GABAA α4 is expressed in cerebrospinal fluid-contacting neurons and regulates swim behavior in developing zebrafish

GABA _A receptors are present in hindbrain and spinal cord networks, playing a pivotal role in regulating locomotion. In this study, we demonstrate that mutations in the <i>gabra4</i> gene, which encodes the α4 subunit of GABA _A receptors, result in increased swim velocity of larval zebrafish. We also show that this gene is selectively expressed within spinal cord cerebrospinal fluid contacting neurons (CSF-cNs). Given the significance of these neurons in modulating locomotion, our findings support a model in which compromised α4 function leads to an increase in CSF-cN activity, causing a subtle, hyperactive swimming phenotype.