| First Author | Bair AM | Year | 2009 |
| Journal | J Biol Chem | Volume | 284 |
| Issue | 1 | Pages | 563-74 |
| PubMed ID | 18990707 | Mgi Jnum | J:145902 |
| Mgi Id | MGI:3836250 | Doi | 10.1074/jbc.M803984200 |
| Citation | Bair AM, et al. (2009) Ca2+ entry via TRPC channels is necessary for thrombin-induced NF-kappaB activation in endothelial cells through AMP-activated protein kinase and protein kinase Cdelta. J Biol Chem 284(1):563-74 |
| abstractText | The transient receptor potential canonical (TRPC) family channels are proposed to be essential for store-operated Ca2+ entry in endothelial cells. Ca2+ signaling is involved in NF-kappaB activation, but the role of store-operated Ca2+ entry is unclear. Here we show that thrombin-induced Ca2+ entry and the resultant AMP-activated protein kinase (AMPK) activation targets the Ca2+-independent protein kinase Cdelta (PKCdelta) to mediate NF-kappaB activation in endothelial cells. We observed that thrombin-induced p65/RelA, AMPK, and PKCdelta activation were markedly reduced by knockdown of the TRPC isoform TRPC1 expressed in human endothelial cells and in endothelial cells obtained from Trpc4 knock-out mice. Inhibition of Ca2+/calmodulin-dependent protein kinase kinase beta downstream of the Ca2+ influx or knockdown of the downstream Ca2+/calmodulin-dependent protein kinase kinase beta target kinase, AMPK, also prevented NF-kappaB activation. Further, we observed that AMPK interacted with PKCdelta and phosphorylated Thr505 in the activation loop of PKCdelta in thrombin-stimulated endothelial cells. Expression of a PKCdelta-T505A mutant suppressed the thrombin-induced but not the TNF-alpha-induced NF-kappaB activation. These findings demonstrate a novel mechanism for TRPC channels to mediate NF-kappaB activation in endothelial cells that involves the convergence of the TRPC-regulated signaling at AMPK and PKCdelta and that may be a target of interference of the inappropriate activation of NF-kappaB associated with thrombosis. |
