scholarly journals Identification of diverse groups of endogenous gammaretroviruses in mega- and microbats

2012 ◽  
Vol 93 (9) ◽  
pp. 2037-2045 ◽  
Author(s):  
Jie Cui ◽  
Gilda Tachedjian ◽  
Mary Tachedjian ◽  
Edward C. Holmes ◽  
Shuyi Zhang ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Leukemia Virus ◽  
Large Deletion ◽  
Endogenous Retroviruses ◽  
Myotis Lucifugus ◽  
Phylogenetic Study ◽  
Endogenous Virus ◽  
Pteropus Vampyrus ◽  
Gibbon Ape Leukemia Virus ◽  
Diverse Groups

A previous phylogenetic study suggested that mammalian gammaretroviruses may have originated in bats. Here we report the discovery of RNA transcripts from two putative endogenous gammaretroviruses in frugivorous (Rousettus leschenaultii retrovirus, RlRV) and insectivorous (Megaderma lyra retrovirus, MlRV) bat species. Both genomes possess a large deletion in pol, indicating that they are defective retroviruses. Phylogenetic analysis places RlRV and MlRV within the diversity of mammalian gammaretroviruses, with the former falling closer to porcine endogenous retroviruses and the latter to Mus dunni endogenous virus, koala retrovirus and gibbon ape leukemia virus. Additional genomic mining suggests that both microbat (Myotis lucifugus) and megabat (Pteropus vampyrus) genomes harbour many copies of endogenous retroviral forms related to RlRV and MlRV. Furthermore, phylogenetic analysis reveals the presence of three genetically diverse groups of endogenous gammaretroviruses in bat genomes, with M. lucifugus possessing members of all three groups. Taken together, this study indicates that bats harbour distinct gammaretroviruses and may have played an important role as reservoir hosts during the diversification of mammalian gammaretroviruses.

scholarly journals The Nucleotide Sequence of Koala (Phascolarctos cinereus) Retrovirus: a Novel Type C Endogenous Virus Related to Gibbon Ape Leukemia Virus

2000 ◽  
Vol 74 (9) ◽  
pp. 4264-4272 ◽  
Author(s):  
Jon J. Hanger ◽  
Lindell D. Bromham ◽  
Jeff J. McKee ◽  
Tracy M. O'Brien ◽  
Wayne F. Robinson
Keyword(s):  
Reverse Transcriptase ◽  
Genomic Dna ◽  
Leukemia Virus ◽  
Endogenous Retrovirus ◽  
Reverse Transcriptase Activity ◽  
Endogenous Virus ◽  
Peripheral Blood Mononuclear ◽  
Phascolarctos Cinereus ◽  
Clinically Normal ◽  
Gibbon Ape Leukemia Virus

ABSTRACT A novel retrovirus, morphologically consistent with mammalian C-type retroviruses, was detected by electron microscopy in mitogen-stimulated peripheral blood mononuclear cell cultures from 163 koalas and in lymphoma tissue from 3 koalas. PCR amplified provirus from the blood and tissues of 17 wild and captive koalas, and reverse transcriptase-PCR demonstrated viral mRNA, viral genomic RNA, and reverse transcriptase activity in koala serum and cell culture supernatants. Comparison of viral sequences derived from genomic DNA and mRNA showed identity indicative of a single retroviral species—here designated koala retrovirus (KoRV). Southern blot analysis of koala tissue genomic DNA using labelled KoRV probes demonstrated banding consistent with an endogenous retrovirus. Complete and apparently truncated proviruses were detected in DNA of both clinically normal koalas and those with hematopoietic disease. KoRV-related viruses were not detected in other marsupials, and phylogenetic analysis showed that KoRV paradoxically clusters with gibbon ape leukemia virus (GALV). The strong similarity between GALV and KoRV suggests that these viruses are closely related and that recent cross-host transmission has occurred. The complete proviral DNA sequence of KoRV is reported.

