Lay summary
This grant allocated to the Dept. of Biology, Univ. of Fribourg, is based on a joint application from seven of its groups.Neural basis of chemosensory learning in the Drosophila larva (A. Thum, R. Stocker): attempts to dissect the chemosensory circuit of the fly larva, from sensory neurons to higher brain centers which form associations of odors with reinforcing stimuli, and to motor areas that trigger appropriate behaviors. In vivo imaging will bridge the gap between anatomical and behavioral approaches.Analysis of the neuronal network in the Drosophila larval visual system (S. Sprecher): intends to map the synaptic connectivity between larval photoreceptor neurons and their central targets. It will lay ground for behavioral studies addressing the functional role of photoreceptor subtypes and their downstream neuronal network. Visualizing complex neuronal structures and synaptic connectivity requires high-resolution confocal microscopy which also sets stage for calcium imaging of identified neurons. Developmental role of the chromatin remodelers LET-418 and CHD-3 in C. elegans (F. Müller, C. Wicky): will investigate the cellular and developmental functions of two C. elegans orthologs of the eukaryotic Mi-2 protein family, which is involved in chromatin remodeling.Analysis of cell fate in the C. elegans germ line (A. Puoti): seeks to uncover the precise localization of germ line-associated proteins and chromosomal structures in C. elegans, in order to understand how gene products orchestrate germ line development.Analysis of the intracellular stages of mycorrhizal symbiosis in plants (D. Reinhardt): focuses on the invasion of a microbial symbiont in epidermal and cortical root cells. The goal is to study in vivo the subcellular localization of proteins involved in mycorrhizal symbiosis, together with fungal structures and surrounding plant cells.Molecular and cytological analysis of disease resistance of the model plant Arabidopsis (F. Mauch): studies host-pathogen interactions at the cellular level using an Arabidopsis-P. brassicae pathosystem. It attempts to demonstrate in planta the movements and interactions of proteins at the subcellular level or the pathogen-triggered movement of organelles.Studies on the localization and function of AtGRXS13, a potential effector of Botrytis cinerea (J.P. Métraux): searches to understand how host plants are diverted from their normal defense reactions by virulent pathogens. Candidate target genes for virulence effectors of the pathogen have been identified. A careful localization of target proteins at high resolution and the study of their interactions are essential for further progress in the field.