J Biol Chem. 2003 Aug 29;278(35):33492-500. Epub 2003 May 22.
RhoA interaction with inositol 1,4,5-trisphosphate receptor and transient receptor potential channel-1 regulates Ca2+ entry. Role in signaling increased endothelial permeability.
Mehta, D., Ahmmed, G. U., Paria, B. C., Holinstat, M., Voyno-Yasenetskaya, T., Tiruppathi, C., Minshall, R. D., Malik, A. B.,
["Department of Pharmacology, College of Medicine, The University of Illinois, Chicago, Illinois 60612, USA. dmehta@uic.edu"]
["Department of Pharmacology, College of Medicine, The University of Illinois, Chicago, Illinois 60612, USA. dmehta@uic.edu"]
We tested the hypothesis that RhoA, a monomeric GTP-binding protein, induces association of inositol trisphosphate receptor (IP3R) with transient receptor potential channel (TRPC1), and thereby activates store depletion-induced Ca2+ entry in endothelial cells. We showed that RhoA upon activation with thrombin associated with both IP3R and TRPC1. Thrombin also induced translocation of a complex consisting of Rho, IP3R, and TRPC1 to the plasma membrane. IP3R and TRPC1 translocation and association required Rho activation because the response was not seen in C3 transferase (C3)-treated cells. Rho function inhibition using Rho dominant-negative mutant or C3 dampened Ca2+ entry regardless of whether Ca2+ stores were emptied by thrombin, thapsigargin, or inositol trisphosphate. Rho-induced association of IP3R with TRPC1 was dependent on actin filament polymerization because latrunculin (which inhibits actin polymerization) prevented both the association and Ca2+ entry. We also showed that thrombin produced a sustained Rho-dependent increase in cytosolic Ca2+ concentration [Ca2+]i in endothelial cells overexpressing TRPC1. We further showed that Rho-activated Ca2+ entry via TRPC1 is important in the mechanism of the thrombin-induced increase in endothelial permeability. In summary, Rho activation signals interaction of IP3R with TRPC1 at the plasma membrane of endothelial cells, and triggers Ca2+ entry following store depletion and the resultant increase in endothelial permeability.
PMID: 12766172
 Screening
Validation: In vitro validation
Validation: In vivo validation
Characterization
Functional consequence
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Screening
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| Experimental screening | Non-experimental screening | Reference | ||||||||
| TRP channel construct | Interactor source | |||||||||
| TRP channel | Interactor | Method | Species | Region | Species | Organ/tissue | Sample type | |||
| TRPC1 |
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RhoA | Inference | Prediction | 12766172 | |||||
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click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
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click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
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Screening
Validation: In vitro validation
Validation: In vivo validation
Characterization
Functional consequence
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top
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| Validation: In vivo validation
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| Assay with endogenous proteins | Assay with overexpressed proteins | Reference | ||||||||
| Cell or tissue | Cell or tissue | TRP channel construct | Interactor construct | |||||||
| TRP channel | Interactor | Method | Species | Region | Species | Region | ||||
| TRPC1 |
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RhoA | Co-immunoprecipitation | Human pulmonary arterial endothelial cell | 12766172 | |||||
| TRPC1 |
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RhoA | Co-immunofluorescence staining | Human pulmonary arterial endothelial cell | Not used | Not specified | Full-length | 12766172 | ||
(:
click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)
:
click the arrow icon to show interactions only between the corresponding TRP channel and the interactor)