Guidance of vascular and neuronal network formation

During evolution animals had to evolve in order to perform more and more complex tasks. For this, they developed two main specialized tissues: a highly branched vascular system to ensure adequate blood supply, and an intricate nervous system to transmit electrical signals to peripheral organs. During development, the patterning of both the vascular and the nervous system is achieved through the coordinated action of a variety of guidance cues that direct the growing nerves and vessels to specific targets. Emerging evidence suggests that the same set of attractive and repulsive molecules drives the migration of both axons and endothelial tip cells, thus playing a central role in the development of an ordered and stereotyped network. In this chapter we will discuss the similarities between axon and blood vessel guidance as well as the evidence showing that molecules first identified as axon guidance cues also play a role in blood vessel guidance.