细胞内的GPCR选择性影响通过cAMP / PKA级联通过细胞信号传递
Emily E Blythe1, Rita R Fagan2, Mark von Zastrow3
1Department of Psychiatry and Behavioral Sciences, University of California, San Francisco, San Francisco, CA, USA; Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN, USA.
The Journal of biological chemistry
|February 7, 2026
概括
内细胞分裂通过创建一个独特的cAMP代码来区分G蛋白结合受体 (GPCR) 信号传递. 这种空间时间代码依赖于GPCR内部化,通过蛋白激酶A (PKA) 激活影响基因转录.
科学领域:
- 细胞生物学 细胞生物学
- 分子药理学分子药理学
- 信号传输 信号传输
背景情况:
- G蛋白结合受体 (GPCRs) 通过像cAMP/蛋白激酶A (PKA) 这样的级联信号.
- 虽然GPCR内细胞分裂会影响信号持续时间和下游效应,但其在共表达受体中的作用尚不清楚.
- 细胞环境和受体内化速率各不相同,影响cAMP信号输出结果.
研究的目的:
- 调查细胞内是否使同表达的Gs-合的GPCRs的信号配置有所差异.
- 为了比较内细胞分裂在cAMP生产,PKA激活和VIPR1,β2AR和A2BR的基因转录中的作用.
- 确定GPCR内部化如何影响cAMP信号的时空动态.
主要方法:
- 使用了人类脏衍生的 (HEK293) 细胞,表达内源性VIPR1,β2AR和A2BR.
- 测量了全球cAMP升高,细胞质PKA活动和核PKA激活.
- 经激素激发后评估的转录诱导.
- 与GPCR内细胞化和没有GPCR内细胞化进行信号结局的比较.
主要成果:
- VIPR1和β2AR内部化显著延长了细胞质PKA活性,而A2BR没有.
- 观察到对VIPR1和β2AR的核PKA激活和转录诱导,但没有A2BR.
- 在中间或下游阶段,A2BR在信号持续时间方面对内细胞分裂的依赖程度很小.
结论:
- 细胞内核突变对内源性共同表达的GPCRs的信号配置进行了关键的区分.
- 不同GPCR内部化程序一个时空cAMP代码.
- 这种代码由细胞质PKA的近距离空间解码,并由细胞核暂时解释,从而影响基因转录.
相关概念视频
Intracellular Signaling Cascades
53.7K
Once a ligand binds to a receptor, the signal is transmitted through the membrane and into the cytoplasm. The continuation of a signal in this manner is called signal transduction. Signal transduction only occurs with cell-surface receptors, which cannot interact with most components of the cell, such as DNA. Only internal receptors can interact directly with DNA in the nucleus to initiate protein synthesis. When a ligand binds to its receptor, conformational changes occur that affect the...
53.7K
MAPK Signaling Cascades
8.5K
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
8.5K
Amplifying Signals via Enzymatic Cascade
18.6K
When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze...
18.6K
Endocrine Signaling
68.2K
Endocrine cells produce hormones to communicate with remote target cells found in other organs. The hormone reaches these distant areas using the circulatory system. This exposes the whole organism to the hormone but only those cells expressing hormone receptors or target cells are affected. Thus, endocrine signaling induces slow responses from its target cells but these effects also last longer.
68.2K
Cell-surface Signaling
54.6K
Hormones—or any molecule that binds to a receptor, known as a ligand—that are lipid-insoluble (water-soluble) are not able to diffuse across the cell membrane. In order to be able to affect a cell without entering it, these hormones bind to receptors on the cell membrane. When a first messenger, a hormone, binds to a receptor, a signal cascade is set off, causing second messengers, proteins inside the cell, to become activated, resulting in downstream effects.
54.6K
Receptor-mediated Endocytosis
111.1K
Overview
111.1K


