title: Anatomical coupling of sensory and motor nerve trajectory via axon tracking.
abstract: It is a long-standing question how developing motor and sensory neuron projections cooperatively form a common principal grid of peripheral nerve pathways relaying behavioral outputs and somatosensory inputs. Here, we explored this issue through targeted cell lineage and gene manipulation in mouse, combined with in vitro live axon imaging. In the absence of motor projections, dorsal (epaxial) and ventral (hypaxial) sensory projections form in a randomized manner, while removal of EphA3/4 receptor tyrosine kinases expressed by epaxial motor axons triggers selective failure to form epaxial sensory projections. EphA3/4 act non-cell-autonomously by inducing sensory axons to track along preformed epaxial motor projections. This involves cognate ephrin-A proteins on sensory axons but is independent from EphA3/4 signaling in motor axons proper. Assembly of peripheral nerve pathways thus involves motor axon subtype-specific signals that couple sensory projections to discrete motor pathways.
authors.affiliation: Developmental Neurobiology Laboratory, European Neuroscience Institute (ENI-G), Grisebachstraße 5, 37077 Göttingen, Germany.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Klein
authors.forename: Binhai
authors.initials: B
authors.lastname: Zheng
authors.forename: Till
authors.initials: T
authors.lastname: Marquardt
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects / Q000378:metabolism*; D004622:Embryo, Mammalian; D005727:Ganglia, Spinal / Q000166:cytology; D049452:Green Fluorescent Proteins / Q000235:genetics; D018398:Homeodomain Proteins / Q000235:genetics; D066298:In Vitro Techniques; D051379:Mice; D008822:Mice, Transgenic; D009046:Motor Neurons / Q000166:cytology*; D020932:Nerve Growth Factor / Q000378:metabolism; D009414:Nerve Growth Factors / Q000378:metabolism; D017933:Peripheral Nervous System / Q000166:cytology*; D036121:Receptor, EphA3 / Q000378:metabolism / Q000494:pharmacology; D011984:Sensory Receptor Cells / Q000166:cytology*; D050819:Transcription Factor Brn-3A / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D014404:Tubulin / Q000378:metabolism
chemical_list: D018398:Homeodomain Proteins; D009414:Nerve Growth Factors; C494189:Pou4f1 protein, mouse; D050819:Transcription Factor Brn-3A; D014157:Transcription Factors; D014404:Tubulin; C462941:beta3 tubulin, mouse; C485184:enhanced green fluorescent protein; C518911:neurotropin 3, mouse; C084059:Hb9 protein, mouse; D049452:Green Fluorescent Proteins; D020932:Nerve Growth Factor; C491717:Epha3 protein, mouse; D036121:Receptor, EphA3