Signaling Pathways and Downstream Effectors of Host Innate Immunity in Plants

Abstract

Phytopathogens, such as biotrophs, hemibiotrophs and necrotrophs, pose serious stress on the development of their host plants, compromising their yields. Plants are in constant interaction with such phytopathogens and hence are vulnerable to their attack. In order to counter these attacks, plants need to develop immunity against them. Consequently, plants have developed strategies of recognizing and countering pathogenesis through pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). Pathogen perception and surveillance is mediated through receptor proteins that trigger signal transduction, initiated in the cytoplasm or at the plasma membrane (PM) surfaces. Plant hosts possess microbe-associated molecular patterns (P/MAMPs), which trigger a complex set of mechanisms through the pattern recognition receptors (PRRs) and resistance (R) genes. These interactions lead to the stimulation of cytoplasmic kinases by many phosphorylating proteins that may also be transcription factors. Furthermore, phytohormones, such as salicylic acid, jasmonic acid and ethylene, are also effective in triggering defense responses. Closure of stomata, limiting the transfer of nutrients through apoplast and symplastic movements, production of antimicrobial compounds, programmed cell death (PCD) are some of the primary defense-related mechanisms. The current article highlights the molecular processes involved in plant innate immunity (PII) and discusses the most recent and plausible scientific interventions that could be useful in augmenting PII.

A Pathogen-Inducible Rice NAC Transcription Factor ONAC096 Contributes to Immunity Against Magnaprothe oryzae and Xanthomonas oryzae pv. oryzae by Direct Binding to the Promoters of OsRap2.6, OsWRKY62, and OsPAL1

“…Disease assays revealed that loss-of function of ONAC096 in ONAC096-CP and onac096 plants exhibited decreased while overexpression of ONAC096 strengthened resistance to M. oryzae and Xoo (Figures 3, 4 and Supplementary Figure 4). PTI is the first layer of immune response in plants, which can be triggered via activation of PRRs by chitin, flagellin or other elicitor, accompanying a set of signaling cascades including ROS burst and induction of PTI-related defense genes (Wang et al, 2019;Kumar et al, 2021;Yuan et al, 2019b;Yuan X. et al, 2021). Overexpression of ONAC096 triggered while knockout of ONAC096 suppressed chitin-or flg22-induced ROS burst and PTI marker gene expression (Figure 5).…”

“…To defend themselves against potential pathogens, plants have evolved a complicated and fine-tuned innate immune system, which consists of pattern-triggered immunity (PTI) and effectortriggered immunity (ETI) (Jones and Dangl, 2006;Boller and He, 2009;Zhou and Zhang, 2020). PTI is the first layer of immune response that is initiated upon perception of conserved PAMP/MAMP/DAMP by cell surfacelocalized pattern recognition receptors (PRRs) (Boller and Felix, 2009;Kumar et al, 2021). ETI is the second layer of immune response that is stimulated upon direct or indirect recognition of pathogen-secreted effectors by intracellular resistance proteins (Jones and Dangl, 2006;Zhou and Zhang, 2020).…”

The effectivity of banana leaf-filtered cloth face masks as an alternative protection during the pandemic

“…Therefore, the ideal banana leaf that is inserted is from the banana plant, which does not bear the fruits. The wounds or the damage on the leaf surface caused by insects or environmental, mechanical damage, such as rain and wind, can be the potential routes of bacteria to enter the leaves in addition to the natural openings [32]. Therefore, selecting the whole, undamaged leaves as filters on the cloth face masks is highly recommended.…”

Research Progress of ATGs Involved in Plant Immunity and NPR1 Metabolism

“…Based on the N-terminal structures, NLR proteins can be classified into two categories. TIR-NLR (TNLs) contain the toll/interlcukin-1-reccptor (TIR) region and CC-NLR (CNLs) contain coiled coil (CC) domain [9][10][11][12][13][14][15].…”