融合前运动状态决定了大型密核囊泡的膜融合动态的异质性
Renhao Xue1,2, Enming Zhang3, Yu Wang1,2
1Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai Institute of Maternal-Fetal Medicine and Gynecologic Oncology, Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China.
Acta physiologica (Oxford, England)
|February 14, 2024
概括
神经内分泌细胞表现出异质的大型密核囊泡 (LDCV) 融合动态. 受到actin重组影响的融合前运动决定了LDCV是否形成"活跃"或"惰性"池,影响激素释放.
科学领域:
- 细胞生物学 细胞生物学
- 神经内分泌学神经内分泌学
- 膜贩卖 膜贩卖 膜贩卖 膜贩卖
背景情况:
- 神经内分泌细胞中的大密核囊泡 (LDCVs) 通过调节的膜融合释放激素.
- 在LDCV聚变动态中观察到异质性,但聚变前状态的决定因素仍然不清楚.
- 了解LDCV的融合前状态对于破译激素释放调节至关重要.
研究的目的:
- 为了研究前融合状态如何影响LDCV膜融合的异质性.
- 探讨在调解LDCV融合前运动和融合动力学中的actin重组的作用.
主要方法:
- 使用全内部反射光显微镜来评估LDCV亚群的融合前运动.
- 使用Clostridium difficile毒素B (ToxB) 通过阻断活性蛋白重组来选择性地准和分离快速融合囊泡池.
- 研究了活性蛋白重组阻断剂 (ToxB,拉特素A) 对LDCV亚群的影响.
主要成果:
- 确定了两个不同的LDCV亚群:一个具有快速前融合运动的"活跃"池和一个具有限制运动的"惰性"池.
- 托克斯B治疗通过耗尽活性池消除了快速融合囊泡,这种效应没有被醇所挽救.
- 拉特伦库林A是一种较温和的动蛋白阻断剂,部分破坏了活性池,并略微减少了快速融合亚群.
结论:
- 在LDCV中的融合前运动异质性直接影响异质的融合孔动态.
- F-actin网络的重新排列是囊泡前融合运动的关键媒介.
- 随后,由actin介导的囊泡运动决定了膜融合和激素释放的动力学.
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