ABSTRACT
The genomic sequences of Plantago asiatica mosaic virus (PlAMV), six lily isolates and one primrose isolate from Japan, were determined. The genomic size of all isolates was 6102 nucleotides, containing the five open reading frames typical of members of the genus Potexvirus. Pairwise comparison analyses confirmed the close relationship between PlAMV and tulip virus X. However, quite low identities were observed between different PlAMV isolates, including foreign isolates; nucleotide sequence identities of the RNA-dependent RNA polymerase (RdRp) gene between a Russian isolate (PlAMV-Ru), a Nandina isolate (PlAMV-Na) and Japanese isolates were 75-77%. These values were the lowest amongst different isolates of the same species of any potexviruses.
Subject(s)
Genes, Viral , Genome, Viral , Potexvirus/classification , Potexvirus/genetics , RNA, Viral/genetics , Base Sequence , Japan/epidemiology , Molecular Sequence Data , Open Reading Frames , Viral Proteins/chemistryABSTRACT
The complete nucleotide sequences of RNA1 and RNA2 of a Japanese isolate of Radish mosaic virus (RaMV-J), a crucifer-infecting comovirus, were determined. RNA1 is 6064 nucleotides long and encodes a 210-kDa polyprotein containing conserved motifs that are required for replication. RNA2 is 4020 nucleotides long and encodes a 123-kDa polyprotein containing the putative movement protein and two coat proteins. Comparisons of the encoded proteins confirmed that RaMV-J and a Czech RaMV isolate are isolates of the same species in the genus Comovirus. A phylogenetic analysis of RaMV-J and other comoviruses revealed that legume-infecting comoviruses constitute a single branch to which RaMV is distantly related.
Subject(s)
Comovirus/genetics , Genome, Viral , Mosaic Viruses/genetics , Raphanus/virology , Sequence Analysis, DNA , Amino Acid Sequence , Comovirus/classification , Comovirus/isolation & purification , Japan , Molecular Sequence Data , Mosaic Viruses/classification , Mosaic Viruses/isolation & purification , Phylogeny , Plant Diseases/virology , RNA, Viral/genetics , Viral Proteins/chemistry , Viral Proteins/geneticsABSTRACT
From a lily isolate of Plantago asiatica mosaic virus (PlAMV-Li), two sub-isolates (Li1 and Li6) were obtained. Although the nucleotide sequences of Li1 and Li6 were highly conserved, they showed different pathogenicity in Nicotiana benthamiana. Li1 caused necrosis, whereas Li6 infected the plant asymptomatically. Inoculation tests with chimeric and point-mutated viruses revealed that amino acid 1154 of the RNA-dependent RNA polymerase (RdRp) contributes to the necrotic symptoms. The accumulation of the mutant viruses, in which amino acid 1154 of the RdRp was exchanged to the wild-type codon in Li1 and Li6, was almost equal.
Subject(s)
Mosaic Viruses/enzymology , Mosaic Viruses/pathogenicity , Plant Diseases/virology , RNA-Dependent RNA Polymerase/genetics , Reassortant Viruses/pathogenicity , Viral Proteins/genetics , Amino Acids , Lilium/virology , Mosaic Viruses/genetics , Point Mutation , Nicotiana , Virulence/geneticsABSTRACT
Cerebella from suckling and adult rats were examined histochemically with 19 different biotin-labeled lectins. Purkinje cells from postnatal rats had a marked ability to combine with many lectins, but minimal ability was found in adult rats except for Con-A, LEL, and MAL lectins. The cell body of Purkinje cells on postnatal day 7 was strongly labeled with 6 lectins (Con-A, LTL, MAL, SJA, UEA-I, and VVA). Only moderate staining was observed with these lectins on postnatal day 5. The dendritic tree of the cells showed a moderate labeling ability with LTL and UEA-I on postnatal days 15 and 20. The dendritic tree was strongly labeled with MAL on postnatal days 10, 15, 20 and adult. Positive reactions were observed in the cells when cerebellar sections from rats on postnatal day 7 were incubated with 3 other lectins (AAL, LEL, and SBA). The cells on postnatal day 7 were rarely labeled with BSL-II, DBA, DSL, LCA, PNA, PSA, RCA120, SSA, STL, and WGA. Purkinje cells on postnatal day 7 may be rich in N-linked oligosaccharides, with terminal sugar structures that resemble blood-group-related antigens (type H) and/or tumor-related antigens. These glycoconjugates may be present at low levels in the Purkinje cells of adult rats. Dendrites of Purkinje cells of adult rats were strongly labeled by Con-A, LEL, and MAL. The dendrites of Purkinje cells may be rich in highly branched oligosaccharides.
