Phytoplasmas are plant pathogenic bacteria transmitted by hemipteran phloem sucking insects in a persistent, propagative manner. Recent studies on 'Candidatus Phytoplasma asteris' showed that the major antigenic membrane protein (Amp) specifically interacts with vector proteins, with both cytosolic (actin and myosin) and membrane (ATP synthase) localization. The gut epithelium and salivary glands are physical barriers that must be overcome by the phytoplasma during vector colonization. Specific interactions of Amp with vector membrane proteins occur in vitro at both sites. Aim of this work was to develop a system to study the effects of phytoplasma membrane proteins on vector acquisition and transmission capabilities. To investigate the effects of the interactions of the chrysanthemum yellows phytoplasma (CYP) Amp at the gut epithelium, vectors of two species (Macrosteles quadripunctulatus Kirschbaum, and Euscelidius variegatus Kirschbaum), before acquisition on CYP infected plants, were fed on a medium containing i) a fusion construct of the protein, ii) a fusion protein of ArtI, a membrane protein not involved in specific interaction with vectors, iii and iv) antibodies raised against Amp and ArtI, v) no proteins. To investigate the effects of the interactions at the salivary gland level, fusion Amp and its specific antibody were added to a suspension of CYP and microinjected in the abdomen of E. variegatus. After latency, insects from both sets of experiments were singly caged on healthy plants for the inoculation, collected and assayed in PCR for the presence of CYP. Phytoplasma titre in insects was also quantified by RT-PCR. The results showed a role of CYP Amp in the transmission process by vector insects.
In vivo assays to test the role of phytoplasma membrane proteins on vector acquisition and transmission capabilities
Rashidi M;Galetto L;Veratti F;Bosco D;
2013
Abstract
Phytoplasmas are plant pathogenic bacteria transmitted by hemipteran phloem sucking insects in a persistent, propagative manner. Recent studies on 'Candidatus Phytoplasma asteris' showed that the major antigenic membrane protein (Amp) specifically interacts with vector proteins, with both cytosolic (actin and myosin) and membrane (ATP synthase) localization. The gut epithelium and salivary glands are physical barriers that must be overcome by the phytoplasma during vector colonization. Specific interactions of Amp with vector membrane proteins occur in vitro at both sites. Aim of this work was to develop a system to study the effects of phytoplasma membrane proteins on vector acquisition and transmission capabilities. To investigate the effects of the interactions of the chrysanthemum yellows phytoplasma (CYP) Amp at the gut epithelium, vectors of two species (Macrosteles quadripunctulatus Kirschbaum, and Euscelidius variegatus Kirschbaum), before acquisition on CYP infected plants, were fed on a medium containing i) a fusion construct of the protein, ii) a fusion protein of ArtI, a membrane protein not involved in specific interaction with vectors, iii and iv) antibodies raised against Amp and ArtI, v) no proteins. To investigate the effects of the interactions at the salivary gland level, fusion Amp and its specific antibody were added to a suspension of CYP and microinjected in the abdomen of E. variegatus. After latency, insects from both sets of experiments were singly caged on healthy plants for the inoculation, collected and assayed in PCR for the presence of CYP. Phytoplasma titre in insects was also quantified by RT-PCR. The results showed a role of CYP Amp in the transmission process by vector insects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
