AUTHOR=Li Huangai , Kondo Hideki , Kühne Thomas , Shirako Yukio 

TITLE=Barley Yellow Mosaic Virus VPg Is the Determinant Protein for Breaking eIF4E-Mediated Recessive Resistance in Barley Plants

JOURNAL=Frontiers in Plant Science

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2016.01449

DOI=10.3389/fpls.2016.01449

ISSN=1664-462X

ABSTRACT=<p>In this study, we investigated the barley yellow mosaic virus (BaYMV, genus <italic>Bymovirus</italic>) factor(s) responsible for breaking eIF4E-mediated recessive resistance genes (<italic>rym4</italic>/<italic>5</italic>/<italic>6</italic>) in barley. Genome mapping analysis using chimeric infectious cDNA clones between <italic>rym5</italic>-breaking (JT10) and <italic>rym5</italic>-non-breaking (JK05) isolates indicated that genome-linked viral protein (VPg) is the determinant protein for breaking the <italic>rym5</italic> resistance. Likewise, VPg is also responsible for overcoming the resistances of <italic>rym4</italic> and <italic>rym6</italic> alleles. Mutational analysis identified that amino acids Ser-118, Thr-120, and His-142 in JT10 VPg are the most critical residues for overcoming <italic>rym5</italic> resistance in protoplasts. Moreover, the <italic>rym5</italic>-non-breaking JK05 could accumulate in the <italic>rym5</italic> protoplasts when eIF4E derived from a susceptible barley cultivar was expressed from the viral genome. Thus, the compatibility between VPg and host eIF4E determines the ability of BaYMV to infect barley plants.</p>