Embryogenesis

                                     Arabidopsis Embryogenesis

                                  Comparison of embryo development
                                           in Angiosperms

                  How can such a protected system be investigated experimentally?





 Mutations in the BODENLOS (bdl) and MONOPTEROS (mp) genes lead to very similar deletions of basal
                                          pattern elements

•      mp seedling

                              The bodenlos (bdl) root meristem defect

                        MP encodes for ARF5, an activator of auxin response,
                     whereas BDL encodes for IAA12  the corresponding repressor

                                 Expression patterns of BDL and MP

                                    Model of BDL/MP interaction

                                             BDL/MP act
                       non-cell autonomously to induce hypophyseal cell fate

                             PIN1 efflux carrier localisation suggests
                                 auxin flux towards the hypophysis

                                     Genetic Interference with
                      Auxin Response and Transport Disrupts Embryo Patterning

monopteros

                              GNOM, a putative auxin transport mutant
                     has similar defects in hypophyseal cell fate specification

                                      DR5::GFP  Auxin Reporter

                                    Auxin in Early Embryogenesis

                                              DR5::GFP



                                   DR5::GFP  – in vitro Culturing

                                   DR5::GFP  – in vitro Culturing

                                   DR5::GFP  – in vitro Culturing

                                          Auxin Transport

                                 Molecular Genetics of Auxin Efflux



                                    PIN1 in Early Embryogenesis

                                       PIN7 in Embryogenesis











 Organogenesis





                                Auxin in Flower and Leave Formation

                                   DR5 in Floral Organ Formation

                                   PIN1 in Floral Organ Formation











                                   DR5 in Lateral Root Formation



                                 Relocation > Gradients > Primordia



                                 Common module for organ formation

 Root meristem





































                                   PIN-dependent Auxin Gradients
                                        in Plant Development

















                                    A model of radial patterning