LAR receptor tyrosine phosphatases and HSPGs guide peripheral sensory axons to the skin.

Background: Peripheral axons of somatosensory neurons innervate the skin early in development to detect touch stimuli. Embryological experiments had suggested that the skin produces guidance cues that attract sensory axons, but neither the attractants nor their neuronal receptors had previously been identified.

Results: To investigate peripheral axon navigation to the skin, we combined live imaging of developing zebrafish Rohon-Beard (RB) neurons with molecular loss-of-function manipulations.

Vesicular glutamate transporter 3 is required for synaptic transmission in zebrafish hair cells.

Hair cells detect sound and movement and transmit this information via specialized ribbon synapses. Here we report that asteroid, a gene identified in an ethylnitrosourea mutagenesis screen of zebrafish larvae for auditory/vestibular mutants, encodes vesicular glutamate transporter 3 (Vglut3). A splice site mutation in exon 2 of vglut3 results in a severe truncation of the predicted protein product and morpholinos directed against the vglut3 ATG start site or the affected splice junction replicate the asteroid phenotype.