Genome sequences of poa semilatent and lychnis ringspot hordeiviruses.

The nucleotide sequences of the genomic RNAs of two hordeiviruses, poa semilatent virus (PSLV) and lychnis ringspot virus (LRSV), were determined. The genome organization of both viruses is similar to that of the type hordeivirus, barley stripe mosaic virus (BSMV). Comparisons of the amino acid sequences of the hordeivirus replicase components revealed a high level of sequence similarity to those of soil-borne wheat mosaic virus (SBWMV), peanut clump virus (PCV), and Indian peanut clump virus. The cysteine-rich gamma b proteins of hordeiviruses are similar to those of SBWMV, PCV, and tobraviruses. Analysis of cis-acting elements in the genomes of the three hordeiviruses revealed conservation of putative core elements of subgenomic RNA promoters. Complex patterns of conservation were also found in the 5'-untranslated regions of hordeivirus genomic RNAs alpha, beta, and gamma.