| a simplified method of constructing infectious clones of begomovirus employing limited restriction enzyme digestion of products of rolling circle amplification. | most infectious clones of geminiviruses consist of (partial) tandem repeats of viral genomes in the vectors, which usually involve tedious, multi-step assemblies of genomic fragments in the construction process. a simplified procedure was devised to circumvent these problems, which employs limited restriction digestion of multimeric viral genomes produced by rolling circle amplification (rca), followed by direct cloning into appropriate vectors. the efficiency of the procedure, and infectivity o ... | 2008 | 18031835 |
| replication promiscuity of dna-beta satellites associated with monopartite begomoviruses; deletion mutagenesis of the ageratum yellow vein virus dna-beta satellite localizes sequences involved in replication. | pseudorecombination studies in nicotiana benthamiana demonstrate that ageratum yellow vein virus (ayvv) and eupatorium yellow vein virus (epyvv) can functionally interact with dna-beta satellites associated with ayvv, epyvv, cotton leaf curl multan virus (clcumv) and honeysuckle yellow vein virus (hyvv). in contrast, clcumv shows some specificity in its ability to interact with distinct satellites and hyvv is able to interact only with its own satellite. using an n. benthamiana leaf disk assay, ... | 2008 | 19008407 |
| unit-length, single-stranded circular dnas of both polarity of begomoviruses are generated in escherichia coli harboring phage m13-cloned begomovirus genome with single copy of replication origin. | replication of genomic dnas of plant-pathogenic begomoviruses has been demonstrated in prokaryotes, which supported the possibility of analyzing dna replication process of begomoviruses in bacteria. however, previous studies indicated that the replication of begomovirus dnas in prokaryotes requires tandem constructs of viral genomes with at least two copies of the origin of replication (ori). in this study, phage m13 vector harboring the unit-length genome with only a single copy of ori of a mon ... | 2007 | 17204346 |
| molecular characterization of two distinct begomoviruses from papaya in china. | six papaya samples showing downward leaf curling were collected in guangdong and guangxi provinces, china. the result of tas-elisa showed they were all infected by geminiviruses. comparison of partial dna-a sequences reveals that these virus isolates can be classified into two groups. group i includes isolates g2, g4, g5, g28 and g29 from guangxi province, while isolate gd2 from guangdong province belongs to group ii. the complete dna-a sequence of g2 and gd2 were characterized. sequence compari ... | 2004 | 15550769 |
| the dna beta satellite component associated with ageratum yellow vein disease encodes an essential pathogenicity protein (betac1). | ageratum yellow vein disease (ayvd) is caused by the geminivirus ageratum yellow vein virus (ayvv) and an associated dna beta satellite. we have mapped a dna beta transcript to a highly conserved open reading frame (betac1 orf). the most abundant transcript 5'-terminus is located 8 bases upstream of the betac1 orf putative initiation codon while the transcript terminates at multiple sites downstream from the putative termination codon. disruption of betac1 protein expression by the introduction ... | 2004 | 15183051 |
| a geminivirus ayvv-derived shuttle vector for tobacco by2 cells. | we have developed a plant- escherichia coli pasv shuttle vector from the essential elements of the ageratum yellow vein virus (ayvv). the geminivirus vector contains the ayvv genome with the coat-protein deletion, the e. coli vector backbone of puc19, a unique cloning site and gene expression cassettes for plant selection and reporter gene activity. the replication of pasv vectors was compared in nicotiana benthamiana and n. tabacum by2 cells, and the latter were found to be suitable for long-te ... | 2004 | 15069580 |
| diversity of dna beta, a satellite molecule associated with some monopartite begomoviruses. | dna beta molecules are symptom-modulating, single-stranded dna satellites associated with monopartite begomoviruses (family geminiviridae). such molecules have thus far been shown to be associated with ageratum yellow vein virus from singapore and cotton leaf curl multan virus from pakistan. here, 26 additional dna beta molecules, associated with diverse plant species obtained from different geographical locations, were cloned and sequenced. these molecules were shown to be widespread in the old ... | 2003 | 12890625 |
