Les séminaires ont lieu sur le Campus Montpellier Institut Agro/INRA de La Gaillarde (2, place P. Viala Montpellier)
Jeudi 14 septembre 2023 à 14h – Amphi 2 (Bât.2bis)
Miriam Gifford
University of Warwick
Nodules, clocks and roots: communication underground
Legumes house nitrogen-fixing endosymbiotic rhizobia in specialized cells within root nodules. These nodules are factories of metabolic activity whose activity is shaped by the plant, bacteria and environment. Our recent work has approached each of these components in order to understand how nodulation efficiency is shaped and controlled.
Nodules: By characterising microbial communities in Medicago truncatula plants inoculated with different rhizobial strains in three distinct soil types, we found that the rhizobial strain and symbiotic state can shape endosphere composition and plant nutrition. We also identified new microbes whose abundance is associated with more efficient symbiosis.
Clocks: We also found that the efficiency of symbiosis is affected by the plant circadian clock via LATE ELONGATED HYPOCOTYL (LHY) activity. Rhythmic LHY-regulated transcripts in root nodules include a subset of Nodule-specific Cysteine Rich peptides (NCRs) that may coordinate of bacterial activity with the rhythms of the plant host to ensure optimal symbiosis.
Roots: By investigating links between the hormone and genetic signalling networks controlling nodulation and lateral root development we identified new molecular links that can help to better understand non-legume root system architecture as well as that of legumes.
Current research profile/bio: Miriam Gifford’s interests are in studying complex networks involved in plant responses to the environment and plasticity, with a particular focus on modelling cell type specific mechanisms, gene networks enabling symbiosis with rhizobia and currently the impact of the circadian clock on nodulation in the rhizosphere. After postdoctoral work at New York University (USA) she started her lab at Warwick University (UK) in 2009 where she is now Professor and the Head of School of Life Sciences.
Contact : Gabriel Krouk
Contacts IBIP :
Sabine Zimmermann (sabine.zimmermann@cnrs.fr)
Alexandre Martiniere (alexandre.martiniere@cnrs.fr)
Aude Coupel-Ledru (aude.coupel-ledru@inrae.fr)
Chantal Baracco (chantal.baracco@inrae.fr)