Effective Sensory Modality Activating an Escape Triggering Neuron Switches during Early Development in Zebrafish
- Authors
- Kohashi, T., Nakata, N., and Oda, Y.
- ID
- ZDB-PUB-120430-18
- Date
- 2012
- Source
- The Journal of neuroscience : the official journal of the Society for Neuroscience 32(17): 5810-5820 (Journal)
- Registered Authors
- Oda, Yoichi
- Keywords
- none
- MeSH Terms
-
- Action Potentials/physiology
- Afferent Pathways/growth & development*
- Afferent Pathways/physiology
- Age Factors
- Animals
- Animals, Genetically Modified
- Behavior, Animal/physiology
- ELAV Proteins/metabolism
- Escape Reaction/physiology*
- Green Fluorescent Proteins/genetics
- Head/innervation
- LIM-Homeodomain Proteins/genetics
- Larva
- Laser Therapy/methods
- Neurons/physiology*
- Organic Chemicals/metabolism
- Physical Stimulation
- Reaction Time/physiology
- Statistics, Nonparametric
- Time Factors
- Transcription Factors/genetics
- Trigeminal Ganglion/cytology
- Trigeminal Ganglion/growth & development
- Trigeminal Nerve/physiology
- Vestibule, Labyrinth/growth & development*
- Vestibule, Labyrinth/injuries
- Zebrafish
- PubMed
- 22539843 Full text @ J. Neurosci.
Developing nervous systems grow to integrate sensory signals from different modalities and to respond through various behaviors. Here, we examined the development of escape behavior in zebrafish [45–170 h postfertilization (hpf)] to study how developing sensory inputs are integrated into sensorimotor circuits. Mature fish exhibit fast escape upon both auditory/vestibular (AV) and head-tactile stimuli. Newly hatched larvae, however, do not respond to AV stimuli before 75 hpf. Because AV-induced fast escape in mature fish is triggered by a pair of hindbrain neurons known as Mauthner (M) cells, we studied functional development of the M-cell circuit accounting for late acquisition of AV-induced escape. In fast escape elicited by head-directed water jet, minimum onset latency decreased throughout development (5 ms at 45–59 hpf, 3 ms after 75 hpf). After 75 hpf, lesioning the otic vesicle (OV) to eliminate AV input resulted in loss of short-latency (<5 ms) fast escape, whereas ablation of the sensory trigeminal ganglion (gV) to block head-tactile input did not. Before 75 hpf, however, fast escape persisted after OV lesion but disappeared after gV ablation. Laser ablation of the M-cell and Ca2+ imaging of the M-cell during escape demonstrated that M-cell firing is required to initiate short-latency fast escapes at every developmental stage and further suggest that head-tactile input activates the M-cell before 75 hpf, but that after this point AV input activates the M-cell instead. Thus, a switch in the effective sensory input to the M-cells mediates the acquisition of a novel modality for initiating fast escape.