| adaptation from whitefly to leafhopper transmission of an autonomously replicating nanovirus-like dna component associated with ageratum yellow vein disease. | ageratum yellow vein disease is caused by the whitefly-transmitted monopartite begomovirus ageratum yellow vein virus and a dna beta satellite component. naturally occurring symptomatic plants also contain an autonomously replicating nanovirus-like dna 1 component that relies on the begomovirus and dna beta for systemic spread and whitefly transmission but is not required for maintenance of the disease. here, we show that systemic movement of dna 1 occurs in nicotiana benthamiana when co-inocula ... | 2002 | 11907341 |
| characterisation of sri lankan cassava mosaic virus and indian cassava mosaic virus: evidence for acquisition of a dna b component by a monopartite begomovirus. | two bipartite begomoviruses, indian cassava mosaic virus (icmv) and sri lankan cassava mosaic virus (slcmv), have been isolated from mosaic-diseased cassava originating from central india and sri lanka, respectively. icmv was transmitted with low efficiency from cassava to nicotiana benthamiana by sap inoculation to give leaf curl symptoms. slcmv was much more virulent in this host, producing severe stunting, leaf curl, and chlorosis. these symptoms were reproduced when their cloned genomic comp ... | 2002 | 11853400 |
| molecular characterization of a distinct begomovirus infecting tobacco in yunnan, china. | virus isolate y3v, obtained from tobacco showing leaf curl symptoms in yunnan, china, had particles with the size and morphology typical of geminiviruses. in reactions with a set of monoclonal antibodies raised against begomoviruses, y3v was readily differentiated from two previously studied chinese begomovirus isolates. the complete nucleotide sequence of a dna-a-like molecule of y3v was determined; it comprises 2744 nucleotides and has a typical begomovirus genome organization. when compared w ... | 2001 | 11676420 |
| a unique virus complex causes ageratum yellow vein disease. | ageratum conyzoides l., a weed species widely distributed throughout southeast asia, frequently exhibits striking yellow vein symptoms associated with infection by ageratum yellow vein virus (ayvv), a member of the geminiviridae (genus begomovirus). most begomoviruses have bipartite genomes (dnas a and b), but only a dna a has been identified for ayvv. we demonstrate that yellow vein disease of a. conyzoides results from co-infection by ayvv dna a (2,741 nt) and a circular dna that is approximat ... | 2000 | 10841581 |
| complete nucleotide sequence and the genome organization of tobacco leaf curl geminivirus from japan. | the genomic dna of tobacco leaf curl geminivirus (tlcv) from tomato plants with leaf curl disease in japan has been sequenced. the single circular dna molecule comprises 2,761 nucleotides. tlcv dna contains six open reading frames (orfs) capable of encoding proteins with a molecular weight greater than 10 k. in total nucleotide sequence comparisons with other geminiviruses, tlcv was most closely related to tomato leaf curl virus from taiwan (twtolcv) (76% identity), tomato leaf curl virus from b ... | 1999 | 10585147 |
| a nanovirus-like dna component associated with yellow vein disease of ageratum conyzoides: evidence for interfamilial recombination between plant dna viruses. | yellow vein disease of ageratum conyzoides, a weed species that is widely distributed throughout asia, has been attributed to infection by the geminivirus ageratum yellow vein virus (ayvv). in addition to a single ayvv genomic component (dna a), we have previously demonstrated that infected plants contain chimeric defective viral components, comprising dna a and nongeminiviral sequences, that act as defective interfering dnas. a database search has revealed that the nongeminiviral sequences of o ... | 1999 | 10544139 |
| novel defective interfering dnas associated with ageratum yellow vein geminivirus infection of ageratum conyzoides. | defective dna forms of the geminivirus ageratum yellow vein virus (ayvv) have been identified in naturally infected ageratum conyzoides plants. several examples of the defective dna have been cloned from purified virus-specific supercoiled dna and characterized by sequence analysis. all are approximately half the size of ayvv genomic dna, and all contain intergenic region sequences and the 5' terminus of gene c1 as well as additional sequences that are unrelated to the viral genomic dna. the chi ... | 1997 | 9426449 |