scholarly journals Porcine Endogenous Retroviruses Infect Cells Lacking Cognate Receptors by an Alternative Pathway: Implications for Retrovirus Evolution and Xenotransplantation

2004 ◽  
Vol 78 (16) ◽  
pp. 8868-8877 ◽  
Author(s):  
Dimitri Lavillette ◽  
David Kabat
Keyword(s):  
Host Range ◽  
Receptor Binding ◽  
Envelope Glycoprotein ◽  
Alternative Pathway ◽  
Leukemia Virus ◽  
Endogenous Retroviruses ◽  
Wild Type ◽  
Porcine Endogenous Retroviruses ◽  
Gibbon Ape Leukemia Virus ◽  
Porcine Tissues

ABSTRACT A PHQ motif near the amino termini of gammaretroviral envelope glycoprotein surface (SU) subunits is important for infectivity but not for incorporation into virions or binding to cognate receptors. The H residue of this motif is most critical, with all substitutions we tested being inactive. Interestingly, porcine endogenous retroviruses (PERVs) of all three host-range groups, A, B, and C, lack full PHQ motifs, but most members have an H residue at position 10. H10A PERV mutants are noninfectious but were efficiently transactivated by adding to the assays a PHQ-containing SU or receptor-binding subdomain (RBD) derived from a gibbon ape leukemia virus (GALV). A requirement of this transactivation was a functional GALV receptor on the cells. In contrast to this heterologous transactivation, PERV RBDs and SUs were inactive in all tested cells, including porcine ST-IOWA cells. Surprisingly, transactivation by GALV RBD enabled wild-type or H10A mutant PERVs of all three host-range groups to efficiently infect cells from humans and rodents that lack functional PERV receptors and it substantially enhanced infectivities of wild-type PERVs, even for cells with PERV receptors. Thus, PERVs can suboptimally infect cells that contain cognate receptors or they can employ a transactivation pathway to more efficiently infect all cells. This ability to infect cells lacking cognate receptors was previously demonstrated only for nontransmissible variant gammaretroviruses with recombinant and mutant envelope glycoproteins. We conclude that some endogenously inherited mammalian retroviruses also have a receptor-independent means for overcoming host-range and interference barriers, implying a need for caution in xenotransplantation, especially of porcine tissues.

scholarly journals Sequence Analysis of Mus dunni Endogenous Virus Reveals a Hybrid VL30/Gibbon Ape Leukemia Virus-Like Structure and a Distinct Envelope

1998 ◽  
Vol 72 (9) ◽  
pp. 7459-7466 ◽  
Author(s):  
Greg Wolgamot ◽  
Lynn Bonham ◽  
A. Dusty Miller
Keyword(s):  
Leukemia Virus ◽  
Open Reading Frames ◽  
Cell Entry ◽  
Endogenous Virus ◽  
Entire Genome ◽  
Naturally Occurring ◽  
Gibbon Ape Leukemia Virus ◽  
Apparent Similarity ◽  
Packaging Sequence ◽  
Reading Frames

ABSTRACT Mus dunni endogenous virus (MDEV) can be activated fromM. dunni cells by exposing the cells to hydrocortisone or 5-iodo-2′-deoxyuridine. Interference analysis has revealed that MDEV uses a receptor for cell entry that is different from those used by other murine retroviruses. The entire genome has now been sequenced, revealing a long terminal repeat (LTR)-gag-pol-env-LTR structure typical of simple retroviruses of the murine leukemia virus genus, with no additional open reading frames between env and the 3′ LTR. The LTRs and other noncoding regions of MDEV are most closely related to those of VL30 elements, while the majority of the coding sequences are most closely related to those of gibbon ape leukemia virus. MDEV represents the first example of a naturally occurring, replication-competent virus with sequences closely related to VL30 elements. The U3 region of MDEV contains six nearly perfect 80-bp repeats and the beginning of a seventh, and the region expected to contain the packaging sequence contains approximately four imperfect 33-bp repeats. The receptor specificity domains of the envelope are unique among retroviruses and show no apparent similarity to regions of known proteins.

