构成性内部化EP2差异调节G蛋白信号传递
Abigail R Walker1, Holly A Parkin1, Sung Hye Kim1
1Institute of Reproductive and Developmental Biology, Department Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
Journal of molecular endocrinology
|April 19, 2024
概括
EP2受体以构成性的方式内化,影响其信号通路. 这种构成性内部化对EP2受体功能至关重要,并为向治疗提供了潜力.
科学领域:
- 药理学 药理学是指药理学的学科.
- 细胞生物学 细胞生物学
- 内分泌学 在内分泌学.
背景情况:
- 前列腺类G蛋白结合受体 (GPCR) EP2与各种疾病有关,包括子宫内膜异位症,骨质疏松症,肥胖症,早产和癌症.
- 内部化和细胞内贩运对GPCR活性至关重要,但EP2受体的空间信号传递和药理利用仍然不太了解.
研究的目的:
- 研究EP2受体信号的空间编程.
- 确定EP2受体内部化在其下游信号通路中的作用.
- 探索针对EP2受体空间信号的药理潜力.
主要方法:
- 利用三种EP2选择性连接体来激活不同的EP2通路.
- 通过动胺依赖和β-阿雷斯独立的途径研究了EP2受体内部化.
- 评估了EP2受体向早期和非常早期内分泌体 (VEE) 的贩运及其与APPL1.1的相互作用.
- 量化了cAMP和信号传递对EP2受体内部化的依赖.
主要成果:
- EP2受体经历了有限的激素驱动内部化,但是构成性的内部化.
- 构成性EP2受体向VEE的传输不受连接体激活的影响.
- 对某些激动剂的急性cAMP信号的70%左右,受体内化是必不可少的,但对于Gαs偏差激动剂来说,这一比例较小.
- 抑制EP2受体内化部分降低了信号传递,并没有影响PGE2分泌,这表明对激动剂依赖的空间需求.
结论:
- 构成性EP2受体内部化在其信号传递中发挥着关键作用.
- 对于EP2受体Gαs和Gαq/11信号传递,存在着对激动剂依赖的空间要求.
- 这些发现突出了选择性向EP2信号通路的潜力,以获得治疗效益.
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