Dataset Information

Matrix Rigidity-Dependent Regulation of Ca2+ at Plasma Membrane Microdomains by FAK Visualized by Fluorescence Resonance Energy Transfer.

ABSTRACT: The dynamic regulation of signal transduction at plasma membrane microdomains remains poorly understood due to limitations in current experimental approaches. Genetically encoded biosensors based on fluorescent resonance energy transfer (FRET) can provide high spatiotemporal resolution for imaging cell signaling networks. Here, distinctive regulation of focal adhesion kinase (FAK) and Ca2+ signals are visualized at different membrane microdomains by FRET using membrane-targeting biosensors. It is shown that rigidity-dependent FAK and Ca2+ signals in human mesenchymal stem cells (hMSCs) are selectively activated at detergent-resistant membrane (DRM or rafts) microdomains during the cell-matrix adhesion process, with minimal activities at non-DRM domains. The rigidity-dependent Ca2+ signal at the DRM microdomains is downregulated by either FAK inhibition or lipid raft disruption, suggesting that FAK and lipid raft integrity mediate the in situ Ca2+ activation. It is further revealed that transient receptor potential subfamily M7 (TRPM7) participates in the mobilization of Ca2+ signals within DRM regions. Thus, the findings provide insights into the underlying mechanisms that regulate Ca2+ and FAK signals in hMSCs under different mechanical microenvironments.

SUBMITTER: Kim TJ

PROVIDER: S-EPMC6382294 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Matrix Rigidity-Dependent Regulation of Ca<sup>2+</sup> at Plasma Membrane Microdomains by FAK Visualized by Fluorescence Resonance Energy Transfer.

Kim Tae-Jin TJ Lei Lei L Seong Jihye J Suh Jung-Soo JS Jang Yoon-Kwan YK Jung Sang Hoon SH Sun Jie J Kim Deok-Ho DH Wang Yingxiao Y

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20181218 4

The dynamic regulation of signal transduction at plasma membrane microdomains remains poorly understood due to limitations in current experimental approaches. Genetically encoded biosensors based on fluorescent resonance energy transfer (FRET) can provide high spatiotemporal resolution for imaging cell signaling networks. Here, distinctive regulation of focal adhesion kinase (FAK) and Ca<sup>2+</sup> signals are visualized at different membrane microdomains by FRET using membrane-targeting biose ...[more]

PMID: 30828523

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Dataset Information

Matrix Rigidity-Dependent Regulation of Ca2+ at Plasma Membrane Microdomains by FAK Visualized by Fluorescence Resonance Energy Transfer.

Publications

Matrix Rigidity-Dependent Regulation of Ca<sup>2+</sup> at Plasma Membrane Microdomains by FAK Visualized by Fluorescence Resonance Energy Transfer.

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