Characterization of the Pinus massoniana Transcriptional Response to Bursaphelenchus xylophilus Infection Using Suppression Subtractive Hybridization

Abstract

Pine wilt disease (PWD) caused by pine wood nematode (PWN), Bursaphelenchus xylophilus, is the most destructive diseases of pine and poses a threat of serious economic losses worldwide. Although several of the mechanisms involved in disease progression have been discovered, the molecular response of Pinus massoniana to PWN infection has not been explored. We constructed four subtractive suppression hybridization cDNA libraries by taking time-course samples from PWN-inoculated Masson pine trees. One-hundred forty-four significantly differentially expressed sequence tags (ESTs) were identified, and 124 high-quality sequences with transcriptional features were selected for gene ontology (GO) and individual gene analyses. There were marked differences in the types of transcripts, as well as in the timing and levels of transcript expression in the pine trees following PWN inoculation. Genes involved in signal transduction, transcription and translation and secondary metabolism were highly expressed after 24 h and 72 h, while stress response genes were highly expressed only after 72 h. Certain transcripts responding to PWN infection were discriminative; pathogenesis and cell wall-related genes were more abundant, while detoxification or redox process-related genes were less abundant. This study provides new insights into the molecular mechanisms that control the biochemical and physiological responses of pine trees to PWN infection, particularly during the initial stage of infection.

Expression Profiling in Pinus pinaster in Response to Infection with the Pine Wood Nematode Bursaphelenchus xylophilus

“…JRLs proteins have been referenced as a component of the plant defense system, although their role is not well understood yet, due to their structural diversity [66]. In general, the results obtained in the present study are in agreement with the set of candidate genes, related with the response to PWN infection, reported in different studies [20,67]. For instance, the relevance of terpenoid metabolism in maritime pine defense against PWN, important in the resin production process, was pinpointed by Santos and colleagues [20].…”

“…In our work the gene codifying this protein is highly induced immediately after inoculation, decreasing its expression levels slightly over time. The difference observed for the expression pattern of this gene, relative to the study carried by Xu and colleagues [67] in Pinus massoniana, may indicate a specific response for maritime pine.…”

Molecular response of resistant and susceptible apple genotypes to Erwinia amylovora infection

“…Proteins of RD sub-family (Responsive to Dehydratation) are involved in plant defence against abiotic stresses (Gong et al 2005). Xu et al (2013) reported that it was up-regulated in Chinese red pine infected with pine wood nematode Bursaphelenchus xylophilus, but no explanation for its involvement in pathogenesis was provided.…”

Proteomic Analysis Reveals the Positive Roles of the Plant-Growth-Promoting Rhizobacterium NSY50 in the Response of Cucumber Roots to Fusarium oxysporum f. sp. cucumerinum Inoculation

“…The AKRs superfamily comprises a large number of primarily monomeric protein members that reduce a broad spectrum of substrates, which range from simple sugars to potentially toxic aldehydes (Sengupta et al, 2015). There are a number of interesting reports on the active involvement of plant AKRs in detoxification of stress-induced reactive carbonyls as plant defense systems against biotic stress factors, such as pathogenic attack (Tremblay et al, 2010; Santos et al, 2012; Xu et al, 2013). This may be the first report on a type of protein induced by the PGPR that actively contributes to defense against biotic stressors.…”