ATP is required at an early step in compensatory endocytosis in synaptic terminals
ATP is required at an early step in compensatory endocytosis in synaptic terminals
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DOI：
10.1523/jneurosci.21-17-06467.2001
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发表时间：
2001-09-01
影响因子：
5.3
通讯作者：
Heidelberger, R
中科院分区：
文献类型：
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作者：
Heidelberger, R
全终端电容测量被用来检查膜检索以下Ca 2+触发胞吐在单个突触终端。胞吐作用之后，内吞作用只有当内部溶液中含有ATP的水解类似物。ATP-γ-S是一种水解性差的ATP类似物，不支持内吞作用，但对膜修复产生快速而深刻的抑制作用。在类似的条件下，GTP类似物GTP-γ-S和GDP-β-S未能阻断内吞作用，表明ATP是优选的底物。此外，对ATP的需求不依赖于ATP调节胞内Ca ~（2+）的作用，Ca ~（2+）在胞吞中的作用与ATP不同。结果表明，在突触末梢的代偿性快速内吞作用中，ATP水解是一种直接的、急性的需要。考虑到电容技术检测膜表面积的变化，ATP必须是膜分裂步骤或膜分裂的先决条件。
Whole-terminal capacitance measurements were used to examine membrane retrieval that follows Ca2+-triggered exocytosis in single synaptic terminals. Exocytosis was followed by endocytosis only when the internal solution contained a hydrolyzable analog of ATP. ATP-gamma -S, a poorly hydrolyzable ATP analog, did not support endocytosis but instead produced a rapid and profound inhibition of membrane retrieval. Under similar conditions, the GTP analogs GTP-gamma -S and GDP-beta -S failed to block endocytosis, suggesting that ATP is the preferred substrate. Furthermore, the requirement for ATP was independent of the role of ATP in regulating intraterminal Ca2+, and the role of Ca2+ in endocytosis was different from that of ATP. The results suggest a direct, acute requirement for ATP hydrolysis in compensatory fast endocytosis in synaptic terminals. Given that the capacitance technique detects changes in membrane surface area, ATP must be required for the membrane fission step or at a step that is a prerequisite for membrane fission.