ATTARD , Agnès

ABSTRACT The cyst of the protist ciliate Vorticella efficiently differentiates into teletroch, the free-swimming stage. Here, using video microscopy and quantitative imaging we establish that the cyst differentiation follows two strict temporal and spatial patterns. The temporal pattern is initially marked by the functional formation of the...

To explore moist soils and to target host plants, phytopathogenic Phytophthora species utilize the sensory and propulsion capabilities of the biflagellate unicellular zoospores they produce. Zoospore motion and interactions with the microenvironment are of primary importance for Phytophthora physiology. These are also of critical significance...

Biotrophic filamentous plant pathogens frequently establish intimate contact with host cells through intracellular feeding structures called haustoria. To form and maintain these structures, pathogens must avoid or suppress defence responses and reprogramme the host cell. We used Arabidopsis whole-genome microarrays to characterize genetic...

International audience

The root tip and root-Associated Cap-Derived Cells (AC-DCs) release various organic compounds into the rhizosphere, forming the Root Extracellular Trap (RET), a network involved in root-soil microorganism interactions and root protection. This study investigates the role of soybean (Glycine max) and pea (Pisum sativum) RETs in interactions with...

Abstract Background Microorganisms evolved complex systems to respond to environmental signals. Gradients of particular molecules alter microbe behavior and distribution within their environment. Microdevice tools coupled to automated image-based methods are now employed to analyze instantaneous distribution and motion behaviors of microbial...

Fabaceae are important crops for their protein-rich seeds, which are essential for human and animal nutrition. They also play a significant role in agriculture as green manures or in crop rotations by fixing atmospheric nitrogen through root symbiosis with rhizobacteria, thus reducing the need for nitrogen fertilizers. This is exemplified by...

Little is known about the responses of plant roots to filamentous pathogens, particularly to oomycetes. To assess the molecular dialog established between the host and the pathogen during early stages of infection, we investigated the overall changes in gene expression in A. thaliana roots challenged with P. parasitica. We analyzed various...

Background: Oomycetes are a group of filamentous microorganisms that includes both animal and plant pathogens and causes major agricultural losses. Phytophthora species can infect most crops and plants from natural ecosystems. Despite their tremendous economic and ecologic importance, few effective methods exist for limiting the damage caused...

Doctoral

Pathogenic oomycetes have evolved RXLR effectors to thwart plant defense mechanisms and invade host tissues. We analysed the function of one of these effectors (Penetration-Specific Effector 1 (PSE1)) whose transcript is transiently accumulated during penetration of host roots by the oomycete Phytophthora parasitica. Expression of PSE1 protein...