Comparative proteomics of three Chinese potato cultivars to improve understanding of potato molecular response to late blight disease

Abstract

Background Late blight disease (LBD) caused by the pathogen Phytophthora infestans (PI), is the most devastating disease limiting potato (Solanum tuberosum) production globally. Currently, this disease pathogen is re-emerging and appearing in new areas at a very high intensity. A better understanding of the natural defense mechanisms against PI in different potato cultivars especially at the protein level is still lacking. Therefore, to elucidate potato proteome response to PI, we investigated changes in the proteome and leaf morphology of three potato cultivars, namely; Favorita (FA), Mira (MA), and E-malingshu N0.14 (E14) infected with PI by using the iTRAQ-based quantitative proteomics analysis. Results A total of 3306 proteins were found in the three potato genotypes, and 2044 proteins were quantified. Cluster analysis revealed MA and E14 clustered together separately from FA. The protein profile and related functions revealed that the cultivars shared a typical hypersensitive response to PI, including induction of elicitors, oxidative burst, and suppression of photosynthesis in the potato leaves. Meanwhile, MA and E14 deployed additional specific response mechanism different from FA, involving high induction of protease inhibitors, serine/threonine kinases, terpenoid, hormone signaling, and transport, which contributed to MA tolerance of LBD. Furthermore, inductions of pathogenesis-related proteins, LRR receptor-like kinases, mitogen-activated protein kinase, WRKY transcription factors, jasmonic acid, and phenolic compounds mediate E14 resistance against LBD. These proteins were confirmed at the transcription level by a quantitative polymerase chain reaction and at the translation level by western-blot. Conclusions We found several proteins that were differentially abundant among the cultivars, that includes common and cultivar specific proteins which highlighted similarities and significant differences between FA, MA, and E14 in terms of their defense response to PI. Here the specific accumulation of mitogen-activated protein kinase, Serine/threonine kinases, WRKY transcription played a positive role in E14 immunity against PI. The candidate proteins identified reported in this study will form the basis of future studies and may improve our understanding of the molecular mechanisms of late blight disease resistance in potato.

Transcriptional alterations of the resistant potato genotype ‘Cruza 148’ in response to Ralstonia solanacearum infection

“…However, this is in contrast with a study by Xiao et al. (2020) where three potato genotypes infected with Phytophthora infestans exhibited upregulation of ‘protein processing reticulum’. The ‘Shangi’ genotype exhibited no differentially expressed genes in ‘defence response’ at any time point in an enriched GO term.…”

“…Downregulation of protein processing reticulum during disease development may redirect resources towards defence responses and disrupt normal ER functions, potentially due to pathogen presence or immune responses disrupting ER functions,which is common during pathogen-host interactions. However, this is in contrast with a study byXiao et al (2020) where three potato genotypes infected with Phytophthora infestans exhibited upregulation of 'protein processing reticulum'. The 'Shangi' genotype exhibited no differentially expressed genes in 'defence response' at any time point in an enriched GO term.…”

Comparative transcriptome profiling of potato cultivars infected by late blight pathogen Phytophthora infestans: Diversity of quantitative and qualitative responses

“…In response to P. infestans infection in Ando, a shift from photosynthesis to promoting an immune response is likely possible. Photosynthetic inhibition has also been observed in previous research on the response of potato to P. infestans infection [ 52 , 137 , 149 ]. The study also reveals that the SA-JA-ET pathways are also involved in defense response at 72 hpi which corresponds to the necrotrophic stage of infection in support of some other researchers [ 143 ].…”

“…In this case, the plant places a higher priority on building a robust defense response in preference to growth [ 120 ]. This noticeable shift in priority from photosynthesis to defense response has been reported [ 27 , 34 , 52 , 94 , 121 , 137 , 139 , 149 ].…”

Secondary Metabolites, Other Prospective Substances, and Alternative Approaches That Could Promote Resistance against Phytophthora infestans

“…Different proteomics studies targeting leaves, tubers, and secreted proteins in the apoplast have extended the list of putative resistance markers. These studies have identified the expected targets (R proteins, osmotins, peroxidases, protease inhibitors, and lipid transfer proteins), as well as transcription factors and multiple defense-related proteins, including glutathione S-transferases, endochitinase, glycosyltransferase, glucosidases, and heat shock proteins 70 [138,194,[196][197][198][199][200][201][202][203][204]. However, most of these candidates for MAS need to be validated in dedicated mechanistic studies.…”