Proteomics of PTI and Two ETI Immune Reactions in Potato Leaves

Abstract

Plants have a variety of ways to defend themselves against pathogens. A commonly used model of the plant immune system is divided into a general response triggered by pathogen-associated molecular patterns (PAMPs), and a specific response triggered by effectors. The first type of response is known as PAMP triggered immunity (PTI), and the second is known as effector-triggered immunity (ETI). To obtain better insight into changes of protein abundance in immunity reactions, we performed a comparative proteomic analysis of a PTI and two different ETI models (relating to Phytophthora infestans) in potato. Several proteins showed higher abundance in all immune reactions, such as a protein annotated as sterol carrier protein 2 that could be interesting since Phytophthora species are sterol auxotrophs. RNA binding proteins also showed altered abundance in the different immune reactions. Furthermore, we identified some PTI-specific changes of protein abundance, such as for example, a glyoxysomal fatty acid beta-oxidation multifunctional protein and a MAR-binding protein. Interestingly, a lysine histone demethylase was decreased in PTI, and that prompted us to also analyze protein methylation in our datasets. The proteins upregulated explicitly in ETI included several catalases. Few proteins were regulated in only one of the ETI interactions. For example, histones were only downregulated in the ETI-Avr2 interaction, and a putative multiprotein bridging factor was only upregulated in the ETI-IpiO interaction. One example of a methylated protein that increased in the ETI interactions was a serine hydroxymethyltransferase.

Grapevine – Downy Mildew <em>Rendez-Vous</em>: Proteome Analysis of the First Hours of an Incompatible Interaction

“…It has been described that A. thaliana plants with a shmt1-1 mutation are more susceptible to biotrophic and necrotrophic pathogens in relation to control plants [40]. This protein has also been found to increase in effector-triggered immunity (ETI) interactions [41], which is in agreement with the observed data in this study. V. vinifera 'Regent' is a tolerant plant to P. viticola pathogen and at 12 hpi an ETI response might be taking place in response to pathogen effectors.…”

Comprehensive Time-Series Analysis of the Gene Expression Profile in a Susceptible Cultivar of Tree Tomato (Solanum betaceum) During the Infection of Phytophthora betacei

“…Even though we observed the expression of pathways involved in HR as mentioned above, we can presume that oomycete effectors are capable of suppressing the host immunity resulting in ETS ( Resjö et al, 2019 ). Also, we observed expression of resistance genes, such as putative late blight resistance protein homolog R1A-10 that recognizes Avr1 of P. infestans , but it is reasonable to consider that the effectors proteins are not being recognized by these R -genes or the gene-for-gene interaction is blocked by other effector proteins ( Halterman et al, 2010 ; Yang et al, 2018 ) because the infection successfully progressed until necrotrophy.…”

Volatile Compounds From Bacillus, Serratia, and Pseudomonas Promote Growth and Alter the Transcriptional Landscape of Solanum tuberosum in a Passively Ventilated Growth System

“…The protein (EDS1) has been shown, in association with salicylic acid (SA), to mediate redundant functions in R protein-mediated defense signaling confirmed by simultaneous mutations of EDS1 and a salicylic acid-synthesizing enzyme named SID2 resulting in a compromised defense and/or hypersensitive response mediated by R proteins which contain a coiledcoil domain residing in their N-terminal domains (Venugopal et al, 2009). A membrane protein involved in cell wall strengthening, UPF0497, was shown to be upregulated in the PTI response to Phytophthora infestans (Resjö et al, 2019), this class of membrane protein was also downregulated in our study. The fact that there are only three BVCs shared in common between LAC2 and FZB24 suggests that these BVCs may be responsible for the induction of the five commonly downregulated DEGs between these isolates and is worthy of future investigation.…”