Molecular analysis of three new Cherry mottle leaf virus isolates reveals intra-species genetic diversity and inter-species gene transfer

Abstract

Cherry mottle leaf virus (CMLV) is a pathogen of sweet cherry and several other plant species in the genus Prunus, but only two isolates of the virus were reported previously. Here we determined the complete genome sequences of three CMLV isolates that were collected during 1980s. The coat protein of the CMLV was estimated to be about 22 kDa by protein western blot assay, and agree with the size expected based on their genome sequences. The three isolates share 78.4 to 82.7 % identities at the nucleotide sequence level between each other and 78.7 to 84.3 % identities to the two previously published CMLV isolates SA1162-21 and 95CI215. The high genome sequence divergences among the CMLV isolates were supported by phylogeny analysis. Possible inter-species gene transfer between CMLV and the other species in the genus Trichovirus was revealed by the RDP recombination analysis algorithms.