Fig. 2. In vitro guidance of Xenopus retinal axons by ephrin-A5-Fc in the stripe assay. (A) Striped outgrowth of retinal axons is observed when they are given the choice of growing on either ephrin-A5-Fc containing (yellow) or Fc containing lanes (orange). Axons avoid the ephrin-A5 containing lanes. (B) Both stripes have been coated with Fc protein alone. Axons show no preference for either type of lanes. Laminin was used as an outgrowth promoting substratum.