Ephrin Bs and canonical Reelin signalling.

mice exhibit loss of the signaling protein Reelin (Reln) which affects radial pyramidal neuron migration and results in cortical layer malformation. During cortical development Eph receptor/ephrin ligand (Eph/Efn) cell-cell interactions are important for neuronal migration, axonal/dendritic growth, synaptogenesis, and pruning. Recently it has been claimed that Ephb/Efnb and Reln pathways interact genetically and layering defects in triple mutants and compound mice are similar to those present in . Here we demonstrate that contrary to this previous report the compound mutant as well as the triple mutant do not show defects of cortical layering or elevated Dab1 levels. While protein-protein interactions between Efnbs and Reln have been confirmed, they do not affect the radial positioning of migrating neocortical pyramidal neurons.