Publications

phosphorylation of the budgerigar fledgling disease virus major capsid protein vp1.	the structural proteins of the budgerigar fledgling disease virus, the first known nonmammalian polyomavirus, were analyzed by isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). the major capsid protein vp1 was found to be composed of at least five distinct species having isoelectric points ranging from ph 6.45 to 5.85. by analogy with the murine polyomavirus, these species apparently result from different modifications of an initial translation produc ...	1992	1318417
production and characterization of monoclonal antibodies to budgerigar fledgling disease virus major capsid protein vp.	eleven hybridoma cell lines producing monoclonal antibodies (mabs) against intact budgerigar fledgling disease (bfd) virions were produced and characterized. these antibodies were selected for their ability to react with bfd virions in an enzyme-linked immunosorbent assay. each of these antibodies was reactive in the immunofluorescent detection of bfd virus-infected cells. these antibodies immunoprecipitated intact virions and specifically recognized the major capsid protein, vp1, of the dissoci ...	1992	1417586
polymerase chain reaction assay for avian polyomavirus.	a polymerase chain reaction assay was developed for detection of budgerigar fledgling disease virus (bfdv). the assay used a single set of primers complementary to sequences located in the putative coding region for the bfdv vp1 gene. the observed amplification product had the expected size of 550 bp and was confirmed to derive from bfdv dna by its restriction digestion pattern. this assay was specific for bfdv and highly sensitive, being able to detect as few as 20 copies of the virus. by using ...	1991	1647403
nuclear localization of budgerigar fledgling disease virus capsid protein vp2 is conferred by residues 308-317.	the capsid protein vp2 of budgerigar fledgling disease virus (bfdv) contains two sequences (residues 309-315 and 334-340) which are homologous to the prototypic nuclear localization sequence (nls) of the simian virus 40 t-antigen. using recombinant potential nls-beta-galactosidase fusion proteins we identified amino acid residues 308-317 (vpkrkrklpt) to be the nls of bfdv capsid proteins vp2 and vp3. microfluorometry studies show that the bfdv-vp2 signal is considerably more efficient in nuclear ...	1991	1657638
myristoylation of budgerigar fledgling disease virus capsid protein vp2.	we present evidence that the structural protein vp2 of budgerigar fledgling disease virus, an avian polyomavirus, is specifically modified by covalent attachment of myristic acid. the fatty acid linkage is insensitive to hydroxylamine treatment and thus represents the amide type of fatty acylation of proteins.	1989	2535744
serological evaluation of some psittaciformes for budgerigar fledgling disease virus.	breeding psittaciform birds (psittacines) from three geographically separated aviaries experiencing fledgling mortality were monitored during 1983 and 1984 for specific serum antibody to budgerigar fledgling disease virus (bfdv) using a fluorescent-antibody virus-neutralization test. neither the time nor the extent of exposure to the virus was known. serological titers were positive in 45% of birds sampled from aviary 1, 25% from aviary 2, and 11% from aviary 3. several species of psittacine bir ...	1987	2823781
the genome of budgerigar fledgling disease virus, an avian polyomavirus.	budgerigar fledgling disease virus (bfdv) represents the first avian member of the polyomavirus family. in contrast to mammalian polyomaviruses bfdv exhibits unique biological properties, in particular it is able to cause an acute disease with distinct organ manifestations in affected birds. here we present the complete nucleotide sequence of the bfdv genome, consisting of 4980 bp. when compared to published nucleotide sequences of other polyomaviruses, the bfdv genome exposes a number of very s ...	1988	2838972
cloning and characterization of budgerigar fledgling disease virus, an avian polyomavirus.	the dna of a virus isolated from fledgling budgerigars, designated bfdv, was cloned and analyzed with regard to its relationship to the polyomavirus subgroup of the papovavirus family. under relaxed conditions, the dna of bfdv cross-hybridized with the dnas of members of the polyomavirus subgroup, such as the mouse polyomavirus, the monkey viruses simian virus 40, stump-tailed macaque virus, and lymphotropic papovavirus, and the human viruses jcv and bkv. under stringent conditions, however, no ...	1986	3010557
