在HEK293细胞中,GPCR介导的Ca2+调动激活的各种途径
Francesco De Pascali1, Asuka Inoue2, Jeffrey L Benovic1
1Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
The Journal of biological chemistry
|October 12, 2024
概括
G蛋白结合受体 (GPCRs) 调解细胞反应. 这项研究揭示了Gs合受体的独特途径,如β2-上腺素受体 (β2AR),EP2和EP4受体,以在HEK293细胞中调动 (Ca2+).
科学领域:
- 细胞信号传输 细胞信号传输
- 分子药理学分子药理学
- G 蛋白结合受体的受体.
背景情况:
- G蛋白结合受体 (GPCRs) 对于信号传导至关重要.
- (Ca2+) 在细胞信号传输中起到关键的第二信使作用.
- 对Ca2+的正规GPCR通路涉及Gαq和Gβγ子单元,激活脂酶C-β (PLCβ).
研究的目的:
- 研究Gs合受体调解Ca2+调动的机制.
- 为了比较HEK293细胞中β2-上腺素受体 (β2AR),EP2受体 (EP2R) 和EP4受体 (EP4R) 使用的信号通路.
主要方法:
- 使用了表达特定GPCRs的人类胚胎293 (HEK293) 细胞.
- 采用了G蛋白子单元 (Gs,Gi,Gq) 和PLCβ的遗传和药理抑制.
- 应用了选择性抑制剂 (YM-254890) 和百日咳毒素.
- 进行生物发光共振能量转移 (BRET) 测试以评估受体-G蛋白相互作用.
主要成果:
- 通过β2AR介导的Ca2+调动主要涉及Gq,独立于Gs或Gi.
- 由EP2R诱导的Ca2+调动对百日咳毒素 (Gi) 敏感,但对Gq抑制不敏感.
- 通过EP4R介导的Ca2+调动对百日咳毒素 (Gi) 和Gq抑制都很敏感.
- 对于Ca2+调动的EP2R和EP4R信号都取决于Gs和PLCβ.
结论:
- 在HEK293细胞中,β2AR利用Gq依赖的Ca2+调动途径.
- EP2R和EP4R使用不同的G蛋白通路,EP2R依赖Gs/Gi,EP4R依赖Gs/Gi/Gq.
- 这些发现突出了在HEK293细胞中Ca2+调动的差异性GPCR信号机制.
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