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Journal of Virology Aug 1981We have analyzed the state, arrangement, and expression of polyoma viral DNA sequences in a number of in vitro-transformed Fischer rat cells before and after growth in...
We have analyzed the state, arrangement, and expression of polyoma viral DNA sequences in a number of in vitro-transformed Fischer rat cells before and after growth in vivo as tumour cells. When the in vitro lines used to induce the tumors contained only a single insert of viral sequences and did not produce either a full-size 100,000-dalton (100K) large T-antigen or free viral genomes, no differences in the above-mentioned properties were observed. By contrast, in vitro cell lines containing multiple inserts of viral sequences, a functional 100K large T-antigen, and free viral genome induced tumor cells which displayed a reduced number of inserts of viral sequences and which did not produce either a functional 100K large T-antigen or free viral genomes. All of the in vitro lines and their tumor cell derivatives expressed the polyoma virus 55K middle and 22K small T-antigen species. Possible mechanisms for the selection in vivo against cells containing a functional 100K large T-antigen and consequently free viral genomes are discussed.
Topics: Animals; Antigens, Neoplasm; Antigens, Viral; Antigens, Viral, Tumor; Base Sequence; Cell Line; Cell Transformation, Viral; DNA, Viral; Genes, Viral; Male; Neoplasms, Experimental; Polyomavirus; Rats
PubMed: 6268833
DOI: 10.1128/JVI.39.2.422-431.1981 -
Microbiological Reviews Sep 1979
Review
Topics: Animals; Cell Nucleus; Cells, Cultured; Chromatin; DNA Replication; DNA, Viral; Histones; Nucleosomes; Polyomavirus; Simian virus 40
PubMed: 232241
DOI: 10.1128/mr.43.3.297-319.1979 -
Journal of Virology Jan 1975Nucleoprotein complexes containing viral DNA and cellular histones were extracted from nuclei of permissive cells infected with polyoma virus or simian virus 40 (SV40)... (Comparative Study)
Comparative Study
Nucleoprotein complexes containing viral DNA and cellular histones were extracted from nuclei of permissive cells infected with polyoma virus or simian virus 40 (SV40) and examined by electron microscopy. Polyoma and SV40 nucleoprotein complexes are almost identical. They appear as relaxed circular molecules consisting of 20 to 21 globular particles interconnected by thin filaments. Their contour length in 0.02 M salt is 2.7 times shorter than that of viral DNA form I obtained after dissociation of the proteins in 1 M NaCl. The nucleosomes have an average diameter of 12.5 nm. Each nucleosome contains 175 to 205 DNA base pairs condensed fivefold in length. The nucleosomes are regularly spaced on the circular molecule. The internucleosomal filaments are made of naked DNA, and each filament contains about 55 base pairs. The partial sensitivity of the nucleoprotein complex to cleavage by EcoR1 endonuclease suggests that the nucleosomes are not formed at specific sites on the viral genome. Faster sedimenting nucleoprotein complexes containing replicative intermediates were studied. Isopycnic centrifugation in metrizamide gradients in the absence of aldehyde fixation showed that these molecules conserved the same DNA-to-protein ratio as the form I DNA-containing complexes.
Topics: Cell Nucleus; Cells, Cultured; Centrifugation, Density Gradient; Chromatin; DNA Restriction Enzymes; DNA, Viral; Histones; Metrizamide; Microscopy, Electron; Nucleoproteins; Polyomavirus; Simian virus 40; Virus Replication
PubMed: 173884
DOI: 10.1128/JVI.17.1.204-211.1976 -
The American Journal of Pathology Apr 1999Polyoma virus infection causes acute interstitial nephritis and ureteral stenosis in humans but has rarely been noted in other species. In the present study, a hitherto...
Cynomolgus polyoma virus infection: a new member of the polyoma virus family causes interstitial nephritis, ureteritis, and enteritis in immunosuppressed cynomolgus monkeys.
