First complete genome sequence of an isolate of cowpea severe mosaic virus from South America

Virus Genes. 2021 Apr;57(2):238-241. doi: 10.1007/s11262-021-01831-2. Epub 2021 Feb 8.

Abstract

In this study, the complete nucleotide sequence of a Brazilian isolate of cowpea severe mosaic virus (CPSMV) is presented for the first time. To date, the CPSMV-DG isolate, from the USA, is the only one with the complete known genome. High-throughput sequencing (Illumina HiSeq) and Sanger sequencing of the total RNA extract from a cowpea plant collected in Teresina city, Brazil, revealed the genome sequence of the CPSMV-Ter1 isolate. RNA-1 and RNA-2 are, respectively, 5921 and 3465 nucleotides (nt) long without the poly(A) tail, and show 77.91% and 76.08% nt sequence identity with CPSMV-DG, considered the type isolate of the species. The open reading frames (ORFs) were determined and the cleavage sites of the polyproteins were predicted. Although the two isolates show a similar genomic organization, there was a low percentage of sequence identity between Ter1 and DG. Furthermore, pairwise comparisons of a partial RNA-1 fragment between CPSMV-Ter1 and 11 CPSMV isolates from Brazil indicated 94.6 to 94.8% nt and 98.9% to 99.4% aa sequence identities.

Keywords: CPSMV; Comovirus; High-throughput sequencing; Secoviridae; Vigna unguiculata.

MeSH terms

  • Brazil
  • Comovirus / genetics*
  • Comovirus / isolation & purification
  • Genome, Viral*
  • RNA, Viral
  • Sequence Analysis, RNA
  • Vigna / virology
  • Whole Genome Sequencing

Substances

  • RNA, Viral

Supplementary concepts

  • Cowpea severe mosaic virus