Complete Genome Analysis of a Novel Picorna-Like Virus From a Ladybird Beetle, Cheilomenes Sexmaculata

Abstract The ladybird beetle Cheilomenes sexmaculata (family Coccinellidae, order Coleoptera), is a common insect predator of agricultural pests. In this study, the full genome sequence of a novel picorna-like virus, temporarily named “Cheilomenes sexmaculata picorna-like virus 1” (CSPLV1), was identified from C. sexmaculata. The full-length sequence of CSPLV1 was 11,384 nucleotide (nt) in length (excluding the polyA tail) with one predicted open reading frame (ORF) encoding 3727 amino acids, a 13 nt 5' untranslated region (UTR) and a 187 nt 3' UTR. The ORF of CSPLV1 consisted of four distinct domains including an RNA virus helicase domain (3029-3319 nt), a peptidase domain (5555-6121 nt), an RNA-dependent RNA polymerase domain (7154-8101 nt) and a picorna-like coat protein domain (8606-9283nt). Phylogenetic analysis based on the conserved RdRP sequence showed that CSPLV1, together with Wuhan house centipede virus 3, Hypera postica associated virus 1 and Diabrotica undecimpunctata virus 1, formed as an unclassified group which is closely related to the clade Solinviviridae. To the best of our knowledge, CSPLV1 is the first picorna-like virus revealed in C. sexmaculata.