Aberrant Type C Virus Production in a Cell Line Derived from Balb/3T3

1972 ◽  
Vol 30 ◽  
pp. 286-287
Author(s):  
N. Savage ◽  
A. Hackett
Keyword(s):  
Electron Microscopy ◽  
Cell Line ◽  
Leukemia Virus ◽  
Morphological Characteristics ◽  
Virus Production ◽  
Oncogenic Viruses ◽  
Endogenous Virus ◽  
Virus Particles ◽  
Moloney Leukemia Virus ◽  
A Cell

A cell line, UC1-B, which was derived from Balb/3T3 cells, maintains the same morphological characteristics of the non-transformed parental culture, and shows no evidence of spontaneous virus production. Survey by electron microscopy shows that the cell line consists of spindle-shaped cells with no unusual features and no endogenous virus particles.UC1-B cells respond to Moloney leukemia virus (MLV) infection by a change in morphology and growth pattern which is typical of cells transformed by sarcoma virus. Electron microscopy shows that the cells are now variable in shape (rounded, rhomboid, and spindle), and each cell type has some microvilli. Virtually all (90%) of the cells show virus particles developing at the cell surface and within the cytoplasm. Maturing viruses, typical of the oncogenic viruses, are found along with atypical tubular forms in the same cell.

scholarly journals Diversity of pathogenic Pseudomonas isolated from citrus in Tunisia

AMB Express ◽  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Maroua Oueslati ◽  
Magdalena Mulet ◽  
Mohamed Zouaoui ◽  
Charlotte Chandeysson ◽  
Jorge Lalucat ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Pseudomonas Syringae ◽  
Ice Nucleation ◽  
Phylogenetic Study ◽  
Future Studies ◽  
Citrus Orchards ◽  
First Time ◽  
New Cultivars

Abstract The damages observed in Tunisian citrus orchards have prompted studies on the Pseudomonas spp. responsible for blast and black pit. Prospective orchards between 2015 and 2017 showed that the diseases rapidly spread geographically and to new cultivars. A screening of Pseudomonas spp. isolated from symptomatic trees revealed their wide diversity according to phylogenetic analysis of their housekeeping rpoD and cts genes. The majority of strains were affiliated to Pseudomonas syringae pv. syringae (Phylogroup PG02b), previously described in Tunisia. However, they exhibited various BOX-PCR fingerprints and were not clonal. This work demonstrated, for the first time in Tunisia, the involvement of Pseudomonas cerasi (PG02a) and Pseudomonas congelans (PG02c). The latter did not show significant pathogenicity on citrus, but was pathogenic on cantaloupe and active for ice nucleation that could play a role in the disease. A comparative phylogenetic study of citrus pathogens from Iran, Montenegro and Tunisia revealed that P. syringae (PG02b) strains are closely related but again not clonal. Interestingly P. cerasi (PG02a) was isolated in two countries and seems to outspread. However, its role in the diseases is not fully understood and it should be monitored in future studies. The diversity of pathogenic Pseudomonas spp. and the extension of the diseases highlight that they have become complex and synergistic. It opens questions about which factors favor diseases and how to fight against them efficiently and with sustainable means.

A Defined Window for Efficient Gene Marking of Severe Combined Immunodeficient-Repopulating Cells Using a Gibbon Ape Leukemia Virus-Pseudotyped Retroviral Vector

2000 ◽  
Vol 11 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Christophe Demaison ◽  
Gaby Brouns ◽  
Michael P. Blundell ◽  
Jacki P. Goldman ◽  
Roland J. Levinsky ◽  
...  
Keyword(s):  
Leukemia Virus ◽  
Retroviral Vector ◽  
Efficient Gene ◽  
Gibbon Ape Leukemia Virus

