Complete genome sequence of a novel endornavirus from Rhizoctonia solani AG-1 IA isolate MY-JK-1

Area of Science:

• Mycology
• Virology
• Plant Pathology

Background:

• Rhizoctonia solani is a significant plant pathogen.
• Fungal viruses, including endornaviruses, can influence host physiology and pathogenicity.
• The diversity and evolutionary relationships of fungal viruses are not fully understood.

Purpose of the Study:

• To report the discovery and initial characterization of a novel fungal virus.
• To determine the genomic features and phylogenetic placement of the new virus.
• To investigate its relationship with other known endornaviruses.

Main Methods:

• Isolation of the virus from Rhizoctonia solani AG-1 IA strain MY-JK-1.
• Whole-genome sequencing and analysis of the viral genome.
• Bioinformatic analysis including ORF prediction, domain identification, and BLASTp.
• Phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) sequences.

Main Results:

• A novel fungal virus, tentatively named Rhizoctonia solani endornavirus 15 (RsEV15), was isolated.
• RsEV15 possesses an 18,934-nucleotide genome with a GC content of 44.5% and two open reading frames (ORFs).
• ORF1 encodes a protein with RNA-dependent RNA polymerase (RdRp), helicase (Hel), and glycosyltransferase domains; ORF2 encodes a protein of unknown function.
• Phylogenetic analysis places RsEV15 within the genus Alphaendornavirus, family Endornaviridae, showing a distant relationship to RsEV8.

Conclusions:

• RsEV15 represents a new species within the genus Alphaendornavirus.
• The genomic features of RsEV15 provide insights into the diversity of fungal endornaviruses.
• Further studies are warranted to understand the biological role and impact of RsEV15 on its host, Rhizoctonia solani.