Polyoma virus infection causes acute interstitial nephritis and ureteral stenosis in humans but has rarely been noted in other species. In the present study, a hitherto unknown polyoma virus was detected in 12 of 57 cynomolgus monkeys after 3 to 11 weeks of immunosuppression given to promote acceptance of renal allografts or xenografts. This virus, termed cynomolgus polyoma virus (CPV), is antigenically and genomically related to simian virus 40 (SV40). The tubular epithelial nuclei of the collecting ducts in the medulla and cortex reacted with an antibody for the SV40 large T antigen and by electron microscopy contained densely packed paracrystalline arrays of 30- to 32-nm diameter viral particles. A polymerase chain reaction analysis of DNA extracted from affected kidneys detected polyoma virus sequences using primers for a highly conserved region of the large T antigen of polyoma virus. Sequence analysis showed 7 base substitutions and 3 to 5 deletions in the 129-nucleotide segment of amplified products, compared with the corresponding portion of SV40, yielding 84% homology at the amino acid level. CPV caused interstitial nephritis in six renal allografts, a xenograft kidney, and six native kidneys. Infected animals showed renal dysfunction and had tubulointerstitial nephritis with nuclear inclusions, apoptosis, and progressive destruction of collecting ducts. CPV was detected in the urothelium of graft ureters, associated with ureteritis and renal infection. Viral infection was demonstrable in smooth muscle cells of the ureteric wall, which showed apoptosis. One animal had diarrhea and polyoma virus infection in the smooth muscle cells of the muscularis propria of the intestine. Spontaneous resolution occurred in one case; no animal had virus detected in tissues more than 3 months after transplantation. Thus, immunosuppression predisposes cynomolgus monkeys to a polyoma virus infection with clinical consequences quite similar to BK virus infection in humans, including renal dysfunction. We also suggest that this may be the pathogenetic basis for the significant incidence of late onset, isolated ureteral stenosis observed in these recipients.
Topics: Animals; Antigens, Viral, Tumor; DNA, Viral; Disease Models, Animal; Enteritis; Immunocompromised Host; Intestines; Kidney; Kidney Transplantation; Macaca fascicularis; Microscopy, Electron; Molecular Sequence Data; Nephritis, Interstitial; Papillomavirus Infections; Polymerase Chain Reaction; Polyomavirus; Tumor Virus Infections; Ureteral Diseases
PubMed: 10233865
DOI: 10.1016/S0002-9440(10)65379-5 -
Indian Journal of Medical Microbiology Feb 2015To optimise a polymerase chain reaction (PCR) based DNA sequencing technique for genotyping polyoma virus in clinical specimens obtained from renal transplant patients.
PURPOSE
To optimise a polymerase chain reaction (PCR) based DNA sequencing technique for genotyping polyoma virus in clinical specimens obtained from renal transplant patients.
MATERIALS AND METHODS
A hundred and thirty (106 peripheral blood and 24 urine) clinical specimens collected from renal transplant patients were included in the study for detecting the presence of DNA of BK virus (BKV), JC virus (JCV) by PCR targeting the viral protein 1 (VP1) gene. PCR based DNA sequencing was performed to determine the genotypes of polyoma virus and subjected to bioinformatics analysis to determine the amino acid sequences and screen for mutations in the VP1 gene.
RESULTS
Polyoma virus was detected in 23 (17.69%) specimens of which 19 (82.60%) were positive for BK virus, 3 (13.04%) for JC virus and 1 for both BK and JC virus. PCR based DNA sequencing detected BK virus genotype I in 12 (50%), genotype IV in 8 (33.3%) and JC virus in 4 (16.6%) clinical specimens. BKV genotype I was the predominant genotype (64.2% in peripheral blood and 33.33% in urine) prevalent in south India. Six novel mutations were found--at position 29, 30 to 47 of BKV genotype I; at position 11 and 15 of BKV genotype IV and at position 2 and 30 of JCV.
CONCLUSION
BKV genotype I is the prominent genotype in India and novel mutations detected in the VP1 gene of BKV and JCV are being reported for the first time in literature.