Binding of a cellular protein to the gibbon ape leukemia virus enhancer

1987 ◽  
Vol 7 (8) ◽  
pp. 2735-2744
Author(s):  
J P Quinn ◽  
N Holbrook ◽  
D Levens
Keyword(s):  
Long Terminal Repeat ◽  
Specific Binding ◽  
Leukemia Virus ◽  
Cellular Protein ◽  
Terminal Repeat ◽  
Enhancer Activity ◽  
Repeated Element ◽  
Gibbon Ape Leukemia Virus

The gibbon ape leukemia virus (GALV) contains enhancer activity within its long terminal repeat. In the GALV Seato strain this activity resides in a 48-base-pair (bp) repeated element. We demonstrate the existence of a cellular protein which binds in this region of the Seato strain. A sensitive method for enriching protein-DNA complexes from crude extracts coupled with exonuclease and DNase footprint analysis revealed the specific binding of this protein to a 21-bp region within each repeated element. A 22-bp oligonucleotide fragment defined solely by the 21-bp footprint binds a protein in vitro and displays enhancer activity in vivo, suggesting that this protein is a major determinant of GALV enhancer activity. The protein is present in three cell lines which are positive for enhancer activity and is not detected in Jurkat cells, which are negative for enhancer activity. Only GALV long-terminal-repeat variants which support high levels of enhancer activity in vivo compete with this protein for specific binding in vitro, suggesting a potential role for the protein in determining enhancer activity. This protein binding is not inhibited by competition with heterologous retroviral enhancers, demonstrating that it is not a ubiquitous retroviral enhancer binding protein.

scholarly journals Improved transfer of the leukocyte integrin CD18 subunit into hematopoietic cell lines by using retroviral vectors having a gibbon ape leukemia virus envelope

Blood ◽  
1995 ◽  
Vol 86 (6) ◽  
pp. 2379-2387 ◽  
Author(s):  
TR Jr Bauer ◽  
AD Miller ◽  
DD Hickstein
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
Leukemia Virus ◽  
K562 Cells ◽  
Retroviral Vectors ◽  
Packaging Cell Line ◽  
Virus Receptor ◽  
Packaging Cell ◽  
Trna Primer ◽  
Gibbon Ape Leukemia Virus

Leukocyte adherence deficiency (LAD) is an inherited immunodeficiency disease caused by defects in the CD18 leukocyte integrin subunit. Transduction of CD18 into hematopoietic cells from children with LAD represents a potential therapy for this disorder. In an attempt to maximize transfer and expression of CD18, we evaluated retroviral vectors with and without the neomycin selectable marker, with a modified tRNA primer binding site designed to prevent inhibition of gene expression, and with two different viral envelope proteins produced by using the amphotropic retrovirus packaging cell line PA317 or the gibbon ape leukemia virus packaging cell line PG13. The vectors were tested using transducing K562/CD11b cells and LAD Epstein-Barr virus (EBV) B cells and measuring levels of cell-surface CD11/CD18 expression by fluorescence-activated cell sorter analysis. The best results were obtained with vectors made using PG13 packaging cells, for which about 25% of the K562 cells exposed once to the vectors expressed surface CD11b/CD18 and about 25% of the LAD EBV B cells exposed three times over a 3-day period to the vectors expressed surface CD11a/CD18. In contrast, transduction of cells under similar conditions with retroviral vectors produced using PA317 producer cells yielded less than 2% of the K562 cells and less than 4% of the LAD EBV B cells expressing the CD11/CD18 heterodimer on the cell surface. The presence or absence of the neomycin resistance gene or the modified tRNA primer had no effect on CD18 gene transfer rate or expression level. The increase in transduction with PG13 vectors correlated with Northern blotting and reverse transcription-polymerase chain reaction studies that indicated that both K562 cells and the LAD EBV B cells express transcripts for the gibbon ape leukemia virus receptor at higher levels than for the amphotropic virus receptor. These findings indicate that the transduction efficiency of retroviral packaging cell lines correlates with receptor gene expression in the target cells and that vectors made using PG13 cells may be efficacious for gene therapy for LAD and other diseases in which gene transfer to hematopoietic cells is required.

Sign in / Sign up

Export Citation Format

Share Document