活动依赖的IGF-1外细胞分裂是由Ca2+传感器synaptotagmin-10控制的
Peng Cao1, Anton Maximov, Thomas C Südhof
1Department of Molecular and Cellular Physiology, and Howard Hughes Medical Institute, Stanford University, 1050 Arastradero Rd., Palo Alto, California 94305, USA.
Cell
|April 19, 2011
概括
合成10 (Syt10) 作为传感器,触发嗅球神经元的胰岛素样生长因子-1 (IGF-1) 分泌. 这一发现揭示了神经元中依赖的外细胞形成的新途径.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 突触胺 (Syts) 是已知的Ca(2+) 传感器,用于表细胞突变,其中Syt1,Syt2,Syt7和Syt9具有特征.
- 其他Syt家族成员的功能,包括Syt10在外细胞形成中的功能,在很大程度上是未知的.
研究的目的:
- 为了研究Syt10在嗅球神经元中的功能.
- 确定负责活动依赖IGF-1分泌的Ca2+) 传感器.
主要方法:
- 研究了Syt10在嗅觉球泡神经元中的作用,使用遗传删除 (淘汰赛) 和外源IGF-1救援.
- 检查了Syt10与IGF-1在体膜囊中的局部化.
- 研究了由Syt10触发的IGF-1的Ca(2+) 依赖的表细胞分裂.
主要成果:
- 嗅球神经元通过一种活动依赖的外细胞分裂途径分泌IGF-1.
- 在这些神经元中,Syt10充当IGF-1外细胞形成的Ca2+传感器.
- 删除Syt10导致神经元变小,突触数量减少,以及IGF-1分泌受损,而外源IGF-1可以逆转这种情况.
- Syt10在囊泡中与IGF-1结合,并通过Ca2+触发的IGF-1分泌物进行介导.
结论:
- 在嗅球神经元中,Syt10调节了一种新的,以前未被识别的,依赖于Ca2+的IGF-1外细胞形成途径.
- 这种Syt10介导的途径与Syt1控制的突触囊泡外细胞形成不同.
- 神经元可以利用不同的突触胺来调节功能上单独的Ca2+依赖的膜融合事件.
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