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Updated: Jun 23, 2026
10:13
A Multiplexed Luciferase-based Screening Platform for Interrogating Cancer-associated Signal Transduction in Cultured Cells
Published on: July 3, 2013
Relaxin activates multiple cAMP signaling pathway profiles in different target cells
Michelle L Halls1, Tim D Hewitson, Xiao-Lei Moore
1Department of Pharmacology, Monash University, Clayton, Victoria, Australia.
Annals of the New York Academy of Sciences
|May 7, 2009
Summary
Relaxin
Area of Science:
- Cellular signaling pathways
- Endocrinology
- Molecular biology
Background:
- Relaxin-Family G protein-coupled Receptor 1 (RXFP1) signaling via cyclic adenosine monophosphate (cAMP) is established in HEK293T cells.
- The precise signaling mechanisms of relaxin in native target cells and tissues remain largely undefined.
Purpose of the Study:
- To investigate the endogenous cAMP signaling pathways activated by relaxin through RXFP1 in diverse cell types.
- To determine the cell-type specificity of relaxin-mediated signaling.
Main Methods:
- Screening of seven distinct cell types for endogenous RXFP1 expression.
- Analysis of cAMP accumulation and associated G protein pathway activation (Gαs, Gαi3, GαoB) in response to relaxin stimulation.
Main Results:
- THP-1 cells and rat cardiac fibroblasts activated the Gαi3-Gβγ-phosphatidylinositol 3-kinase-protein kinase Cζ pathway, leading to cAMP increase.
- T-47D cells exclusively activated the Gαs pathway.
- Colo 16 and rat renal fibroblasts activated both Gαs and GαoB pathways.
Conclusions:
- Relaxin-induced signaling via RXFP1 is highly cell-type dependent.
- The observed variations in signaling pathways may explain the diverse physiological effects of relaxin across different tissues.
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