico, Cuautitlán Izcalli, Mexico
| |
Collapse
|
4
|
Wang C, Zhang K, Meng L, Zhang X, Song Y, Zhang Y, Gai Y, Zhang Y, Yu B, Wu J, Wang S, Yu X. The C-terminal domain of feline and bovine SAMHD1 proteins has a crucial role in lentiviral restriction. J Biol Chem 2020; 295:4252-4264. [PMID: 32075911 PMCID: PMC7105322 DOI: 10.1074/jbc.ra120.012767] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/14/2020] [Indexed: 01/29/2023] Open
Abstract
SAM and HD domain-containing protein 1 (SAMHD1) is a host factor that restricts reverse transcription of lentiviruses such as HIV in myeloid cells and resting T cells through its dNTP triphosphohydrolase (dNTPase) activity. Lentiviruses counteract this restriction by expressing the accessory protein Vpx or Vpr, which targets SAMHD1 for proteasomal degradation. SAMHD1 is conserved among mammals, and the feline and bovine SAMHD1 proteins (fSAM and bSAM) restrict lentiviruses by reducing cellular dNTP concentrations. However, the functional regions of fSAM and bSAM that are required for their biological functions are not well-characterized. Here, to establish alternative models to investigate SAMHD1 in vivo, we studied the restriction profile of fSAM and bSAM against different primate lentiviruses. We found that both fSAM and bSAM strongly restrict primate lentiviruses and that Vpx induces the proteasomal degradation of both fSAM and bSAM. Further investigation identified one and five amino acid sites in the C-terminal domain (CTD) of fSAM and bSAM, respectively, that are required for Vpx-mediated degradation. We also found that the CTD of bSAM is directly involved in mediating bSAM's antiviral activity by regulating dNTPase activity, whereas the CTD of fSAM is not. Our results suggest that the CTDs of fSAM and bSAM have important roles in their antiviral functions. These findings advance our understanding of the mechanism of fSAM- and bSAM-mediated viral restriction and might inform strategies for improving HIV animal models.
Collapse
Affiliation(s)
- Chu Wang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China; The First Hospital and Institute of Immunology, Jilin University, Changchun 130012, China
| | - Kaikai Zhang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Lina Meng
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Xin Zhang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Yanan Song
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Ying Zhang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Yanxin Gai
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Yuepeng Zhang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Bin Yu
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China; Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Jiaxin Wu
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China; Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Song Wang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130012, China
| | - Xianghui Yu
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China; Key Laboratory for Molecular Enzymology and Engineering, the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China.
| |
Collapse
|
5
|
Ali AF, Selim A, Manaa EA, Abdelrahman A, Sakr A. Oxidative state markers and clinicopathological findings associated with bovine leukemia virus infection in cattle. Microb Pathog 2019; 136:103662. [PMID: 31400442 DOI: 10.1016/j.micpath.2019.103662] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 08/07/2019] [Accepted: 08/07/2019] [Indexed: 12/29/2022]
Abstract
The aim of present study was to investigate hematological, biochemical and oxidative state parameters in cattle spontaneously infected with bovine leukemia virus (BLV). A total 500 cattle were examined for BLV infection by enzyme linked immunosorbent assay (ELISA). Eighty (16%) animals were positive for BLV infection. Biochemical and oxidative stress markers revealed significant increases in liver enzymes Alanine Transaminase, Aspartate Transaminase and Alkaline Phosphatase (ALT, AST and ALP) activities, creatinine level and superoxide dismutase (SOD) activity associated with a significant decrease in calcium level in seropositive cattle in comparison with seronegative cattle. Meanwhile, non-significant changes were reported in levels of malondialdehyde (MDA), Nitric oxide (NO), reduced glutathione (GSH) and hematological parameters in seropositive cattle in comparison with seronegative cattle.
