title: Novel mitoviruses in Rhizoctonia solani AG-3PT infecting potato.
abstract: Double-stranded RNA (dsRNA) elements are ubiquitous in Rhizoctonia solani. Total dsRNA was randomly amplified from a R. solani isolate (RS002) belonging to anastomosis group-3PT (AG-3PT), associated with black scurf in potato. Assembly of resulting cDNA sequences identified a nearly complete genome of a novel virus related to the genus Mitovirus (family Narnaviridae), herein named Rhizoctonia mitovirus 1 RS002 (RMV-1-RS002). The 2797 nucleotide partial genome of RMV-1-RS002 is A-U rich (59.06 %), and can be folded into stable stem-loop structures at 5' and 3' ends. Universal and mold mitochondrial codon usages revealed a large open reading frame in the genome, putatively encoding an 826 amino acid polypeptide, which has conserved motifs for mitoviral RNA-dependent RNA polymerase. The full length putative polypeptide shared 25.6 % sequence identity with the corresponding region of Tuber excavatum mitovirus (TeMV). The partial genome of a second mitovirus (proposed name Rhizoctonia mitovirus 2 RS002 (RMV-2-RS002)) was also amplified from RS002. A nearly identical copy of RMV-1-RS002 was detected in two additional AG-3PT isolates. These data indicate that multiple mitoviruses can exist in a single isolate of R. solani AG-3PT, and that mitoviruses such as RMV-1-RS002 are probably widespread in this pathogen. The roles of mitoviruses in the biology of R. solani AG-3PT remain unknown.
authors.affiliation: Bio-Protection Research Centre, PO Box 85084, Lincoln University 7647, New Zealand; The New Zealand Institute for Plant & Food Research Limited, PB 4704, Christchurch, New Zealand. Electronic address: subhadas1981@gmail.com.
authors.forename: Subha
authors.initials: S
authors.lastname: Das
authors.affiliation: Bio-Protection Research Centre, PO Box 85084, Lincoln University 7647, New Zealand; The New Zealand Institute for Plant & Food Research Limited, PB 4704, Christchurch, New Zealand. Electronic address: richard.falloon@plantandfood.co.nz.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Falloon
authors.affiliation: Bio-Protection Research Centre, PO Box 85084, Lincoln University 7647, New Zealand; Scion, Te Papa Tipu Innovation Park, 49 Sala Street, Private Bag 3020, Rotorua 3046, New Zealand. Electronic address: alison.stewart@scionresearch.com.
authors.forename: Alison
authors.initials: A
authors.lastname: Stewart
authors.affiliation: Bio-Protection Research Centre, PO Box 85084, Lincoln University 7647, New Zealand; The New Zealand Institute for Plant & Food Research Limited, PB 4704, Christchurch, New Zealand. Electronic address: andrew.pitman@plantandfood.co.nz.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Pitman
mesh_terms: D016679:Genome, Viral; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D012328:RNA Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics; D012232:Rhizoctonia / Q000302:isolation & purification* / Q000821:virology*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D011198:Solanum tuberosum / Q000382:microbiology*
chemical_list: D012367:RNA, Viral; D012324:RNA-Dependent RNA Polymerase
keywords: Double-stranded RNA (dsRNA); Hypovirulence; Mycovirus; Narnaviridae; RNA-dependent RNA polymerase (RdRp)