RESUMO
Apple mosaic virus (ApMV) is a widespread ssRNA virus which infects diverse species of Rosales. The phylogenetic analysis of complete capsid protein gene of the largest set of ApMV isolates discriminated two main clusters of isolates: one cluster correlates with Maloideae hosts and Trebouxia lichen algae hosts; a second with hop, Prunus, and other woody tree hosts. No correlation was found between clusters and geographic origin of virus isolates, and positive selection hypothesis in distinct hosts was not confirmed: in all virus populations, purifying selection had occurred. GGTâAAT substitution resulted in GlyâAsn change inside the zinc-finger motif in the capsid protein was revealed specific for discrimination of the clusters and we hypothesise that could influence the host preference.
Assuntos
Proteínas do Capsídeo/genética , Variação Genética , Especificidade de Hospedeiro , Ilarvirus/genética , Malus/virologia , Doenças das Plantas/virologia , Sequência de Aminoácidos , Ilarvirus/classificação , Ilarvirus/isolamento & purificação , Ilarvirus/fisiologia , Dados de Sequência Molecular , FilogeniaRESUMO
Daphne shrubs with light green rings and mosaic on leaves contained flexuous filamentous virions (696 x 13 nm) and cylindrical inclusions typical of the subdivision III of Edwardson's classification for inclusions induced by members of the family Potyviridae. Decoration tests using antisera to 67 potyviruses revealed distant serological relations among chilli veinal mottle virus, Colombian datura virus, papaya ringspot virus, tobacco vein mottling virus and yam mosaic virus. The 3' terminal region of the virus genome was amplified by RT-PCR using primers specific for cloned and sequenced members of the family Potyviridae. The most similar sequences in the GenBank were those of isolates of wild potato mosaic virus (WPMV) and yam mild mosaic virus (YMMV), originating from Peru and Guadeloupe, respectively. The new sequence had 63.2% and 61.9% nucleotide identity to WPMV and YMMV in the coat protein gene. The results suggest that the Czech isolate from daphne should be regarded as a new member of the genus Potyvirus. The name daphne mosaic virus (DapMV) is suggested for this virus.
Assuntos
Daphne/virologia , Potyvirus/classificação , Proteínas do Capsídeo/genética , República Tcheca , Genoma Viral , Dados de Sequência Molecular , Folhas de Planta/virologia , Potyvirus/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da EspécieRESUMO
The 3'-terminal part of RNA1 genome segment of Radish mosaic virus (RaMV) including complete RNA polymerase gene was sequenced. The 207 amino acids long polymerase is matured from a polyprotein precursor by cleavage at putative Q/H site by viral protease. The alignment of available amino acid sequences of RNA polymerase genes of comoviruses revealed a closest (55%) identity of RaMV to Red clover mottle virus (RCMV).
Assuntos
Comovirus/genética , RNA Polimerases Dirigidas por DNA/genética , Vírus do Mosaico/genética , RNA Viral/genética , Raphanus/genética , Raphanus/virologia , Sequência de Aminoácidos , Sequência Conservada , Dados de Sequência Molecular , Filogenia , Plantas Medicinais , Análise de Sequência de RNA , Homologia de Sequência de AminoácidosAssuntos
Anticorpos Antivirais/imunologia , Caulimovirus/imunologia , Ensaio de Imunoadsorção Enzimática , Doenças das Plantas/virologia , Proteínas do Envelope Viral/imunologia , Animais , Caulimovirus/genética , Caulimovirus/isolamento & purificação , Fragaria/virologia , Frutas/virologia , Coelhos , Proteínas Recombinantes/genética , Proteínas do Envelope Viral/genéticaRESUMO
Eight new sequences of European isolates from almond, apple, hop, prune and pear of the Apple mosaic ilarvirus (ApMV) capsid protein gene are presented. A consensus sequence was established as having 654 nucleotides (nt) and two American and two European isolates were identified to have insertions 6 to 15 nucleotides after nt position 141. The insertion resulted in the American isolate A inframeshift repaired with two point insertions 17 and 68 nt downstream. The RNA around the insertion point can potentially form a stable secondary structure with three hairpins. The insertions could stabilise this structure or could be neutral. The predicted folding of the translated protein is not influenced by the insertions or frameshift, and we speculate that the region after nt position 141 is without reasonable selection pressure and represents a hot spot for the accumulation of insertion mutations in ApMV.
Assuntos
Capsídeo/genética , Genes Virais , Ilarvirus/genética , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/química , Europa (Continente) , Variação Genética , Humulus/virologia , Ilarvirus/química , Malus/virologia , Dados de Sequência Molecular , Mutagênese Insercional , Conformação de Ácido Nucleico , Estrutura Secundária de Proteína , Prunus/virologia , RNA Viral/química , Alinhamento de SequênciaRESUMO
The coat protein (CP) gene of Prunus necrotic ringspot virus (PNRSV) was cloned into pET 16b vector and expressed in Escherichia coli. CP-enriched fractions were prepared from whole cell lysate by differential centrifugation. The fraction sedimenting at 20,000 x g for 30 mins was used for preparation of a rabbit antiserum to CP. This antiserum had a titer of 1:2048 and reacted in a double-antibody sandwich ELISA (DAS-ELISA).
Assuntos
Capsídeo/isolamento & purificação , Ilarvirus/genética , Sequência de Bases , Capsídeo/genética , Clonagem Molecular , Genes Virais , Ilarvirus/isolamento & purificação , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Árvores/virologiaRESUMO
The 3'-part of the movement protein gene, the intergenic region and the complete coat protein gene of sixteen isolates of Prunus necrotic ringspot virus (PNRSV) from five different host species from the Czech Republic were sequenced in order to search for the bases of extensive variability of viroses caused by this pathogen. According to phylogenetic analyses all the 46 isolates sequenced to date split into three main groups, which correlated to a certain extend with their geographic origin. Modelled serological properties showed that all the new isolates belong to one serotype.
Assuntos
Ilarvirus/classificação , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/análise , Capsídeo/química , Ilarvirus/genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Proteínas do Movimento Viral em Plantas , Proteínas Virais/genéticaRESUMO
Thirteen cultivars of hop (Humulus lupulus L.) were tested by reverse transcription-polymerase chain reaction (RT-PCR) for the presence of apple mosaic virus (ApMV). The virus was detected in various amounts in all tested cultivars. Control hop clones derived from tissue cultures, treated by thermotherapy and maintained in greenhouse were virus-free. The procedure for sample preparation and RT-PCR of ApMV is described in detail.
Assuntos
Ilarvirus/genética , Doenças das Plantas/virologia , Plantas/virologia , RNA Viral/análise , Sequência de Bases , República Tcheca , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodosRESUMO
Scrophularia mottle virus (ScMV) was newly found in the Czech Republic in Scrophularia nodosa L. plants. The Czech isolate (ScMV-C) was serologically identical and similar in symptoms and host range to the Italian Anagyris strain (ScMV-I). Nicotiana tabacum L. cv. Samsun, Nicotiana glutinosa L., Nicotiana tabacum L. cv. White Burley, Physalis floridana Rybd. and Cucumis sativus L. are described as new host plants of ScMV. Double-stranded RNA patterns and the isoelectric point of this virus are characterized.