investigations of budgerigar fledgling disease virus.	the dna of a papovavirus associated with budgerigar fledgling disease was purified and cloned into plasmid pbr322. the genome was circular and approximately 5.1 kilobases long. physical mapping of the genome with restriction endonucleases revealed little similarity to simian virus 40 or polyomavirus dna. transformation trials using murine 3t3 cells were negative. attempts to characterize proteins were unsuccessful due to the apparent close association of the virus and host cell components.	1984	6093653
early and late pre-mrna processing of budgerigar fledgling disease virus 1: identification of viral rna 5' and 3' ends and internal splice junctions.	budgerigar fledgling disease virus 1 (bfdv-1) is the first avian polyomavirus to be identified, and it possesses uncommon structural and biological properties. here we present an analysis of the processed viral rnas in infected chicken embryo fibroblast cells. two early and 18 late bfdv-1 mrnas were defined according to their 5' ends and internal splice patterns. in the early region of the genome an incomplete splice reaction covering 195 nt is responsible for creating two mrnas that could encod ...	1995	7844527
host restriction in the productive cycle of avian polyomavirus budgerigar fledgling disease virus type 3 depends on a single amino acid change in the common region of structural proteins vp2/vp3.	the three avian polyomaviruses budgerigar fledgling disease virus types 1 to 3 (bfdv-1 to -3) contain genomes of identical size, 4981 bp. with differences of up to only 15 bp between the three genomes, these viruses show distinct tropism for cultured cells of various avian species: infection of chicken embryo (ce) cells with bfdv-1 and -2 results in virus propagation, whereas bfdv-3 is not replicated; all three viruses replicate, with different efficiencies, in infected muscovy duck cells. trans ...	1994	8077924
purification of recombinant budgerigar fledgling disease virus vp1 capsid protein and its ability for in vitro capsid assembly.	a recombinant system for the major capsid vp1 protein of budgerigar fledgling disease virus has been established. the vp1 gene was inserted into a truncated form of the pflag-1 vector and expressed in escherichia coli. the budgerigar fledgling disease virus vp1 protein was purified to near homogeneity by immunoaffinity chromatography. fractions containing highly purified vp1 were pooled and found to constitute 3.3% of the original e. coli-expressed vp1 protein. electron microscopy revealed that ...	1994	8151798
expression and dna binding of budgerigar fledgling disease virus large t antigen.	budgerigar fledgling disease virus (bfdv) represents the first non-mammalian member of the polyomavirus genus and possesses uncommon structural and biological properties. recombinant baculoviruses were constructed to express bfdv small t antigen, large t antigens, as well as a large t deletion mutant td and beta-galactosidase-td fusion proteins to high levels in infected insect cells. a recombinant virus containing a genomic copy of the bfdv early region was used for small t antigen expression, ...	1994	8207393
infection with the avian polyomavirus, bfdv, selectively affects myofibril structure in embryonic chick ventricle cardiomyocytes.	embryonic cardiomyocytes can both beat and divide. they assemble cardiac muscle-specific proteins into sarcomeric myofibrils and contract. in addition, they periodically synthesize dna, complete mitosis, disassemble sarcomeric myofibrils in the area of the mitotic spindle, assemble cytoplasmic isoform-specific proteins into a cleavage furrow contractile ring, undergo cytokinesis, and then reform sarcomeric myofibrils in daughter cells. little is known about how embryonic cardiomyocytes disassemb ...	1993	8228865
molecular and biological characteristics of avian polyomaviruses: isolates from different species of birds indicate that avian polyomaviruses form a distinct subgenus within the polyomavirus genus.	the isolation and characterization of two avian polyomaviruses, from chicken (bfdv-2) and a parrot (bfdv-3), is reported. both isolates are closely related to the non-mammalian polyomavirus budgerigar fledgling disease virus (bfdv) isolated from budgerigars (now called bfdv-1), and all three viral genomes are shown to have the same basic size of 4981 bp. a 151 bp insertion was, however, observed in the non-coding region of bfdv-2 which represented an exact duplication of the left half of the non ...	1993	8381462
characterization of a calcium binding domain in the vp1 protein of the avian polyomavirus, budgerigar fledgling disease virus.	calcium ions appear to play a major role in maintaining the structural integrity and assembly of papovavirus virions and are likely involved in the process of viral uncoating. recently it was reported that the purified recombinant vp1 protein of budgerigar fledgling disease virus (bfdv) was capable of assembling into capsid-like particles in the presence of calcium. it is now reported that the major capsid protein vp1 of bfdv binds calcium ions in an in vitro calcium binding assay. two deletions ...	1996	8879141
