The intracellular Ca2+ sensitivity of transmitter release in glutamatergic neocortical boutons

• 成果类型: Article
• 署名作者: Bornschein, Grit; Brachtendorf, Simone; Reinert, Anja; Eshra, Abdelmoneim; Kraft, Robert; Hirrlinger, Johannes; Eilers, Jens; Hallermann, Stefan; Schmidt, Hartmut
• 署名单位: Leipzig University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-12149
• DOI: 10.1126/science.adp0870
• 发表日期: 2025-07-03
• 页码: 48-52
• 关键词: neurotransmitter release; pyramidal neurons; developmental regulation; calcium sensitivity; kinetic-properties; synaptic vesicles; cerebellar cortex; dm-nitrophen; synapses; calyx

摘要

Synaptotagmin-1 (Syt1) and Syt2 are the main calcium (Ca2+) sensors triggering synchronous release in the brain. In this work, we studied the mechanisms mediating Syt1-triggered release from neocortical synapses. We measured the Ca2+ dependency of release in layer 5 pyramidal neuron synapses by laser photolysis of caged Ca2+. Release had high Ca2+ affinity and positive cooperativity. Measurements at cerebellar Purkinje cell synapses and kinetic models indicate substantial differences compared with Syt2-triggered release. Our results suggest that Syt1-controlled release machineries are optimized for high reliability at moderate Ca2+ elevations and high plastic controllability.