| pathogenicity of a natural recombinant associated with ageratum yellow vein disease: implications for geminivirus evolution and disease aetiology. | yellow vein disease of ageratum conyzoides is caused by a viral dna complex consisting of the genomic component (dna a) of the monopartite begomovirus ageratum yellow vein virus (ayvv, family: geminiviridae) and a small satellite-like dna beta component. ayvv dna a is unable to induce symptoms in this host alone but can systemically infect a. conyzoides in which it accumulates to low levels. here, we demonstrate that the yellow vein phenotype can also be produced by co-inoculating a. conyzoides ... | 2001 | 11259188 |
| subviral dnas associated with geminivirus disease complexes. | ageratum conyzoides (ageratum) is a common and widespread weed species that may act as a reservoir host for geminivirus diseases. ageratum plants growing in singapore and exhibiting yellow vein disease are infected with a complex mixture of viral, subviral and recombinant dna components. this whitefly-transmitted disease is caused by the monopartite begomovirus ageratum yellow vein virus (ayvv) in association with a recently discovered satellite component referred to as dna beta. diseased plants ... | 2004 | 14741124 |
| a begomovirus associated with ageratum yellow vein disease in indonesia: evidence for natural recombination between tomato leaf curl java virus and ageratum yellow vein virus-[java]. | a begomovirus (2747 nucleotides) and a satellite dna beta component (1360 nucleotides) have been isolated from ageratum conyzoides l. plants with yellow vein symptoms growing in java, indonesia. the begomovirus is most closely related to tomato leaf curl java virus (tolcjv) (91 and 98% in the total nucleotide and coat protein amino acid sequences, respectively), although the products of orfs c1 and c4 are more closely related to those of ageratum yellow vein virus-[java] (91 and 95% identity, re ... | 2007 | 17294343 |
| ageratum yellow vein china virus is a distinct begomovirus species associated with a dnabeta molecule. | abstract ageratum conyzoides plants exhibiting yellow vein symptoms, collected near haikou, hainan province, china, contained begomoviral dna-a-like molecules. the complete sequences of the molecules from two samples, hn2 and hn2-19, were shown to consist of 2,768 and 2,748 nucelotides (nt), respectively. these sequences have more than 97% nucleotide sequence identity, but less than 86% identity with other reported begomovirus sequences. in line with the taxonomic convention for begomoviruses, h ... | 2007 | 18943280 |
| the natural occurrence of two distinct begomoviruses associated with dnabeta and a recombinant dna in a tomato plant from indonesia. | abstract two begomoviruses (java virus-1 and java virus-2), two satellite dnas (dnabeta01 and dnabeta02), and a recombinant dna (recdna) were cloned from a single tomato plant from indonesia with leaf curl symptoms, and the role of these satellite dnas in the etiology of begomovirus disease was investigated. the genome organizations of the two viruses were similar to those of other old world monopartite begomoviruses. comparison of the sequences with other begomoviruses revealed that java virus- ... | 2006 | 18944312 |
| complete nucleotide sequence of a monopartite begomovirus and associated satellites infecting carica papaya in nepal. | carica papaya (papaya) is a fruit crop that is cultivated mostly in kitchen gardens throughout nepal. leaf samples of c. papaya plants with leaf curling, vein darkening, vein thickening, and a reduction in leaf size were collected from a garden in darai village, rampur, nepal in 2010. full-length clones of a monopartite begomovirus, a betasatellite and an alphasatellite were isolated. the complete nucleotide sequence of the begomovirus showed the arrangement of genes typical of old world begomov ... | 2013 | 23397078 |
| molecular characterization of a novel monopartite begomovirus isolated from pouzolzia zeylanica in china. | the complete genome sequence of a monopartite begomovirus isolate ty01 was obtained from diseased pouzolzia zeylanica plants exhibiting golden mosaic symptoms in baise, guangxi province, china. it consisted of 2723 nucleotides (nt) and encoded two orfs (cp and av2) in the virion-sense dna and five orfs (ac1-ac5) in the complementary-sense dna. compared with the dna-a sequences of other begomoviruses, it has the highest (78.5 %) nucleotide sequence identity with ageratum yellow vein virus (ayvv) ... | 2013 | 23462887 |
