RESUMEN
Aplosporella javeedii is a pathogenic fungus that causes canker and dieback of jujube in China. In this study, we report a new mycovirus, Aplosporella javeedii partitivirus 1 (AjPV1), isolated from A. javeedii strain NX55-3. The AjPV1 genome contains two double-stranded RNA elements (dsRNA1 and dsRNA2). The size of dsRNA1 is 2,360 bp, and it encodes a putative RNA-dependent RNA polymerase (RdRp), while dsRNA2 is 2,301 bp in length and encodes a putative capsid protein (CP). The sequences of RdRp and CP have significant similarity to those of members of the family Partitiviridae. Sequence alignment and phylogenetic analysis showed that AjPV1 is a new member of the family Partitiviridae that is related to members of the genus Betapartitivirus. To our knowledge, AjPV1 is the first mycovirus reported from A. javeedii.
Asunto(s)
Ascomicetos/virología , Virus ARN Bicatenario/genética , Virus Fúngicos/genética , Enfermedades de las Plantas/microbiología , Secuencia de Aminoácidos , Secuencia de Bases , Virus ARN Bicatenario/clasificación , Virus ARN Bicatenario/aislamiento & purificación , Virus Fúngicos/clasificación , Virus Fúngicos/aislamiento & purificación , Genoma Viral/genética , Filogenia , Enfermedades de las Plantas/virología , ARN Viral/genética , Proteínas Virales/genética , Ziziphus/microbiología , Ziziphus/virologíaRESUMEN
Chinese jujube (Ziziphus jujuba Mill.) is a native fruit crop in China. Leaf mottle and dapple fruit disease is prevalent in cultivated jujube plants grown at Aksu in Xinjiang Uygur Autonomous Region of China. Jujube yellow mottle-associated virus (JYMaV), a tentative member in the genus Emaravirus, was recently identified from mottle-diseased jujube plants grown in Liaoning Province in China, but its incidence and genetic diversity in China is unknown. In this study, the genome sequences of three JYMaV isolates from two jujube cultivars and one jujube variant were determined by high-throughput sequencing (HTS) for small RNA and rRNA-depleted RNA coupled with RT-PCR assays. Comparison of these sequences together with sequences of the viral RNA segments derived by primer set 3C/5H-based RT-PCR revealed that genetic diversity was present in the virus populations and high sequence variation occurred at the non-translational regions of each of the viral genomic segments. Field investigation confirmed the close association of the virus with leaf mottle symptoms of jujube plants. Furthermore, this study revealed that P5 encoded in the viral RNA5 displayed a nuclear localization feature differing from the plasmodesma (PD) subcellular localization of the virus movement protein (P4), and the two proteins could interact with each other in the BiFC assays. Our study provides a snapshot of JYMaV genetic diversity in its natural hosts.
Asunto(s)
Bunyaviridae/clasificación , Bunyaviridae/genética , Ziziphus/virología , Bunyaviridae/aislamiento & purificación , Bunyaviridae/ultraestructura , China , Variación Genética , Genoma Viral , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Sistemas de Lectura Abierta , Fenotipo , Filogenia , Enfermedades de las Plantas/virología , Hojas de la Planta/virología , Virus ARN/genética , ARN Viral , Análisis de Secuencia de ARNRESUMEN
We report a new circular DNA virus identified from a Chinese jujube tree showing mosaic-like symptoms. The genome of this virus is 7194 bp in length and contains five putative open reading frames (ORFs), all on the plus-strand of the genome. The genomic organization, primer binding sites and the sizes of the ORFs were similar to those reported for other badnaviruses (family Caulimoviridae), except for ORF3, which was split into ORF3a and ORF3b with a 70-nt intergenic region. Furthermore, this new virus shares low nucleotide sequence identity (<50%) with other members of the family Caulimoviridae. Consequently, we propose this virus as a new member of the family Caulimoviridae and refer to it as jujube mosaic-associated virus (JuMaV).