Collapse
|
6
|
Peterson TA, MacLean AG. Current and Future Therapeutic Strategies for Lentiviral Eradication from Macrophage Reservoirs. J Neuroimmune Pharmacol 2018; 14:68-93. [PMID: 30317409 DOI: 10.1007/s11481-018-9814-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 10/02/2018] [Indexed: 12/17/2022]
Abstract
Macrophages, one of the most abundant populations of leukocytes in the body, function as the first line of defense against pathogen invaders. Human Immunodeficiency virus 1 (HIV-1) remains to date one of the most extensively studied viral infections. Naturally occurring lentiviruses in domestic and primate species serve as valuable models to investigate lentiviral pathogenesis and novel therapeutics. Better understanding of the role macrophages play in HIV pathogenesis will aid in the advancement towards a cure. Even with current efficacy of first- and second-line Antiretroviral Therapy (ART) guidelines and future efficacy of Long Acting Slow Effective Release-ART (LASER-ART); ART alone does not lead to a cure. The major challenge of HIV eradication is viral latency. Latency Reversal Agents (LRAs) show promise as a possible means to eradicate HIV-1 from the body. It has become evident that complete eradication will need to include combinations of various effective therapeutic strategies such as LASER-ART, LRAs, and gene editing. Review of the current literature indicates the most promising HIV eradication strategy appears to be LASER-ART in conjunction with viral and receptor gene modifications via the CRISPR/Cas9 system. Graphical abstract A multimodal approach to HIV treatment including gene editing, LASER-ART, and latency reversal agents may provide a means to achieve HIV eradication.
Collapse
Affiliation(s)
- Tiffany A Peterson
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - Andrew G MacLean
- Department of Microbiology & Immunology, Division of Comparative Pathology, Tulane National Primate Research Center, Tulane Center for Aging, Tulane Brain Institute, 18703 Three Rivers Road, Covington, LA, 70433, USA.
| |
Collapse
|
7
|
Mereby SA, Maehigashi T, Holler JM, Kim DH, Schinazi RF, Kim B. Interplay of ancestral non-primate lentiviruses with the virus-restricting SAMHD1 proteins of their hosts. J Biol Chem 2018; 293:16402-16412. [PMID: 30181218 PMCID: PMC6200947 DOI: 10.1074/jbc.ra118.004567] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/29/2018] [Indexed: 11/26/2022] Open
Abstract
Lentiviruses infect both dividing CD4+ T cells and nondividing myeloid cells, and the infected myeloid cells serve as long-living viral reservoirs. Host sterile alpha motif– and histidine-aspartate domain–containing protein 1 (SAMHD1) kinetically restricts reverse transcription of primate lentiviruses, including human immunodeficiency virus, type 1 (HIV-1) and simian immunodeficiency virus (SIV), in nondividing myeloid cells. SAMHD1 enforces this restriction through its dNTP triphosphohydrolase (dNTPase) activity that depletes cellular dNTPs. Some primate lentiviruses, such as HIV-2, SIVsm, and SIVagm, counteract SAMHD1 restriction by using their viral accessory proteins (Vpx or Vpr) that induce the proteosomal degradation of SAMHD1 and increase dNTP levels. SAMHD1 is conserved among non-primate mammals such as cats, cows, and horses that also carry their own lentiviruses (feline and bovine immunodeficiency viruses and equine infectious anemia viruses, respectively). However, whether these viruses also target SAMHD1 is unknown. Here, we tested whether these ancestral non-primate lentiviruses also can counteract their host SAMHD1 proteins by promoting their proteosomal degradation. Using biochemical and various cell-based assays, we observed that SAMHD1 proteins from the non-primate host species display dGTP-dependent dNTPase activity, but that the non-primate lentiviruses fail to proteosomally degrade the SAMHD1 proteins of their hosts. Our findings suggest that accessory protein–mediated proteosomal degradation of SAMHD1 did not exist among the ancestral non-primate lentiviruses and was uniquely gained by some primate lentiviruses after their transmission to primate species.
Collapse
Affiliation(s)
- Sarah A Mereby
- From the Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Tatsuya Maehigashi
- From the Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Jessica M Holler
- From the Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Dong-Hyun Kim
- Department of Pharmacy, Kyung-Hee University, Seoul 130-701, South Korea, and
| | - Raymond F Schinazi
- From the Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Baek Kim
- From the Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322, .,Department of Pharmacy, Kyung-Hee University, Seoul 130-701, South Korea, and.,Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, Georgia 30322
| |
Collapse
|
8
|
de Pablo-Maiso L, Doménech A, Echeverría I, Gómez-Arrebola C, de Andrés D, Rosati S, Gómez-Lucia E, Reina R. Prospects in Innate Immune Responses as Potential Control Strategies against Non-Primate Lentiviruses. Viruses 2018; 10:v10080435. [PMID: 30126090 PMCID: PMC6116218 DOI: 10.3390/v10080435] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/08/2018] [Accepted: 08/10/2018] [Indexed: 02/06/2023] Open
Abstract
Lentiviruses are infectious agents of a number of animal species, including sheep, goats, horses, monkeys, cows, and cats, in addition to humans. As in the human case, the host immune response fails to control the establishment of chronic persistent infection that finally leads to a specific disease development. Despite intensive research on the development of lentivirus vaccines, it is still not clear which immune responses can protect against infection. Viral mutations resulting in escape from T-cell or antibody-mediated responses are the basis of the immune failure to control the infection. The innate immune response provides the first line of defense against viral infections in an antigen-independent manner. Antiviral innate responses are conducted by dendritic cells, macrophages, and natural killer cells, often targeted by lentiviruses, and intrinsic antiviral mechanisms exerted by all cells. Intrinsic responses depend on the recognition of the viral pathogen-associated molecular patterns (PAMPs) by pathogen recognition receptors (PRRs), and the signaling cascades leading to an antiviral state by inducing the expression of antiviral proteins, including restriction factors. This review describes the latest advances on innate immunity related to the infection by animal lentiviruses, centered on small ruminant lentiviruses (SRLV), equine infectious anemia virus (EIAV), and feline (FIV) and bovine immunodeficiency viruses (BIV), specifically focusing on the antiviral role of the major restriction factors described thus far.
