血管新生受限于由LIC1介导的溶酶体贩运
Dymonn Johnson1, Sarah Colijn1, Jahmiera Richee1
1Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO, 63110, USA.
Angiogenesis
|October 2, 2024
概括
滴氨酸细胞质1轻中间链1 (LIC1) 通常限制新的血管生长. 斑马鱼和人类细胞中LIC1功能的丧失通过破坏VEGFR2降解来促进过度血管生成.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- 丁氨酸细胞质1轻中间链1 (LIC1) 对丁氨酸电机复合体至关重要,影响内体循环和溶酶体降解.
- LIC1与Rab蛋白和RILPL1/2等适应蛋白相互作用,影响货物运输和细胞过程.
- 这些通路的失调会影响细胞功能,包括血管生成,新血管的形成.
研究的目的:
- 研究LIC1在调节血管生成中的作用.
- 了解LIC1影响血管生成的分子机制,特别是关于VEGFR2的贩运和信号传递.
- 探索Rab蛋白和RILPL1/2在LIC1介导的血管生成调节中的参与.
主要方法:
- 产生和分析一个带有过早停止代码的动态斑马鱼突变体.
- 使用LIC1缺乏的人体内皮细胞进行体外研究,以评估VEGFR2水平,SRC酸化和Rab11活性.
- 在体内实验包括内皮特异性表达活性Rab11a和对rilpl1/2.2.中的斑马鱼突变体的分析.
主要成果:
- 斑马鱼突变体表现出增加的血管生成.
- 缺少LIC1的人体内皮细胞显示细胞表面VEGFR2升高,SRC酸化增加,并增强了Rab11介导的循环.
- 斑马鱼的内皮Rab11a激活和rilpl1/2中的突变也导致了过度的血管生成,模仿LIC1缺乏.
结论:
- 与RILPL1/2一起,LIC1通过促进含有VEGFR2的循环内体的降解来限制血管生成.
- 破坏LIC1和RILPL1/2-介导的溶酶体向增强了Rab11依赖的循环,导致SRC信号和血管生成的增加.
- 这些发现突出了LIC1在通过调节VEGFR2流通和降解来控制血管生成中的新角色.
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