MicroRNAs, New Players in the Plant–Nematode Interaction

Abstract

Plant-parasitic root-knot and cyst nematodes are microscopic worms that cause severe damage to crops and induce major agricultural losses worldwide. These parasites penetrate into host roots and induce the formation of specialized feeding structures, which supply the resources required for nematode development. Root-knot nematodes induce the redifferentiation of five to seven root cells into giant multinucleate feeding cells, whereas cyst nematodes induce the formation of a multinucleate syncytium by targeting a single root cell. Transcriptomic analyses have shown that the induction of these feeding cells by nematodes involves an extensive reprogramming of gene expression within the targeted root cells. MicroRNAs are small noncoding RNAs that act as key regulators of gene expression in eukaryotes by inducing the posttranscriptional silencing of protein coding genes, including many genes encoding transcription factors. A number of microRNAs (miRNAs) displaying changes in expression in root cells in response to nematode infection have recently been identified in various plant species. Modules consisting of miRNAs and the transcription factors they target were recently shown to be required for correct feeding site formation. Examples include miR396 and GRF in soybean syncytia and miR159 and MYB33 in Arabidopsis giant cells. Moreover, some conserved miRNA/target modules seem to have similar functions in feeding site formation in different plant species. These miRNAs may be master regulators of the reprogramming of expression occurring during feeding site formation. This review summarizes current knowledge about the role of these plant miRNAs in plant–nematode interactions.

Potassium Deficiency Significantly Affected Plant Growth and Development as Well as microRNA-Mediated Mechanism in Wheat (Triticum aestivum L.)

“…MicroRNAs (miRNAs) are small regulatory RNA molecules that bind to target mRNA sequences and form a mRNA-induced gene silencing complex (RISC) (Li and Zhang, 2016). They are a class of small non-coding RNAs responsible for regulating target genes in many metabolic and developmental processes (Li and Zhang, 2016;Jaubert-Possamai et al, 2019). miRNAs are approximately 20-22 nucleotides in length and are processed by Dicer-like 1 (DCL1) enzyme from precursor sequences (pre-miRNAs) in plants.…”

“…miRNAs are approximately 20-22 nucleotides in length and are processed by Dicer-like 1 (DCL1) enzyme from precursor sequences (pre-miRNAs) in plants. miRNAs are highly evolutionarily conserved from species to species (Zhang et al, 2006); many miRNAs are involved in the regulation of plant response to abiotic and biotic stresses (Zhang, 2015;Jaubert-Possamai et al, 2019). Gene expression is inhibited by miRNAs in two ways: either by the targeted degradation of mRNA molecules or by inhibition of protein translation.…”

Identification of MicroRNAs That Respond to Soybean Cyst Nematode Infection in Early Stages in Resistant and Susceptible Soybean Cultivars

“…To date, the function of miR159, miR172, and miR319 in the interaction between plants and plant parasitic nematodes are the few miRNA functions that have been deeply elucidated [22,55,56], and many questions remain surrounding the roles of miRNAs in plant parasitism by nematodes. For instance, cross-kingdom RNA silencing probably also occurs during interactions between plants and plant parasitic nematodes [57]. In other plant species, recent studied have indicated that plant miRNAs can silence the transcripts of plant pathogens that are important for virulence [21], and that miRNAs from the plant pathogen also can silence genes of their hosts that are important for immunity [58].…”

Gall-Inducing Parasites: Convergent and Conserved Strategies of Plant Manipulation by Insects and Nematodes

“…Although it is difficult to make direct comparisons between differentially expressed genes in these interactions due to the absence of common hosts, the assignment of these genes to functional categories has highlighted the importance of modifications to plant defense responses (55,105), hormone pathways (50), the cell cycle (32), the cell wall and cytoskeleton organization (15,47,78), developmental processes (122), and metabolic reprogramming (111,121). The regulation of host gene expression by transcription factors, small noncoding RNAs and epigenetics remains poorly documented despite its importance (70). Here, we highlight the similarities between these plant reprogrammers in terms of the suppression of plant defenses, the manipulation of hormone balance, and changes to cell wall architecture at feeding sites.…”