A second capsidless hadakavirus strain with 10 positive-sense single-stranded RNA genomic segments from Fusarium nygamai

A unique capsidless virus with a positive-sense, single-stranded RNA genome (hadakavirus 1, HadV1), member of the extended picorna-like supergroup, was isolated previously from phytopathogenic fungus Fusarium oxysporum. Here, we describe molecular and biological characterisation second hadakavirus strain nygamai, which has not been investigated in detail as host. This virus, 1 1NL (HadV1-1NL), features similar to first hadakavirus, HadV1-7n, despite having different number segments (10 for HadV1-1NL vs. 11 HadV1-7n). The 10 genomic range size 0.9 kb 2.5 kb. All show 67% 86% local nucleotide sequence identity their HadV1-7n counterparts, whereas no homolog RNA8, encodes zinc-finger motif. Another interesting feature is possible coding incapability RNA10. predicted be based on RNase susceptibility its replicative form dsRNA. Phenotypic comparison multiple virus-infected virus-free single-spore isolates indicated asymptomatic infection by HadV1-1NL. Less-efficient vertical transmission via spores observed infected fungal colonies were derived became older, HadV1-7n. study shows example that appears have unusual features.