Cell Membrane Disruption Stimulates NO/PKG Signaling and Potentiates Cell Membrane Repair in Neighboring Cells
AbstractResealing of a disrupted plasma membrane at the micron-diameter range requires Ca2+-regulated exocytosis. Repeated membrane disruptions reseal more quickly than the initial wound, and this potentiation of membrane resealing persists for at least 24 hours after the initial wound. Long-term potentiation of membrane resealing requires CREB-dependent gene expression, which is activated by the PKC- and p38 MAPK-dependent pathway in a wounded cell. The present study demonstrates that membrane resealing is potentiated in both wounded and neighboring cells in MDCK cells. Wounding of cells expressing CREB133, a mutant variant of CREB, does not show the potentiated response of cell membrane resealing in either wounded or neighboring cells. Furthermore, wounding of cells induces CREB phosphorylation, not only in wounded cells, but also in neighboring cells. Inhibition of the nitric oxide/PKG signaling pathway suppresses CREB phosphorylation in neighboring cells, but not in wounded cells. The potentiation of membrane resealing in neighboring cells is suppressed if the nitric oxide/PKG pathway is inhibited during the initial wound. Together, these results suggest that the nitric oxide/PKG pathway stimulates CREB phosphorylation in neighboring cells so that subsequent cell membrane disruptions of the neighboring cells reseal more quickly.
CitationPLoS One. 2012 Aug 7; 7(8):e42885
- Short-term potentiation of membrane resealing in neighboring cells is mediated by purinergic signaling.
- Authors: Togo T
- Issue date: 2014
- Cell membrane disruption stimulates cAMP and Ca<sup>2+</sup> signaling to potentiate cell membrane resealing in neighboring cells.
- Authors: Togo T
- Issue date: 2017 Dec 15
- Cyclic GMP/protein kinase G type-Iα (PKG-Iα) signaling pathway promotes CREB phosphorylation and maintains higher c-IAP1, livin, survivin, and Mcl-1 expression and the inhibition of PKG-Iα kinase activity synergizes with cisplatin in non-small cell lung cancer cells.
- Authors: Wong JC, Bathina M, Fiscus RR
- Issue date: 2012 Nov
- Activation of the small GTPase Rac1 by cGMP-dependent protein kinase.
- Authors: Hou Y, Ye RD, Browning DD
- Issue date: 2004 Sep
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