Abstract:
Root-knot nematode (RKN) Meloidogyne javanica presents a great challenge to Solanaceae
crops, including potato. In this study, we investigated transcriptional responses of potato roots
during a compatible interaction with M. javanica. In this respect, differential gene expression
of Solanum tuberosum cultivar (cv.) Mondial challenged with M. javanica at 0, 3 and 7 days
post-inoculation (dpi) was profiled. In total, 4948 and 4484 genes were detected, respectively,
as differentially expressed genes (DEGs) at 3 and 7 dpi. Functional annotation revealed that genes
associated with metabolic processes were enriched, suggesting they might have an important
role in M. javanica disease development. MapMan analysis revealed down-regulation of genes
associated with pathogen perception and signaling suggesting interference with plant immunity
system. Notably, delayed activation of pathogenesis-related genes, down-regulation of disease
resistance genes, and activation of host antioxidant system contributed to a susceptible response.
Nematode infestation suppressed ethylene (ET) and jasmonic acid (JA) signaling pathway hindering
JA/ET responsive genes associated with defense. Genes related to cell wall modification were
differentially regulated while transport-related genes were up-regulated, facilitating the formation
of nematode feeding sites (NFSs). Several families of transcription factors (TFs) were differentially
regulated by M. javanica infestation. Suggesting that TFs play an indispensable role in physiological
adaptation for successful M. javanica disease development. This genome-wide analysis reveals the
molecular regulatory networks in potato roots which are potentially manipulated by M. javanica.
Being the first study analyzing transcriptome profiling of M. javanica-diseased potato, it provides
unparalleled insight into the mechanism underlying disease development.
