Intra‐strain biological and epidemiological characterization of plum pox virus. (24th January 2020)

• Record Type: Journal Article
• Authors: Maejima, Kensaku; Hashimoto, Masayoshi; Hagiwara‐Komoda, Yuka; Miyazaki, Akio; Nishikawa, Masanobu; Tokuda, Ryosuke; Kumita, Kohei; Maruyama, Noriko; Namba, Shigetou; Yamaji, Yasuyuki
• Is Part Of: Molecular plant pathology. Volume 21:Number 4(2020)
• Page Start: 475
• Page End: 488
• Publication Date: 2020-01-24
• Subjects: evolutionary epidemiology -- intra‐strain variation -- plum pox virus -- positive selection -- reversible evolution -- transient attenuation; Plant diseases -- Molecular aspects -- Periodicals; Plant-pathogen relationships -- Molecular aspects -- Periodicals; 571.936
• DOI: 10.1111/mpp.12908
• Languages: English
• ISSNs: 1464-6722

Abstract

Abstract: Plum pox virus (PPV) is one of the most important plant viruses causing serious economic losses. Thus far, strain typing based on the definition of 10 monophyletic strains with partially differentiable biological properties has been the sole approach used for epidemiological characterization of PPV. However, elucidating the genetic determinants underlying intra‐strain biological variation among populations or isolates remains a relevant but unexamined aspect of the epidemiology of the virus. In this study, based on complete nucleotide sequence information of 210 Japanese and 47 non‐Japanese isolates of the PPV‐Dideron (D) strain, we identified five positively selected sites in the PPV‐D genome. Among them, molecular studies showed that amino acid substitutions at position 2, 635 in viral replicase correlate with viral titre and competitiveness at the systemic level, suggesting that amino acid position 2, 635 is involved in aphid transmission efficiency and symptom severity. Estimation of ancestral genome sequences indicated that substitutions at amino acid position 2, 635 were reversible and peculiar to one of two genetically distinct PPV‐D populations in Japan. The reversible amino acid evolution probably contributes to the dissemination of the virus population. This study provides the first genomic insight into the evolutionary epidemiology of PPV based on intra‐strain biological variation ascribed to positive selection. Abstract : This is the first evidence of intra‐strain variation in plum pox virus ascribed to positive selection, especially reversible evolution that contributes to overcoming bottleneck by plant quarantine.