Stages and transitions in dendrite arbor differentiation

Neurons connect through dendrite arbors to receive inputs from their appropriate partners. The branching pattern, size, and input distribution in the arbor determine neuron function. Complex nervous system activity depends on creating and wiring a wide diversity of neuron types, each with a characteristic arbor organization. Here we discuss how, by tracking arbor differentiation in vivo, a mature dendrite arbor pattern is derived from the compound outcome of a series of different stages of arbor elaboration. We highlight core stages of elaboration shared between different model systems, and how regulating the transformation between these stages controls the dendrite arbor differentiation process. Finally, we discuss how control over these transformations creates neuron type-specific dendrite arbor morphologies, contributes to nervous system evolution, and is perturbed in disease.