通过NAADP介导的释放促进了血管蛋白2分泌,通过调节Rab46依赖的韦贝尔-帕拉德体贩运来调节血管蛋白2分泌
Ryan D Murray1, Melissa Rose1, Katarina T Miteva2
1University of Leeds, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds LS2 9JT, UK.
Cell calcium
|August 24, 2025
概括
通过双孔通道 (TPCs) 释放 (Ca2+) 对于从微管组织中心 (MTOC) 脱离含有angiopoietin2 (Ang2) 的囊泡至关重要,从而使Ang2从内皮细胞分泌出来.
科学领域:
- 内皮细胞生物学 内皮细胞生物学
- 分泌的分子机制的分泌.
- 信号传递的.
背景情况:
- ангиопоетин2 (Ang2) 是血管生成的关键调节剂,储存在内皮维贝尔-帕拉德体 (WPB) 中.
- 基因组胺刺激通过通过Rab46.在微管组织中心 (MTOC) 捕获WPBs来延迟Ang2分泌.
- WPB脱离和Ang2分泌需要 (Ca2+) 与Rab46结合,但根本的道尚不清楚.
研究的目的:
- 调查内体双孔通道蛋白 (TPC) 在调节 Ca2+ 信号中对 WPB 脱离和 Ang2 分泌的作用.
- 阐明连接组胺,Ca2+,TPCs,Rab46和Ang2分泌的分子机制.
主要方法:
- 使用Ca2+成像和高分辨率光显微镜.
- 使用药理抑制剂 (Ned-19,四氨酸) 和一个TPC2激动剂 (TPC2-A1-N).
- 评估了Rab46聚类,WPB局部化,以及经过组胺激活后的Ang2分泌.
主要成果:
- TPC 抑制剂增加了 Rab46/WPB 在 MTOC 的聚合,而 TPC2 激动剂则降低了它.
- 由于TPC抑制,由组胺引起的Ang2分泌减少,但由TPC2激动剂增强.
- 这些发现表明TPC通道与WPB-MTOC脱离的Ca2+依赖调节有关.
结论:
- 通过TPC2通道释放由组胺介导的Ca2+对于Rab46依赖的WPB脱离MTOC至关重要.
- 通过TPC介导的Ca2+信号直接调节从内皮细胞释放的angiopoietin2.
- 这项研究揭示了一种控制Ang2分泌的新机制,并提供了潜在的治疗点.
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