Expressing EphA3 in Islet2⁺ RGCs: A) provided additional support for the competition model. B) demonstrated that temporal axon A-P targeting depends on absolute and not relative levels of EphA3. C) demonstrated that temporal axon A-P targeting depends on relative and not absolute levels of EphA3. D) a and b E) a and c

Question

Quizplus · Accepted Answer

This gain-of-function experiment shows that the addition of EphA3 is sufficient to shift temporal axons more anteriorly (relative to neighboring Islet2^- axons that express endogenous levels of EphA3). This results in two distinct maps, with RGCs that express high levels of EphA3 occupying the anterior SCand forcing RGCs that express endogenous levels of EphA3 to target the posterior SC.

Expressing EphA3 in Islet2+ RGCs

Expressing EphA3 in Islet2⁺ RGCs