Plant-parasitic nematodes respond to root exudate signals with host-specific gene expression patterns

• Published in: PLoS pathogens Vol. 15; no. 2; p. e1007503
• Main Authors: Bell, Christopher A, Lilley, Catherine J, McCarthy, James, Atkinson, Howard J, Urwin, P E
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01-02-2019; Public Library of Science (PLoS)
• Subjects: Amino acids; Analysis; Animals; Biochemistry; Biological evolution; Biology and Life Sciences; Cell walls; Cellulase - metabolism; Cellulose; Degradation; Endo-1,4-beta Xylanases - metabolism; Endoglucanase; Enzymes; Exudates; Exudation; Flowers & plants; Gene Expression; Gene Expression Profiling - methods; Gene Expression Regulation - genetics; Gene Expression Regulation, Plant - genetics; Genes; Genetic aspects; Genomics; Host-Parasite Interactions - genetics; Invasive species; Legal fees; Medicine and Health Sciences; Nematoda - genetics; Nematoda - metabolism; Nematode Infections - genetics; Nematodes; Pectate lyase; Physical Sciences; Plant Diseases - genetics; Plant Exudates - metabolism; Plant Exudates - physiology; Plant Roots - genetics; Plant Roots - metabolism; Plant tissues; Plant-pathogen relationships; Plants; Polysaccharide-Lyases; Polysaccharides; Research and Analysis Methods; RNA; RNA interference; RNA-mediated interference; Roots (Botany); Roundworms; Substrates; Supervision; Transcription; Up-Regulation; VOCs; Volatile organic compounds; Xylan; United Kingdom > UK; United States > US
• ISSN: 1553-7374; 1553-7366; 1553-7374
• DOI: 10.1371/journal.ppat.1007503

Plant parasitic nematodes must be able to locate and feed from their host in order to survive. Here we show that Pratylenchus coffeae regulates the expression of selected cell-wall degrading enzyme genes relative to the abundance of substrate in root exudates, thereby tailoring gene expression for root entry of the immediate host. The concentration of cellulose or xylan within the exudate determined the level of β-1,4-endoglucanase (Pc-eng-1) and β-1,4-endoxylanase (Pc-xyl) upregulation respectively. Treatment of P. coffeae with cellulose or xylan or with root exudates deficient in cellulose or xylan conferred a specific gene expression response of Pc-eng-1 or Pc-xyl respectively with no effect on expression of another cell wall degrading enzyme gene, a pectate lyase (Pc-pel). RNA interference confirmed the importance of regulating these genes as lowered transcript levels reduced root penetration by the nematode. Gene expression in this plant parasitic nematode is therefore influenced, in a host-specific manner, by cell wall components that are either secreted by the plant or released by degradation of root tissue. Transcriptional plasticity may have evolved as an adaptation for host recognition and increased root invasion by this polyphagous species.