Vesicle endocytosis requires dynamin-dependent GTP hydrolysis at a fast CNS synapse.
Molecular dependence of vesicular endocytosis was investigated with capacitance measurements at the calyx of Held terminal in brainstem slices. Intraterminal loading of botulinum toxin E revealed that the rapid capacitance transient implicated as "kiss-and-run" was unrelated to transmitter release. The release-related capacitance change decayed with an endocytotic time constant of 10 to 25 seconds, depending on the magnitude of exocytosis. Presynaptic loading of the nonhydrolyzable guanosine 5'-triphosphate (GTP) analog GTPgS or dynamin-1 proline-rich domain peptide abolished endocytosis. These compounds had no immediate effect on exocytosis, but caused a use-dependent rundown of exocytosis. Thus, the guanosine triphosphatase dynamin-1 is indispensable for vesicle endocytosis at this fast central nervous system (CNS) synapse.
Yamashita
Takayuki
T
Department of Neurophysiology, University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan.
Hige
Toshihide
T
Takahashi
Tomoyuki
T
D000818:Animals; D001905:Botulinum Toxins / Q000378:metabolism; D001933:Brain Stem / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D034284:Dynamin I / Q000494:pharmacology / Q000502:physiology*; D025802:Electric Capacitance; D004705:Endocytosis; D019706:Excitatory Postsynaptic Potentials; D005089:Exocytosis; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006153:Guanosine Diphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000378:metabolism*; D006868:Hydrolysis; D066298:In Vitro Techniques; D018408:Patch-Clamp Techniques; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission; D013572:Synaptic Vesicles / Q000378:metabolism*; D013873:Thionucleotides / Q000494:pharmacology
D010446:Peptide Fragments; D013873:Thionucleotides; D006153:Guanosine Diphosphate; D016244:Guanosine 5'-O-(3-Thiotriphosphate); C023427:guanosine 5'-O-(2-thiodiphosphate); D006160:Guanosine Triphosphate; D001905:Botulinum Toxins; D034284:Dynamin I; D002118:Calcium; C096326:botulinum toxin type E