RT Journal Article
SR Electronic
T1 The organization of the gravity-sensing system in zebrafish
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.07.09.451839
DO 10.1101/2021.07.09.451839
A1 Zhikai Liu
A1 David G.C. Hildebrand
A1 Joshua L. Morgan
A1 Nicholas Slimmon
A1 Martha W. Bagnall
YR 2021
UL http://biorxiv.org/content/early/2021/07/11/2021.07.09.451839.abstract
AB Motor circuits develop in sequence from those governing fast movements to those governing slow. Here we examine whether upstream sensory circuits are organized by similar principles. Using serial-section electron microscopy in larval zebrafish, we generated a complete map of the gravity-sensing (utricular) system from the inner ear to the brainstem. We find that both sensory tuning and developmental sequence are organizing principles of vestibular topography. Patterned rostrocaudal innervation from hair cells to afferents creates a directional tuning map in the utricular ganglion, forming segregated pathways for rostral and caudal tilt. Furthermore, the mediolateral axis of the ganglion is linked to both developmental sequence and temporal kinetics. Early-born pathways carrying phasic information preferentially excite fast escape circuits, whereas later-born pathways carrying tonic signals excite slower postural and oculomotor circuits. These results demonstrate that vestibular circuits are organized by tuning direction and kinetics, aligning them with downstream motor circuits and behaviors.Competing Interest StatementThe authors have declared no competing interest.