Substrate Control of Dendrite Growth
As animals grow, dendrite arbors of many neurons must expand proportionally to sustain proper connectivity and maintain coverage of their receptive field. Despite the prevalence of this phenomenon, particularly in sensory systems, how dendrite arbor expansion is coordinated with target receptive field expansion is largely unknown. Using genetic screens for mutations that uncouple growth of dendrites and their substrate we have identified a series of substrate-derived cues that coordinate dendrite-substrate growth, in part by restricting dendritic structural plasticity
We have found that physical coupling of epithelial cells and dendrites in the form of dendrite invagination into epithelial cells progressively increases during development, directly coupling dendrite growth to substrate expansion and constraining structural plasticity of dendrites. Notably, similar dendrite-epidermis interactions have been described in diverse sensory systems (worm, fly, fish), suggesting that these mechanisms are likely functional in higher organisms as well.