Transcriptomic Analysis of Nematode Infestation

Abstract

The establishment and maintenance of nematode feeding sites and subsequent nematode development are associated with significant changes in expression level of both plant and nematode genes. Analysis of the changes in transcript abundance during feeding site establishment and function provides insight into the complexity of plant-nematode interactions and may lead to the discovery of novel strategies for managing nematodes. Early techniques of gene discovery had identified a small cadre of genes induced in the plant host or invading nematode. More recently, the adoption of high-throughput gene expression tools such as microarrays has allowed the identification of hundreds of both plant and nematode genes that are regulated over the course of nematode infestation. Initially, microarray studies were used to examine gene expression in whole infested roots or nematode feeding site-enriched tissues. More recently, the combination of laser-assisted microdissection of nematode feeding sites and subsequent transcriptomic analyses using microarrays has provided an unprecedented view of gene expression within the feeding site itself. This chapter is intended to present a broad overview of the knowledge gained to date about techniques that have been used to identify differentially regulated genes of both plant and nematode during the plant-nematode interaction and recent methodological improvements crucial for future studies.

Molecular Insights in the Susceptible Plant Response to Nematode Infection

“…GC, giant-cell; N, nematode; Syn, syncytium; NOS, nopaline synthase. Bars -100 µm 2004 ; Wang et al 2003) have significantly enlarged the list of nematoderesponsive genes (Li et al 2008) and confirmed previous analyses that the down-regulation of genes is as relevant to NFS formation as gene induction (Gheysen and Fenoll 2002) . In the following sections, we highlight recent molecular insights into the susceptible plant response to nematode infection, particularly with regard to the plant genes involved, and how these genes may be contributing to the induction and function of NFS.…”

“…More recent microarray analyses in Arabidopsis and soybean (Jammes et al 2005 ;Puthoff et al 2003 ;Ithal et al 2007a ,b) have identified the differential regulation of several additional classes of CWMPs, including xyloglucan endotransglycosylases (XETs), b-xylosidases, reversibly glycosylated polypeptides (RGPs), and pectate lyases (see Li et al 2008). From these studies it is evident that feeding cell formation is a complex process that likely requires the synergistic activity and coordinated regulation of several different types of plant CWMPs, as well as the differential expression of individual gene family members.…”

Transcriptional reprogramming by root knot and migratory nematode infection in rice

“…Plants generally respond to nematode infection by differential expression of genes involved in stress and defense responses, cell wall alteration, metabolism and nutrient allocation, signal transduction and phytohormone action (Li et al ., ; Escobar et al ., ). In accordance with these previous observations, genes involved in those categories were differentially expressed in the current study.…”

Comparing systemic defence‐related gene expression changes upon migratory and sedentary nematode attack in rice

“…Plants generally respond to sedentary nematode infection by differential expression of genes involved in stress and defence responses, cell wall alteration, metabolism and nutrient allocation and signal transduction for phytohormone action (Li et al. 2008).…”