| a novel prokaryotic promoter identified in the genome of some monopartite begomoviruses. | geminiviruses are known to exhibit both prokaryotic and eukaryotic features in their genomes, with the ability to express their genes and even replicate in bacterial cells. we have demonstrated previously the existence of unit-length single-stranded circular dnas of ageratum yellow vein virus (ayvv, a species in the genus begomovirus, family geminiviridae) in escherichia coli cells, which prompted our search for unknown prokaryotic functions in the begomovirus genomes. by using a promoter trappi ... | 2013 | 23936138 |
| association of an alphasatellite with tomato yellow leaf curl virus and ageratum yellow vein virus in japan is suggestive of a recent introduction. | samples were collected in 2011 from tomato plants exhibiting typical tomato leaf curl disease symptoms in the vicinity of komae, japan. pcr mediated amplification, cloning and sequencing of all begomovirus components from two plants from different fields showed the plants to be infected by tomato yellow leaf curl virus (tylcv) and ageratum yellow vein virus (ayvv). both viruses have previously been shown to be present in japan, although this is the first identification of ayvv on mainland japan; ... | 2014 | 24424499 |
| generation of marker-free transgenic plants concurrently resistant to a dna geminivirus and a rna tospovirus. | global threats of ssdna geminivirus and ss(-)rna tospovirus on crops necessitate the development of transgenic resistance. here, we constructed a two-t dna vector carrying a hairpin of the intergenic region (igr) of ageratum yellow vein virus (ayvv), residing in an intron inserted in an untranslatable nucleocapsid protein (np) fragment of melon yellow spot virus (mysv). transgenic tobacco lines highly resistant to ayvv and mysv were generated. accumulation of 24-nt sirna, higher methylation leve ... | 2014 | 25030413 |
| characterization of the cryptic av3 promoter of ageratum yellow vein virus in prokaryotic and eukaryotic systems. | a cryptic prokaryotic promoter, designated av3 promoter, has been previously identified in certain begomovirus genus, including ageratum yellow vein virus isolate nt (ayvv-nt). in this study, we demonstrated that the core nucleotides in the putative -10 and -35 boxes are necessary but not sufficient for promoter activity in escherichia coli, and showed that ayvv-nt av3 promoter could specifically interact with single-stranded dna-binding protein and sigma 70 of e. coli involved in transcription. ... | 2014 | 25268755 |
| ageratum conyzoides: a host to a unique begomovirus disease complex in cameroon. | ageratum conyzoides (goat weed) is a widespread uncultivated species in cameroon that exhibits leaf curl disease (lcd) symptoms suggestive of begomovirus infection. in asia, different begomovirus-satellite complexes have been identified in a. conyzoides. the objective of this study was to determine the identity of the suspect begomoviruses and their associated satellites in a. conyzoides in cameroon. the results indicated that all three symptomatic a. conyzoides plants examined were infected wit ... | 2011 | 22001569 |
| identification of the virulence factors and suppressors of posttranscriptional gene silencing encoded by ageratum yellow vein virus, a monopartite begomovirus. | ageratum yellow vein disease (ayvd) is caused by the association of a tomato leaf curl java betasatellite [indonesia:indonesia 1:2003] (tolcjb-[id:id1:03]) with a begomovirus component. our previous results demonstrated that tolcjb-[id:id:03] is essential for induction of leaf curl symptoms in plants and transgene expression of its betac1 gene in nicotiana benthamiana plants induces virus-like symptoms. here we show that ageratum yellow vein virus-indonesia [indonesia: tomato] (ayvv-id[id:tom]) ... | 2010 | 20079777 |
| genome organization of ageratum yellow vein virus, a monopartite whitefly-transmitted geminivirus isolated from a common weed. | a full-length copy of a single genomic component of the whitefly-transmitted geminivirus ageratum yellow vein virus (ayvv) has been cloned from an extract of infected ageratum conyzoides originating from singapore. sequence analysis shows that the genomic component encodes two virion-sense (v1 and v2) and four complementary-sense open reading frames (c1-c4), typical of dna a of whitefly-transmitted geminiviruses from the eastern hemisphere. a genomic component equivalent to dna b was not detecte ... | 1995 | 8847495 |