Figure 7.

Models of Eph signaling in amphid axon guidance. (A) Possible relationships between EFN-1, VAB-1, and the PI3K and ABL-1 pathways in axon guidance. (B) Model for the left–right bias in Eph signaling. Amphid guidance on the left side of the animal is mediated by a VAB-1 kinase-dependent signaling pathway. In the presence of EFN-1, EFN-2 inhibits ventral guidance. In the absence of EFN-1, EFN-2 can promote signaling. The right side relies mostly on a kinase-independent signaling mechanism that is inhibited by EFN-2.