Llular level. Up-regulated resistance proteins are represented with yellow stars and important steps of the

Llular level. Up-regulated resistance proteins are represented with yellow stars and important steps of the reactions in red. Up-regulated DEGs are in blue. Enzymes involved in the defense response are in orangeactivating plant defense responses [35]. Strictosidine synthase-like proteins have also been identified during plant defense activated against pathogens such as the Cucumber mosaic virus and Alternaria brassicicola [36]. The cellular damage induced by the necrotrophic pathogen could also lead to water loss [37], and the activation of a dehydrin (Solyc12g099390.1.1) and a glutamine synthetase (Solyc04g014510.2.1) in the resistant genotype could help to redress the osmotic stress, avoiding FORL-induced root and crown rot [4] evidenced a high level accumulation of dehydrin proteins in Momor plants infected by FORL, as well as larger amounts of glutamine synthetase (EC: 6.3.1.2; Solyc04g014510.2.1), an enzyme involved in the nitrogen assimilation pathway, supporting our results. Glutamine synthetase could alter glutamate metabolism, resulting in an “endurance” state as already reported in other necrotrophic pathogen interactions [38]. Endurance can be defined as a state in whichFig. 7 Compatible interaction model. Graphical representation of Monalbo-FORL interaction at cellular level. Down-regulated LRR resistance protein is represented with yellow stars “blocked” by a red cross and the major steps of the reactions are in red. Up-regulated DEGs are in blueManzo et al. BMC Plant Biology (2016) 16:Page 12 ofcell viability is maintained via nitrogen (N) reutilization and involved in a senescence-natured `slash-and-burn’ defense response [39]. Translocation of N toward the invaded area proved to be effective for a resisting host [40, 41]. The upregulation of a glutathione S-transferase (GST), together PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/27362935 with the increased protein levels found in the MomorFORL interaction [4], supports its involvement in the resistance process. Since the Momor genotype constitutively showed higher amounts of glutathione S-transferase regardless of FORL infection, it could be inferred that this protein is involved in the resistance process [4]. It is well known that GST contributes to mitigate further oxidative damage in cells surrounding the infected areas [20, 42, 43]. In the compatible interaction an up-regulated Jasmonate ZIM-domain protein and an up-regulated Omega-6 fatty acid desaturase were detected. Generally, JA and ET play an important role in defense responses to necrotrophic pathogens and chewing insects, while SA is more involved in responses to biotrophs and sucking insects [44, 45]. Investigation of the tomato-FORL interaction at proteomic level confirms the presence of higher amounts of peroxidases in the compatible interaction [4]. An unspecific monooxygenase could also be involved in oxidoreductase activity and in necrosis in the susceptible variety in response to a pathogen. GO terms correlated with the metabolic process and response to stress, including several genes coding for PR-proteins like Beta1,3-glucanase, chitinases and protease inhibitor, were up-regulated in the comparison between the two inoculated genotypes. PRproteins accumulate locally in the infected and surrounding tissues and also in remote uninfected tissues [46]. Among these proteins Beta1, 3-glucanases and chitinases are very abundant buy U0126 hydrolytic enzymes in plants infected by fungi and play a major role in defense reactions against fungal pathogens by degrading the cel.