Topics: Amino Acid Sequence; BK Virus; Capsid Proteins; Genotype; Genotyping Techniques; Humans; India; JC Virus; Kidney Transplantation; Molecular Sequence Data; Polymerase Chain Reaction; Polyomavirus; Polyomavirus Infections; Real-Time Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA
PubMed: 25657154
DOI: 10.4103/0255-0857.150878 -
Nucleic Acids Research Oct 1979The DNA sequence of the early coding region of polyoma virus is presented. It consists of 2739 nucleotides. The sequence predicts that more than one reading frame can be... (Comparative Study)
Comparative Study
The DNA sequence of the early coding region of polyoma virus is presented. It consists of 2739 nucleotides. The sequence predicts that more than one reading frame can be used to code for the three known polyoma virus early proteins (designated small, middle and large T-antigens). From the DNA sequence, the 'splicing' signals used in the processing of viral RNA to functional messenger RNAs can be predicted, as well as the sizes and sequences of the three proteins. Other unusual aspects of the DNA sequence are noted. Comparisons are made between the DNA sequences and the predicted amino acid sequences of the respective large T-antigens of polyoma virus and the related virus Simian Virus (SV) 40.
Topics: Antigens, Viral; Base Sequence; DNA, Viral; Polyomavirus; RNA, Messenger; Simian virus 40
PubMed: 228249
DOI: 10.1093/nar/7.4.839 -
Virology Feb 2009Middle T antigen (MT) is the principal oncogene of murine polyomavirus. Its study has led to the discovery of the roles of tyrosine kinase and phosphoinositide 3-kinase... (Review)
Review
Middle T antigen (MT) is the principal oncogene of murine polyomavirus. Its study has led to the discovery of the roles of tyrosine kinase and phosphoinositide 3-kinase (PI3K) signaling in mammalian growth control and transformation. MT is necessary for viral transformation in tissue culture cells and tumorigenesis in animals. When expressed alone as a transgene, MT causes tumors in a wide variety of tissues. It has no known catalytic activity, but rather acts by assembling cellular signal transduction molecules. Protein phosphatase 2A, protein tyrosine kinases of the src family, PI3K, phospholipase Cgamma1 as well as the Shc/Grb2 adaptors are all assembled on MT. Their activation sets off a series of signaling cascades. Analyses of virus mutants as well as transgenic animals have demonstrated that the effects of a given signal depend not only tissue type, but on the genetic background of the host animal. There remain many opportunities as we seek a full molecular understanding of MT and apply some of its lessons to human cancer.
Topics: Animals; Antigens, Polyomavirus Transforming; Cell Transformation, Viral; Genes, src; Phosphatidylinositol 3-Kinases; Phosphorylation; Polyomavirus; Protein Binding; Protein Phosphatase 2; Protein-Tyrosine Kinases; Signal Transduction
PubMed: 19022468
DOI: 10.1016/j.virol.2008.09.042 -
Microbiology and Molecular Biology... Jun 2001"It has been commented by someone that 'polyoma' is an adjective composed of a prefix and suffix, with no root between--a meatless linguistic sandwich" (C. J. Dawe). The... (Review)
Review
"It has been commented by someone that 'polyoma' is an adjective composed of a prefix and suffix, with no root between--a meatless linguistic sandwich" (C. J. Dawe). The very name "polyomavirus" is a vague mantel: a name given before our understanding of these viral agents was clear but implying a clear tumor life-style, as noted by the late C. J. Dawe. However, polyomavirus are not by nature tumor-inducing agents. Since it is the purpose of this review to consider the natural function of middle T antigen (MT), encoded by one of the seemingly crucial transforming genes of polyomavirus, we will reconsider and redefine the virus and its MT gene in the context of its natural biology and function. This review was motivated by our recent in vivo analysis of MT function. Using intranasal inoculation of adult SCID mice, we have shown that polyomavirus can replicate with an MT lacking all functions associated with transformation to similar levels to wild-type virus. These observations, along with an almost indistinguishable replication of all MT mutants with respect to wild-type viruses in adult competent mice, illustrate that MT can have a play subtle role in acute replication and persistence. The most notable effect of MT mutants was in infections of newborns, indicating that polyomavirus may be highly adapted to replication in newborn lungs. It is from this context that our current understanding of this well-studied virus and gene is presented.
