Cell to Cell signalling and communication during the establishment - PowerPoint PPT Presentation

“Cell to Cell signalling and communication during the establishment of the nitrogen-fixing symbiosis” Martina Beck Incoming fellow 1

Research background: Studying the dynamics of plant signalling processes PostDoc 2010-2014 PhD 2006-2009 TSL, Norwich, U.K. IZMB, University Bonn , Germany Supervision: S. Robatzek Supervision: J. Samaj Root cell signalling Immune receptor signalling

Research background: Studying the dynamics of plant signalling processes PostDoc 2010-2014 PhD 2006-2009 TSL, Norwich, U.K. IZMB, University Bonn , Germany Supervision: S. Robatzek Supervision: J. Samaj Root cell signalling Immune receptor signalling AgreenSkills Project LIPM, Toulouse Group: D. Barker and P. Gamas Root cell signalling during symbiotic plant-microbe interaction

Symbiotic plant-microbe interaction Legume Root Hair Infection Rhizobia N 2 CO 2 ATP ADP NH 3 M. truncatula N 2 fixing nodule • Nitrogen is a limiting factor for plant growth represents 50% of fertilizer demand to improve crop yield • Legumes represent a natural solution to increase nitrogen conc. in plants and soil

Symbiotic plant-microbe interaction Legume Root Hair Infection rhizobia root hair epidermis Rhizobia cortical cells N 2 CO cortical cells 2 ATP ADP NH 3 Cell wall invagination M. truncatula Tubular structure N 2 fixing nodule  Symbiont entry via Infection thread

Signals involved in host cell reprogramming prior infection Root Hair Infection rhizobia root hair epidermis Rhizobia cortical cells cortical cells Cell reorganisation Ca 2+ spiking Gene expresssion N 2 fixing nodule  Specific host cell reprogramming prior to IT entry

How is signalling controlled during infection ? Intercellular connection Cell wall Plasmodesmata root hair Cytoplasma Changes in number and distribution epidermis Cytoplasma cortical cells Changes in pore size • Connection ? cortical cells • Separation ? Cytoplasma ONLY cortical cells connected to RH are signalling Do intercellular connections control molecular flux between cells ?

How is signalling controlled during infection ? (1) Live cell imaging approach  PD localisation, distribution, structure  Molecular flux studies (GFP,Dyes) root hair epidermis cortical cells cortical cells Role of symplastic connections

How is signalling controlled during infection ? (1) Live cell imaging approach  PD localisation, distribution, structure  Molecular flux studies (GFP,Dyes) root hair (2) Gene Candidate approach • Transcriptomic data of epidermis symbiotic tissue  PD localized and regulatory protein cortical cells  Expression pattern/ Localization cortical cells  Functional studies Identification of new regulators for cell-to-cell communication