Function of neuromuscular synapses in the zebrafish choline-acetyltransferase mutant bajan.

ABSTRACT: We have identified a zebrafish mutant line, bajan, in which compromised motility and fatigue result from a point mutation in the gene coding choline acetyltransferase (ChAT), the enzyme responsible for acetylcholine (ACh) synthesis. Although the mutation predicts loss of ChAT function, bajan inexplicably retains low levels of neuromuscular transmission. We exploited this residual activity and determined the consequences for synaptic function. The attenuated synaptic responses were a direct consequence of a decrease in both resting mean quantal size and quantal content. To replicate behavioral fatigue in swimming, motorneurons were stimulated at high frequencies. A prominent reduction in quantal content, reflecting vesicle depletion, was coincident with a small additional reduction in quant

SUBMITTER: Wang M 

PROVIDER: S-EPMC2576202 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature