Project description DEENESFRITPL Shedding light on the ABCs of plant growth When a plant leans towards the sun, it grows towards a light stimulus which is known as phototropism. As a process, it’s initiated by the phototropin blue-light receptors, perceiving light gradients to trigger downstream signalling leading to the asymmetric distribution of the growth hormone auxin across the photo-stimulated stem. The EU-funded THyM project will take a close look at a plant ATP-binding cassette (ABC) protein and its function in phototropism. It will test whether this transporter is necessary for light gradient establishment across the hypocotyl. The findings will deepen our understanding of the light gradient establishment in a plant photosensory organ. Show the project objective Hide the project objective Objective Plants can reorient their growth towards a favorable light environment to optimize photosynthesis in a process called phototropism. This process is initiated by the phototropin blue light receptors, perceiving light gradients to trigger downstream signaling leading to the asymmetric distribution of auxin across the photo-stimulated stem. The Fankhauser lab showed that AtABC, an ABC (ATP-binding cassette) transporter family protein is important for phototropism. AtABC shares homology with Drosophila transporters, which are involved in eye pigment precursor transport and play a vital role in insect vision. In addition to reduced phototropism, Atabc mutants have transparent hypocotyls. The primary objective of this project is to understand the function of AtABC in phototropism and to test whether this transporter is required for light gradient establishment across the hypocotyl. First, I will characterize the Atabc mutant at the tissue, cellular and subcellular levels (e.g. staining for cell wall components) to determine what defect underlies the transparent hypocotyl phenotype. Using several approaches including confocal microscopy to visualize light-activated proteins and fiber-optic techniques, I will measure the light gradient across the hypocotyl of wild type and Atabc mutants. I will characterize phototropin signaling using biochemical and microscopic approaches to determine at which signaling step AtABC is required. To characterize AtABC, I will determine its expression pattern and subcellular localization using GFP-tagged AtABC. Together with the phenotypic characterization of the mutant, this will provide testable hypotheses regarding the substance(s) transported by AtABC. Finally, to determine the functional conservation of AtABC in other plants, I will characterize Brasicca rapa mutants defective in the orthologous gene. The functional characterization of AtABC may provide key insights into light gradient establishment in a plant photosensory organ. Fields of science natural sciencesbiological sciencesbiochemistrybiomoleculesproteinsnatural sciencesphysical sciencesopticsmicroscopyconfocal microscopynatural sciencesbiological sciencesbotany Programme(s) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Topic(s) MSCA-IF-2018 - Individual Fellowships Call for proposal H2020-MSCA-IF-2018 See other projects for this call Funding Scheme MSCA-IF-EF-ST - Standard EF Coordinator UNIVERSITE DE LAUSANNE Net EU contribution € 203 149,44 Address Quartier unil-centre bâtiment unicentre 1015 Lausanne Switzerland See on map Region Schweiz/Suisse/Svizzera Région lémanique Vaud Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00