Genomic Relationships between Rice Black-streaked Dwarf and Maize Rough Dwarf Fijiviruses Detected by Nucleic Acid Hybridization.

Abstract

By polyacrylamide gel electrophoresis (PAGE) and nucleic acid hybridization, the extent of genomic relatedness between rice black-streaked dwarf Fijivirus (RBSDV) and maize rough dwarf Fijivirus (MRDV) was investigated. It was previously reported that RBSDV S7 and S8 correspond to MRDV S6 and S7, respectively, based on nucleotide sequences (Marzachi et al., Virology, 1991). However, present comparison of the genomic segments of the two viruses in polyacrylamide gel electrophoresis together with the hybridization studies with the cDNA probes showed correspondence of the two virus segments as RBSDV S7-MRDV S7 and RBSDV S8-MRDV S8. Hybridization studies using cDNAs to all the RBSDV segments except for S3 as a probe showed that extent of sequence relatedness was found to differ among the segments. Partial cDNA clones to RBSDV S1, S4, S5and S6 reacted substantially weaker to MRDV genome than those to the other segments tested. And the cDNAs to the RBSDV S5 and S6 were found to be useful to differentiate the two viruses.

Detection and assignment of proteins encoded by rice black streaked dwarf fijivirus S7, S8, S9 and S10.

“…Prehybridization and hybridization were performed using the method described by Isogai et al (1995).…”

Genomic and phylogenetic evidence that Maize rough dwarf and Rice black-streaked dwarf fijiviruses should be classified as different geographic strains of a single species

“…During the preparation of this manuscript, the partial S1-S10 genomic sequences of a Spanish isolate of MRDV were also made public (accession numbers LK392325-LK392343; Achon et al, 2015). Th e Italian and Spanish isolates share more than 95% identities with each other at both the nucleotide and amino acid levels and S7-S10 of both isolates share 95.6-99.7% nucleotide and amino acid identities with the partial sequences of the isolates previously described by Marzachi et al (1991Marzachi et al ( , 1995, although those earlier sequences appear to be wrongly labelled: those labelled S6 and S7 should be reassigned as S7 and S8, respectively, as fi rst proposed by Isogai et al (1995) on the basis of hybridization experiments.…”

“…All known fi jiviruses contain ten linear genomic segments of double-stranded RNA (dsRNA), ranging in size from approximately 1.4 to 4.5 kb and named S1-10 according to their migration in PAGE, and most of them replicate in their plant hosts, where they induce growth abnormalities. Previous extensive studies have shown that the four viral pathogens of MRDD are closely related to each other and similar in particle morphology, genomic profi le, and serological relationships (Luisoni et al, 1973;Milne et al, 1973Milne et al, , 1977aReddy et al, 1975Reddy et al, , 1983Isogai et al, 1995;Zhang et al, 2001a,b;Distéfano et al, 2002Distéfano et al, , 2003Distéfano et al, , 2005Distéfano et al, , 2009Guzmán et al, 2007, Wang et al, 2010. All these viruses naturally infect maize and cause similar symptoms on maize or other host plants (Milne et al, 1977a;Attoui et al, 2012).…”

“…(3) MRDV is transmitted through the eggs of its vector insect but RB-SDV is not (Harpaz and Klein 1969;Harpaz, 1972;Milne et al, 1977a). (4) Serological comparisons and hybridization experiments using cDNA probes also suggest that they are distinct viruses (Isogai et al, 1995;Marzachi et al, 1995). (5) Th e complete genomes of at least one isolate of MRCV, RBSDV, and SRBSDV have been determined and comparisons support the view that these three fi jiviruses, at least, should continue to be members of distinct species (Zhang et al, 2001a;Guzmán et al, 2007;Wang et al, 2010;Xue et al, 2014).…”

Complete Genomic Sequence of Maize Rough Dwarf Virus, a Fijivirus Transmitted by the Small Brown Planthopper

“…S1 contained the major motifs characteristic of an RNA-dependent RNA polymerase (RdRp) (10), which can be aligned with those from the RdRp proteins of other reoviruses and which is thought to be a minor component of the core particle. RBSDV, MRDV, RBSDV-2, and MRCV were always closely clustered together in phylogenetic analyses of their segments, and the new sequences of MRDV will be important for determining the appropriate taxonomic positions of these viruses, which sometimes have been considered isolates of a single species (11). …”