Pea (Pisum sativum) is a valuable legume crop recognized for its rich nutritional profile, offering plant-based protein, fiber, vitamins, and essential minerals. It holds a significant place in the growing plant-based protein industry, which is projected to reach $313.5 million by 2025. However, global pea production is declining due to soilborne diseases, notably root rots caused by Fusarium solani f. sp. pisi (Fsp). In our earlier study, we performed time-course transcriptome analysis on four Fsp-tolerant and four Fsp-susceptible pea genotypes during pathogen infection, identifying several Fsp-responsive genes. Interestingly, the dataset also contained Fusarium-derived genes, many of which encode ubiquitin, ubiquitin-like proteins, and the ubiquitin-40S ribosomal protein S31 fusion protein. EffectorP analysis revealed that these proteins are secretory in nature. We hypothesize that Fusarium secretes these proteins into host cells to manipulate the host’s ubiquitin-proteasome system, leading to the degradation of plant defense proteins. To explore this further, we investigated RING-type E3 ligase proteins in Pisum sativum, which play key roles in protein ubiquitination. A total of 663 genes encoding RING-type E3 ligases were identified, each containing at least one RING domain as predicted by the SMART database. Domain analysis revealed additional conserved motifs within these proteins. An Un-rooted Neighbor-Joining phylogenetic tree grouped the RING proteins based on shared domain architecture. Transcriptomic data indicates that these genes are differentially expressed during Fsp infection. The E3 Ligase genes are upregulated in Fsp-susceptible cultivars and downregulated in Fsp-tolerant cultivars. These genes can be used to generate future knock-out mutants and perform functional studies to enhance pea resistance to Fsp-induced root rot.
