Project description:The worldwide pest grape phylloxera (Daktulosphaira vitifoliae Fitch) is threatening vititulure. We investigated the compatible interaction with the host Teleki 5C (Vitis berlandiere Planch. X V. riparia Michx.) by investigating differential gene expression analysis using a custom made microarray. Samples (root tips and nodosities) were obtained from not infected and infected one-node cuttings four weeks after inoculation with 60 sibling phylloxera eggs. Four independent biological replicates each were analysed using a doul-color microarray experiment. Dye-swap hybridizations were performed. In total eight microarray were used for hybridization.
Project description:Herbivory plant-parasite interactions depend on the delivery of effector molecules by the invading insect species. Sedentary gall forming insects, such as grape phylloxera (Daktulosphaira vitifoliae FITCH, Phylloxeridae) secrete multiple effectors into host plant tissues that alter host cellular functions to the benefit of the insect. Analyses revealed 420 putative ‘DvEffectors’ were detected in salivary glands, dissected from root-feeding vs. starving D. vitifoliae larvae reared on Teleki 5C (V. berlandieri x V. riparia) under controlled growth conditions (25±3°C, 60% rH) by proteomic mass spectrometry and in-silico secretory prediction. Sixty-two conserved DvEffectors were shared with the aphid species A. pisum, M. persicae and R. padi including candidate effector proteins involved in feeding site establishment, plant defence suppression and nutrient uptake
Project description:Some insects can redirect plant development to form unique organs called galls, which provide these insects with unique, enhanced food and protection from enemies and the elements. Many galls resemble flowers or fruits, suggesting that elements of reproductive development may be involved. We addressed this possibility using RNA sequencing (RNAseq) to quantify the transcriptional responses of wild grapevine (Vitis riparia Michx.) leaves to a galling parasite, phylloxera (Daktulosphaira vitifoliae (Fitch 1855)). If development of reproductive structures is part of gall formation, we expected to find significantly elevated expression of genes involved in flower and/or fruit development in developing galls as opposed to ungalled leaves. We found that reproductive gene ontology classes were significantly enriched in developing galls, and that expression of many putative genes involved in flower formation was significantly increased, particularly in later gall stages. The patterns of gene expression found in galls suggest that phylloxera exploits vascular cambium to provide meristematic tissue and redirects leaf development towards formation of carpels. The phylloxera leaf gall, and perhaps other similar galls, appears to be phenotypically and transcriptionally convergent on the plant carpel.