the effect of space flight on monoclonal antibody synthesis in a hybridoma mouse cell line.	the hybridoma cell line, 3g10g5, producing a monoclonal antibody to the major capsid protein vp1 from the avian polyomavirus budgerigar fledgling disease virus, was produced from a balb/c mouse. this cell line was used to test the effects of microgravity on cellular processes, specifically protein synthesis. a time course study utilizing incorporation of [35s]methionine into newly synthesized monoclonal antibody was performed on sts-77. after 5.5 days, it was observed that cell counts for the sa ...	1997	9024803
avian polymavirus in wild birds: genome analysis of isolates from falconiformes and psittaciformes.	avian polyomavirus (apv) infections have been reported to cause fatal disease in a wide range of psittacine species. here we demonstrate apv infections in buzzards (buteo buteo) and in a falcon (falco tinnunculus) found dead in germany, and in lovebirds (agapornis pullaria) with fatal disease, wild-caught in moçambique. apv infection in buzzards was determined by pcr amplification of parts of the viral genome followed by southern blot hybridisation. the genomes of the isolates obtained from the ...	1998	9739329
recombinant expression of late genes agno-2a and agno-2b of avian polyomavirus bfdv.	budgerigar fledgling disease virus (bfdv) genome contains two times two (two pairs) open reading frames (agnogenes) at the 5' end of the late coding region. recombinant influenza a viruses were constructed to express the second pair of bfdv agnoproteins, agno-2a and agno-2b, with a fusion of a histidine-tag at their carboxy-termini, respectively. specific proteins were detected in western blot analysis using anti histidine-tag monoclonal antibody. by indirect immunofluorescence experiments agno- ...	1999	10595409
agnoprotein-1a of avian polyomavirus budgerigar fledgling disease virus: identification of phosphorylation sites and functional importance in the virus life-cycle.	the avian polyomavirus budgerigar fledgling disease virus (bfdv) encodes an unusual set of four agnoproteins in its late upstream region. of the two pairs of these proteins, which overlap each other in two different reading frames, the p(l1)-promoted agnoprotein-1a (agno-1a) is the dominant species and is able to support virus propagation in the absence of the other three polypeptides. viral bfdv agno-1a, and also agno-1a expressed via an influenza virus vector, consists of a complex series of e ...	2000	10644834
evidence for translation of vp3 of avian polyomavirus bfdv by leaky ribosomal scanning.	due to several incomplete splicing reactions, budgerigar fledgling disease virus (bfdv) late mature mrnas are either bicistronic or polycistronic with an agnogene located upstream of viral protein (vp) genes. while the bicistronic mrnas code for the vast majority of vp1, the polycistronic mrnas contain the coding sequences of vp2, vp3, and vp1 (as the most distal cistron relative to vp2 and vp3). in this work, the translation initiation mechanism of vp3 was investigated in chicken embryo fibrobl ...	2000	10752562
development of a blocking enzyme-linked immunosorbent assay for the detection of avian polyomavirus-specific antibodies.	avian polyomavirus, described originally as budgerigar fledgling disease virus, has been associated with devastating contagious disease outbreaks in budgerigar aviaries. at present, this virus affects a wide range of psittacine and non-psittacine birds worldwide, and the serum neutralisation test is used for the serodiagnosis of avian polyomavirus infections. a blocking enzyme-linked immunosorbent assay was developed for the screening of large numbers of sera collected from various avian species ...	2000	10996638
generation of recombinant virus-like particles of human and non-human polyomaviruses in yeast saccharomyces cerevisiae.	non-viral methods of gene transfer have been preferred in gene therapy approaches for several reasons, particularly for their safety, simplicity and convenience in introducing heterologous dna into cells. polyomavirus virus-like particles (vlps) represent a promising carrier for encapsidation of foreign nucleic acids for gene therapy. for the development of such gene delivery systems as well as for providing reagents for improving virus diagnostics, an efficient yeast expression system for the g ...	2002	12602348