Topics: Animals; Antigens, Polyomavirus Transforming; Apoptosis; Cell Differentiation; Cell Transformation, Viral; Eukaryotic Cells; Mice; Mice, Knockout; Polyomavirus; Signal Transduction; Transcription, Genetic; Virus Replication
PubMed: 11381103
DOI: 10.1128/MMBR.65.2.288-318.2001 -
The EMBO Journal Mar 1984We have recently proposed that the transforming protein of polyoma virus, middle-T antigen, forms a complex with pp60c-src. Here we provide additional evidence for the...
We have recently proposed that the transforming protein of polyoma virus, middle-T antigen, forms a complex with pp60c-src. Here we provide additional evidence for the existence of the complex using both monoclonal antibodies specific for middle-T and antibodies raised against synthetic peptides corresponding to sequences from both middle-T and pp60c-src. The complex was retained during partial purification of middle-T and was stable to incubation under various conditions. A survey of a number of mutants of middle-T antigen showed that there was a complete correlation between the ability of middle-T to accept phosphate in the in vitro kinase reaction and the presence of a middle-T: pp60c-src complex. This result is in accord with our hypothesis that middle-T itself is not a protein kinase but rather that pp60c-src phosphorylates middle-T. All mutant forms of middle-T antigen capable of transformation had associated pp60c-src. The middle-T of two non-transforming mutants (hr-t mutants) did not have associated pp60c-src, whereas other non-transforming middle-T species did associate with pp60c-src. We propose that the complex plays an essential role in transformation by polyoma virus, but that the existence of the complex per se may not be sufficient.
Topics: Antigens, Viral, Tumor; Cell Transformation, Viral; Cells, Cultured; Macromolecular Substances; Oncogene Protein pp60(v-src); Polyomavirus; Protein Kinases; Viral Proteins
PubMed: 6325177
DOI: 10.1002/j.1460-2075.1984.tb01852.x -
The Journal of Experimental Medicine May 1959Mouse polyoma virus was stored at 4 degrees and -60 degrees C. for 8 weeks without any loss in hemagglutination or infectivity titer; storage at 37 degrees for 8 weeks...
Mouse polyoma virus was stored at 4 degrees and -60 degrees C. for 8 weeks without any loss in hemagglutination or infectivity titer; storage at 37 degrees for 8 weeks reduced infectivity titer by approximately 2.5 log(10) units. Repeated freezing and thawing of infectious tissue culture fluid had no effect on virus titer. The stability of the virus to storage for 1 week at 4 degrees C. was unaffected by suspension of infected tissue culture fluid in saline, demineralized distilled water, or 5 per cent horse serum in Eagle's basal medium. Heating the virus for 30 minutes at 60 degrees C. had no effect on infectivity and hemagglutination titers. Heating at 65 degrees C. for 30 minutes produced a 3 log unit loss of infectivity and a 4-fold decline in HA titer, and heating at 70 degrees C. for 30 minutes usually produced complete inactivation of infectivity and HA. The virus was resistant to ultraviolet irradiation; ultraviolet irradiation for 2 hours caused a 4 log unit decrease in infectivity titer without affecting the HA titer. The virus was resistant to exposure to 2 per cent phenol and 50 per cent ethyl alcohol but was inactivated by 100 per cent ethyl alcohol, and ethyl alcohol-iodine mixtures. Lyophilization had no effect on the stability of the virus.
Topics: Animals; Mice; Polyomavirus; Viruses
PubMed: 13641568
DOI: 10.1084/jem.109.5.439