Collapse
MESH Headings
- Animals
- Cats
- Cattle
- Dendritic Cells/immunology
- Dendritic Cells/virology
- Gene Expression Regulation/immunology
- Goats
- Horses
- Immunity, Innate
- Immunodeficiency Virus, Bovine/immunology
- Immunodeficiency Virus, Bovine/pathogenicity
- Immunodeficiency Virus, Feline/immunology
- Immunodeficiency Virus, Feline/pathogenicity
- Infectious Anemia Virus, Equine/immunology
- Infectious Anemia Virus, Equine/pathogenicity
- Interferon Regulatory Factors/genetics
- Interferon Regulatory Factors/immunology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/virology
- Lentivirus Infections/genetics
- Lentivirus Infections/immunology
- Lentivirus Infections/virology
- Macrophages/immunology
- Macrophages/virology
- Pathogen-Associated Molecular Pattern Molecules/immunology
- Receptors, Pattern Recognition/genetics
- Receptors, Pattern Recognition/immunology
- Sheep
- T-Lymphocytes/immunology
- T-Lymphocytes/virology
Collapse
Affiliation(s)
- Lorena de Pablo-Maiso
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Ana Doménech
- Dpto. Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain.
| | - Irache Echeverría
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Carmen Gómez-Arrebola
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Damián de Andrés
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| | - Sergio Rosati
- Malattie Infettive degli Animali Domestici, Dipartimento di Scienze Veterinarie, Università degli Studi di Torino, Torino 10095, Italy.
| | - Esperanza Gómez-Lucia
- Dpto. Sanidad Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid 28040, Spain.
| | - Ramsés Reina
- Instituto de Agrobiotecnología (IdAB), UPNA-CSIC-Gobierno de Navarra, Navarra 31192, Spain.
| |
Collapse
|
9
|
Perrone R, Lavezzo E, Palù G, Richter SN. Conserved presence of G-quadruplex forming sequences in the Long Terminal Repeat Promoter of Lentiviruses. Sci Rep 2017; 7:2018. [PMID: 28515481 DOI: 10.1038/s41598-017-02291-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 04/03/2017] [Indexed: 12/25/2022] Open
Abstract
G-quadruplexes (G4s) are secondary structures of nucleic acids that epigenetically regulate cellular processes. In the human immunodeficiency lentivirus 1 (HIV-1), dynamic G4s are located in the unique viral LTR promoter. Folding of HIV-1 LTR G4s inhibits viral transcription; stabilization by G4 ligands intensifies this effect. Cellular proteins modulate viral transcription by inducing/unfolding LTR G4s. We here expanded our investigation on the presence of LTR G4s to all lentiviruses. G4s in the 5′-LTR U3 region were completely conserved in primate lentiviruses. A G4 was also present in a cattle-infecting lentivirus. All other non-primate lentiviruses displayed hints of less stable G4s. In primate lentiviruses, the possibility to fold into G4s was highly conserved among strains. LTR G4 sequences were very similar among phylogenetically related primate viruses, while they increasingly differed in viruses that diverged early from a common ancestor. A strong correlation between primate lentivirus LTR G4s and Sp1/NFκB binding sites was found. All LTR G4s folded: their complexity was assessed by polymerase stop assay. Our data support a role of the lentiviruses 5′-LTR G4 region as control centre of viral transcription, where folding/unfolding of G4s and multiple recruitment of factors based on both sequence and structure may take place.
Collapse
|