a concurrent outbreak of psittacine beak and feather disease virus, and avian polyomavirus infection in budgerigars (melopsittacus undulatus).	a dual natural infection with psittacine beak and feather disease virus and budgerigar fledgling disease virus in a breeding aviary of budgerigars (melopsittacus undulatus) is described. one-hundred per cent of newly-hatched birds were affected and mortality was high (85%). most surviving birds had diarrhoea, feather alterations and 30% mortality after a 5- to 10-week period. necropsies of 1-week-old and 2-month-old birds demonstrated non-specific lesions, but histologically nuclear inclusions s ...	1998	18483964
a light and electron microscopic examination of budgerigar fledgling disease virus in tissue and in cell culture.	morphological changes induced by a newly described avian virus in budgerigar (melopsittacus undulatus) tissues were examined with light and electron microscopes. infected cells viewed with the light microscope were found to have enlarged nuclei containing marginated chromatin. cytoplasmic contents were frequently clear in appearance. tissues affected included skin, feather, follicle, kidney, uropygial gland, crop, lung, liver, heart, bone marrow, spleen and brain. serum from infected birds conta ...	1982	18770169
avian polyomavirus expression patterns of bicistronic late mrnas.	avian polyomavirus (apv, previously called budgerigar fledgling disease virus, bfdv-1) differs from other polyoma viruses by a complex arrangement within its late genes: p(l1)-promoted agno-genes 1a and 1b overlap p(l2)-promoted agno-genes 2a and 2b in different reading frames, and are located upstream of standard late vp genes. as a minimal set, agno-gene 1a plus vp1, vp2, vp3 support effective viral propagation in cell culture, together with the origin-region and t-antigen section. all viral l ...	2009	19329136
establishment of rapid detection method and surveillance of budgerigar fledgling disease virus using a taqman real-time pcr.	budgerigar fledgling disease virus (bfdv) infection causes sudden death, abdominal distention, and feather abnormality in psittacine birds. in this study, we developed a taqman real-time pcr assay to detect bfdv by targeting a conserved region in vp1 gene. the detection limit of the assay was 30 dna gene copies, 1000 times more sensitive than conventional pcr. the coefficients of variation were less than 1.09% in either intra- or inter-assays, indicating high reproducibility. by using this metho ...	2019	30414896
development of a colorimetric loop-mediated isothermal amplification assay for rapid and specific detection of aves polyomavirus 1 from psittacine birds.	a colorimetric loop-mediated isothermal amplification (lamp) assay was developed for the rapid and specific detection of the t gene of aves polyomavirus 1 (apyv), a causative agent of budgerigar fledgling disease (bfd) in psittacine birds. the amplification can be completed in 40 min at 60 °c, and the results can be visually detected by the naked eye using hydroxyl naphthol blue as a colorimetric indicator. the assay specifically amplified apyv dna but not other viral and bacterial nucleic acids ...	2019	31271791
isolation and characterization of an aves polyomavirus 1 from diseased budgerigars in china.	aves polyomavirus 1 (apv) causes inflammatory disease in psittacine birds, especially in young budgerigar. in this study, an apv virus (sd18 strain) was isolated from a diseased psittacine birds breeding facility. the full genome (4981 bp) of sd18 was determined and analyzed. phylogenetic analysis of full genome sequences indicated all the apv strains form two groups. the sd18 strain showed close relationship with apv isolated from poland, however, the other chinese strains are located in group ...	2019	31585638
monitoring of free-ranging and captive psittacula populations in western europe for avian bornaviruses, circoviruses and polyomaviruses.	avian pathogens such as bornaviruses, circoviruses and polyomaviruses are widely distributed in captive collections of psittacine birds worldwide and can cause fatal diseases. in contrast, only little is known about their presence in free-ranging psittacines and their impact on these populations. rose-ringed parakeets (psittacula krameri) and alexandrine parakeets (psittacula eupatria) are non-native to europe, but have established stable populations in parts of western europe. from 2012-2017, w ...	2020	31617746
genomic evolution of avian polyomaviruses with a focus on budgerigar fledgling disease virus.	gammapolyomaviruses may cause serious inflammatory diseases in a broad range of avian hosts. in this study we investigated genomic evolution of and selection constraint acting on avian polyomaviruses (apyvs). our analyses suggested that goose haemorrhagic polyomavirus (ghpv) evolves more slowly (3.03 × 10-5 s/s/y mean evolutionary rate) than budgerigar fledgling disease virus (bfdv), finch polyomavirus (fpyv) and canary polyomavirus (capyv) (1.39 × 10-4 s/s/y, 2.63 × 10-4 s/s/y and 1.41 × 10-4 s ...	2021	33571686