Functional analysis of aphid resistance genes RlWRKY10 and RlWRKY14

Abstract

WRKY transcription factors are crucial for plant growth, development, and resistance to abiotic stress. Based on previous work in our laboratory, we identified members of the Rosa longicuspis WRKY family and performed bioinformatic analyses on the 27 identified members to explore the biological function of the WRKY gene in Rosa longicuspis against aphids. The 27 members' chromosomal locations and intraspecies collinearity analysis revealed that they were unequally distributed on 7 chromosomes, with 7 pairs of genes having collinearity. Homologous evolution analysis was performed on the 27 members identified in Rosa longicuspis and the 44 WRKY genes of Fragaria vesca, and 6 stress resistance candidate genes of Rosa longicuspis were screened from the resistance clades. Further qPCR experiments on the six selected stress resistance candidate genes revealed that two of them (RlWRKY10 and RlWRKY14) were significantly upregulated after being stressed by Macrosiphum rosae, approximately 5 times that of the control group. Then, the two target genes identified by qPCR were silenced using VIGS technology. The plants exhibited severe leaf shrinkage and increased aphid production after gene silencing, indicating that these two genes interacted in the host and Macrosiphum rosae and play an important role in the stress resistance process. The overexpression vectors of the two target genes were constructed by homologous recombination technology, which were then transferred into Arabidopsis thaliana. The results showed that the aphid resistance of the transgenic plants was significantly higher than that of the control group. In conclusion, the RlWRKY10 and RlWRKY14 genes play positive regulatory roles in the host's interaction with Macrosiphum rosae.