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The Zebrafish motility mutant twitch once reveals new roles for rapsyn in synaptic function.

ABSTRACT: Upon touch, twitch once zebrafish respond with one or two swimming strokes instead of typical full-blown escapes. This use-dependent fatigue is shown to be a consequence of a mutation in the tetratricopeptide domain of muscle rapsyn, inhibiting formation of subsynaptic acetylcholine receptor clusters. Physiological analysis indicates that reduced synaptic strength, attributable to loss of receptors, is augmented by a potent postsynaptic depression not seen at normal neuromuscular junctions. The synergism between these two physiological processes is causal to the use-dependent muscle fatigue. These findings offer insights into the physiological basis of human myasthenic syndrome and reveal the first demonstration of a role for rapsyn in regulating synaptic function.

SUBMITTER: Ono F

PROVIDER: S-EPMC6758142 | biostudies-literature | 2002 Aug

REPOSITORIES: biostudies-literature

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The Zebrafish motility mutant twitch once reveals new roles for rapsyn in synaptic function.

Ono Fumihito F Shcherbatko Anatoly A Higashijima Shin-ichi S Mandel Gail G Brehm Paul P

The Journal of neuroscience : the official journal of the Society for Neuroscience 20020801 15

Upon touch, twitch once zebrafish respond with one or two swimming strokes instead of typical full-blown escapes. This use-dependent fatigue is shown to be a consequence of a mutation in the tetratricopeptide domain of muscle rapsyn, inhibiting formation of subsynaptic acetylcholine receptor clusters. Physiological analysis indicates that reduced synaptic strength, attributable to loss of receptors, is augmented by a potent postsynaptic depression not seen at normal neuromuscular junctions. The ...[more]

PMID: 12151528

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