Signal Transduction in Plant–Nematode Interactions

Abstract

To successfully invade and infect their host plants, plant parasitic nematodes (PPNs) need to evolve molecular mechanisms to overcome the defense responses from the plants. Nematode-associated molecular patterns (NAMPs), including ascarosides and certain proteins, while instrumental in enabling the infection, can be perceived by the host plants, which then initiate a signaling cascade leading to the induction of basal defense responses. To combat host resistance, some nematodes can inject effectors into the cells of susceptible hosts to reprogram the basal resistance signaling and also modulate the hosts’ gene expression patterns to facilitate the establishment of nematode feeding sites (NFSs). In this review, we summarized all the known signaling pathways involved in plant–nematode interactions. Specifically, we placed particular focus on the effector proteins from PPNs that mimic the signaling of the defense responses in host plants. Furthermore, we gave an updated overview of the regulation by PPNs of different host defense pathways such as salicylic acid (SA)/jasmonic acid (JA), auxin, and cytokinin and reactive oxygen species (ROS) signaling to facilitate their parasitic successes in plants. This review will enhance the understanding of the molecular signaling pathways involved in both compatible and incompatible plant–nematode interactions.

Piriformospora indica promotes cucumber tolerance against Root-knot nematode by modulating photosynthesis and innate responsive genes

“…However, biotic stress defense hormones are considered a part of complex network of synergistic and antagonistic interactions (Fraire-Velázquez et al, 2011). Salicylic is a key player in the stimulation of dissimilar signing paths in resistance feed back in plants, when they encounter nematode infections (Ali et al, 2018). It improves the host immune response, compromises the plant defense system whereas and reported to enhance a set of pathogenesis-related defense genes against the phytoparasitic nematode in tomato (Branch et al, 2004) and the suppression of host resistance SA was connected with the development of nematode in tomato (De Medeiros et al, 2017).…”

Biological Control of Plant-Parasitic Nematodes by Filamentous Fungi Inducers of Resistance: Trichoderma, Mycorrhizal and Endophytic Fungi

“…Once the attack occurred, the plants recognize non-specific molecules of the cell wall of the microorganisms [pathogen-and/or Microbial-Associated Molecular Patterns (PAMPs/MAMPs)], the oral secretions of the herbivores [herbivore-associated molecular patterns (HAMPs)] or signs of cell-plant damage [Damage-Associated Molecular Patterns (DAMPs)], by cell surface pattern recognition receptors (PRRs) (Mithöfer and Boland, 2008;Ramírez-Prado et al, 2018;Hou et al, 2019). Nematode-Associated Molecular Patterns (NAMPs) and its associated receptors have been scarcely described (reviewed in Ali et al, 2018). However, it is generally accepted that during the plant-pathogen interactions, the detection of PAMPs and DAMPs by PRRs triggers a complex network of intracellular signaling cascades leading to defense responses known as PAMP-triggered immunity (PTI).…”

Transfer cells: what regulates the development of their intricate wall labyrinths?

“…Invading nematodes dampen host ROS defence responses by secreting superoxide dismutases (SODs) and other ROS scavenging enzymes (Ali et al ., 2018) that may create a ROS profile to drive WL development in their feeding sites. For example, nematode‐induced expression of host respiratory burst oxidases (Rbohs) acts antagonistically to suppress the salicylic acid host defence response with the result of nurturing nematode feeding site development (Siddique et al ., 2014).…”