Understanding dorsoventral topography: backwards and forwards

Abstract

Retinal axons project to their central targets along two orthogonal topographic axes, anterior-posterior (A-P) and dorsal-ventral (D-V). While ephrin-A/EphA signaling determines A-P topography, little has been known about the molecular mechanisms guiding axons along the D-V axis. Two papers by Mann et al. and Hindges et al. in this issue of Neuron provide evidence for both forward and reverse ephrin-B/EphB signaling in regulating D-V topography.