Plant resistance, which acts as a selective pressure that affects viral population fitness, leads to the emergence of resistance-breaking virus strains. Most recessive resistance to potyviruses is related to the mutation of eukaryotic translation initiation factor 4E (eIF4E) or its isoforms that break their interactions with the viral genome-linked protein (VPg). In this study, we found that the VPg α1-α2 loop, which is essential for binding eIF4E, is the most variable domain of papaya ringspot virus (PRSV) VPg. PRSV VPg with the naturally occurring amino acid substitution of K105Q or E108G in the α1-α2 loop fails to interact with watermelon (Citrullus lanatus) eIF4E but interacts with watermelon eIF(iso)4E instead. Moreover, PRSV carrying these mutations can break the eIF4E-mediated resistance to PRSV in watermelon accession PI 244019. We further revealed that watermelon eIF(iso)4E with the amino acid substitutions of DNQS to GAAA in the cap-binding pocket could not interact with PRSV VPg with natural amino acid substitution of K105Q or E108G. Therefore, our finding provides a precise target for engineering watermelon germplasm resistant to resistance-breaking PRSV isolates.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11588673PMC
http://dx.doi.org/10.1111/mpp.70033DOI Listing

Publication Analysis

Top Keywords

amino acid
16
acid substitution
12
α1-α2 loop
12
prsv vpg
12
naturally occurring
8
occurring amino
8
vpg α1-α2
8
eif4e-mediated resistance
8
resistance prsv
8
substitution k105q
8

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!