"Flavescence dorée" (FD) is a quarantine disease of Vitis vinifera, associated with phytoplasmas, phloem-limited pathogens in the class Mollicutes. The study of thehost/pathogen interaction is a main topic to which recent research has been directed, in order to clarify the mechanisms of phytoplasma infection, the defense response of the plant, and the biological bases of recovery, an interesting phenomenon of symptom remission that can occur spontaneously in infected plants. Recent proteomic studies conducted on infected grapevines revealed specific protein profile alterations induced by the phytoplasma presence, and bioinformatic analyses identified the most affected metabolic pathways. Among these, the flavonoid pathway has been shown to be specifically modified. The aim of this work was to deeper investigate the changes induced by infection and recovery from FD in this specific pathway, integrating biochemical analysis with gene expression data. Two Italian cultivars, Nebbiolo and Barbera, were selected due to their different sensitivity to phytoplasma infection and recovery occurrence. Samples from leaves of healthy, infected and recovered plants of the two cultivars, were collected at four time-points during the vegetative season. Total flavonoids, anthocyanins and proanthocyanidins were analyzed by spectrophotometry, while flavonol profiles were determined by HPLC. The expression levels of several genes involved in the flavonoid biosynthetic pathway were monitored by quantitative RT-PCR, including upstream genes (CHS), structural genes (F3H, LDOX, UFGT, FLS, LAR, ANR) and transcription factor genes (Myb1A e Myb1F). Variation in mRNA level of the target genes was evaluated and correlated to the plant phonological stage and to the phytosanitary status.
Analisi biochimiche e di espressione genica della via metabolica dei flavonoidi in viti affette da Flavescenza dorata e risanate
Margaria P;Caciagli P;Palmano S
2013
Abstract
"Flavescence dorée" (FD) is a quarantine disease of Vitis vinifera, associated with phytoplasmas, phloem-limited pathogens in the class Mollicutes. The study of thehost/pathogen interaction is a main topic to which recent research has been directed, in order to clarify the mechanisms of phytoplasma infection, the defense response of the plant, and the biological bases of recovery, an interesting phenomenon of symptom remission that can occur spontaneously in infected plants. Recent proteomic studies conducted on infected grapevines revealed specific protein profile alterations induced by the phytoplasma presence, and bioinformatic analyses identified the most affected metabolic pathways. Among these, the flavonoid pathway has been shown to be specifically modified. The aim of this work was to deeper investigate the changes induced by infection and recovery from FD in this specific pathway, integrating biochemical analysis with gene expression data. Two Italian cultivars, Nebbiolo and Barbera, were selected due to their different sensitivity to phytoplasma infection and recovery occurrence. Samples from leaves of healthy, infected and recovered plants of the two cultivars, were collected at four time-points during the vegetative season. Total flavonoids, anthocyanins and proanthocyanidins were analyzed by spectrophotometry, while flavonol profiles were determined by HPLC. The expression levels of several genes involved in the flavonoid biosynthetic pathway were monitored by quantitative RT-PCR, including upstream genes (CHS), structural genes (F3H, LDOX, UFGT, FLS, LAR, ANR) and transcription factor genes (Myb1A e Myb1F). Variation in mRNA level of the target genes was evaluated and correlated to the plant phonological stage and to the phytosanitary status.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
