在体外核囊泡融合需要动员:对膜流量和IP3受体功能的影响
K M Sullivan1, W B Busa, K L Wilson
1Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Cell
|July 2, 1993
概括
在Xenopus蛋提取物中的核囊泡融合需要离子 (Ca2+) 梯度. 酸信号传递,特别是伊诺西1,4,5-三酸盐 (IP3),调节了这种依赖Ca2+的融合过程.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 核囊泡融合对于核外的形成和维护至关重要.
- 离子 (Ca2+) 是众所周知的各种细胞过程的调节者,包括膜融合.
研究的目的:
- 为了研究离子和氨酸信号在Xenopus蛋提取物中的核囊泡融合中的作用.
- 为了确定参与调节核囊泡融合的特定信号通路.
主要方法:
- 使用Xenopus蛋提取物在体外研究核囊泡融合.
- 采用BAPTA,一个Ca2+化剂,以抑制聚变并评估Ca2+梯度的作用.
- 使用伊诺西1,4,5-三酸盐 (IP3) 和肝素来探测IP3受体和类酸信号的参与.
主要成果:
- 聚变被BAPTA抑制,表明需要细胞质Ca2+梯度.
- 这一依赖Ca2+的步骤与ADP-ribosylation因子介导的步骤不同.
- 外源的IP3挽救了BAPTA抑制的融合,这表明IP3信号的作用.
- 氨酸阻断了融合,证实了IP3受体的参与,而这种抑制在IP3时是可逆的.
结论:
- 细胞质Ca2+梯度对于核囊泡融合至关重要.
- 通过伊诺西1,4,5-三酸盐及其受体介导的酸信号传递,在核囊泡融合中起着调节作用.
- 这些发现突出了控制核膜动态的新型信号通路.
相关概念视频
Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...


