Glia instruct developmental neuronal remodeling through TGF-β signaling

Abstract

In Drosophila, larval neural circuits are remodeled during metamorphosis by both pruning and neurite remodeling, which requires TGF-β signaling. Here, Awasaki and colleagues find that glia secrete myoglianin, a TGF-β ligand, which upregulates neuronal expression of an ecdysone nuclear receptor that triggers neurite remodeling following the late-larval ecdysone peak. We found that glia secrete myoglianin, a TGF-β ligand, to instruct developmental neural remodeling in Drosophila. Glial myoglianin upregulated neuronal expression of an ecdysone nuclear receptor that triggered neurite remodeling following the late-larval ecdysone peak. Thus glia orchestrate developmental neural remodeling not only by engulfment of unwanted neurites but also by enabling neuron remodeling.