Figure 6
From: A conserved juxtacrine signal regulates synaptic partner recognition in Caenorhabditis elegans
Limiting amounts of UNC-6/Netrin promote SPR through a juxtacrine signal from postsynaptic to presynaptic neurons. In this model, UNC-6 secreted from AVA interneurons binds UNC-40 expressed in PHB neurons to direct SPR. Limiting amounts of UNC-6 sequestered near the AVA membrane bind a subset of the available UNC-40 receptors in PHB, inducing a recognition event that results in correct adhesion and synaptogenesis between the two neurons.