Regulation of cell shape during development of the nervous system

Proper sensory system function requires coordinated development of neurons and their target organs, involving dramatic cell shape changes. Using zebrafish, this study investigates molecular signals driving these processes in the posterior lateral line (pLL), a mechanosensory system. We identify a novel role for Fibroblast Growth Factor (Fgf) in regulating apical constriction via Rho-kinase 2a during rosette formation, essential for neuromast development. Concurrently, we show that JNK-interacting protein 3 (Jip3) mediates axonal outgrowth by enabling Ret receptor transport in afferent neurons. These findings reveal distinct signaling pathways controlling morphogenesis of sensory organs and neurons, advancing understanding of vertebrate sensory development.