Complete nucleotide sequence of four RNA segments of fig mosaic virus

Abstract

The complete sequence of four viral RNA segments of fig mosaic virus (FMV) was determined. Each of the four RNAs comprises a single open reading frame (ORF) 7,093, 2,252, 1,490 and 1,472 nucleotides in size, respectively. These ORFs encode the following proteins in the order: RNA-dependent RNA polymerase (p1 264 kDa), a putative glycoprotein (p2 73 kDa), a putative nucleocapsid protein (p3 35 kDa) and a protein with unknown function (p4 40.5 kDa). All RNA segments possess untranslated regions containing at the 5' and 3' termini a 13-nt complementary sequence. A conserved motif denoted premotif A was found to be present in addition to the five RdRp motifs A-F in RNA-1. In phylogenetic trees constructed with the amino acid sequences of RNA-1 and RNA-2, FMV clustered consistently with European mountain ash ringspot-associated virus (EMARaV) in a clade close to those comprising members of the genera Hantavirus, Orthobunyavirus and Tospovirus. The amino acid sequence of the putative FMV nucleocapsid protein encoded by RNA-3 shared identity with comparable sequences of EMARaV and the unclassified viruses pigeonpea sterility mosaic virus (PPSMV) and maize red stripe virus (MRSV). The nucleocapsid sequences rooted the four viruses in a clade close to the genus Tospovirus. Based on molecular, morphological and epidemiological features, FMV appears to be very closely related to PPSMV and MRSV. All these viruses are phylogenetically related to EMARaV and therefore seem to be eligible for classification in the proposed genus Emaravirus, which, in turn, may find a taxonomic allocation in the family Bunyaviridae.

Emaravirus-specific degenerate PCR primers allowed the identification of partial RNA-dependent RNA polymerase sequences of Maize red stripe virus and Pigeonpea sterility mosaic virus

“…Comparison of the nucleotides and predicted amino acid sequence of all RNA segments of Emaravirus-like viruses with their homologue showed that RNA1 is the most conserved segments among all others analyzed, for which that of FMV, EMARaV, RLBV, RRV and RYRV revealed the presence of five highly conserved regions denoted as motifs (A-E) in the RdRp gene, similarly to what has been previously reported with FMV and EMARaV by Elbeaino et al, (2009aElbeaino et al, ( , 2009b. Computer-assisted analysis showed that among all five analyzed regions, the pre-motif A, motifs A and C were the most conserved ones (data not shown) (Fig.…”

“…The genus deems its' acronym to the European mountain ash ringspot-associated virus (EMARaV), firstly identified and is the type species of this genus, which has a genome composed of four RNA segments (Mielke and Muehlbach, 2007). Fig mosaic virus (FMV) is an another approved species (Adams and Carstens, 2012) of the recently established genus Emaravirus with a genome composed of six single-stranded negative-sense RNA that has recently been recognised as the causal agent of fig mosaic disease (FMD) (Elbeaino et al, 2009a;2009b. Intracellular DMBs were identified as particles of the putative causal agents of fig mosaic and of the ringspot disease of European mountain ash (Mielke and Muehlbach, 2007;Elbeaino et al, 2009a;2009b).…”

“…Fig mosaic virus (FMV) is an another approved species (Adams and Carstens, 2012) of the recently established genus Emaravirus with a genome composed of six single-stranded negative-sense RNA that has recently been recognised as the causal agent of fig mosaic disease (FMD) (Elbeaino et al, 2009a;2009b. Intracellular DMBs were identified as particles of the putative causal agents of fig mosaic and of the ringspot disease of European mountain ash (Mielke and Muehlbach, 2007;Elbeaino et al, 2009a;2009b). In addition, the same structures were also observed in infected cells of mosaic-diseased plants of pigeonpea (Cajanus cajan L.), maize (Zea mays L.) and wheat (Triticum aestivum L.), thought to be induced by Pigeonpea sterility mosaic virus (PPSMV) and Maize red stripe virus (MRSV) (Kumar et al, 2002;Ahn et al, 1998;Jensen et al, 1996).…”

“…Members of genus Emaravirus, an unassigned genus to any family of plant viruses, share some distant similarities with viruses belonging to the family Bunyaviridae and the genus Tenuivirus (Elbeaino et al, 2009a(Elbeaino et al, , 2009b. However, the number of genome segments (at least four) distinguishes the genus Emaravirus from bunyaviruses and sequence analyses do not allow classification within either the family Bunyaviridae or the genus Tenuivirus (Muehlbach and Mielke-Ehret, 2011).…”

Experimental and bioinformatic evidence that raspberry leaf blotch emaravirus P4 is a movement protein of the 30K superfamily

“…Thus, EMARAV and rose rosette virus (RRV) are reported to have four genomic RNA segments (Mielke & Muehlbach, 2007;Laney et al, 2011). Fig mosaic virus (FMV) was initially reported also to have four RNAs, which have now been supplemented by another two (Elbeaino et al, 2009;Ishikawa et al, 2012). RLBV was reported initially to have five RNA segments but is now known to have at least eight (McGavin et al, 2012;S.…”