Dataset Information

Distinct calcium regulation of TRPM7 mechanosensitive channels at plasma membrane microdomains visualized by FRET-based single cell imaging.

ABSTRACT: Transient receptor potential subfamily M member 7 (TRPM7), a mechanosensitive Ca²⁺ channel, plays a crucial role in intracellular Ca²⁺ homeostasis. However, it is currently unclear how cell mechanical cues control TRPM7 activity and its associated Ca²⁺ influx at plasma membrane microdomains. Using two different types of Ca²⁺ biosensors (Lyn-D3cpv and Kras-D3cpv) based on fluorescence resonance energy transfer, we investigate how Ca²⁺ influx generated by the TRPM7-specific agonist naltriben is mediated at the detergent-resistant membrane (DRM) and non-DRM regions. This study reveals that TRPM7-induced Ca²⁺ influx mainly occurs at the DRM, and chemically induced mechanical perturbations in the cell mechanosensitive apparatus substantially reduce Ca²⁺ influx through TRPM7, preferably located at the DRM. Such perturbations include the disintegration of lipid rafts, microtubules, or actomyosin filaments; the alteration of actomyosin contractility; and the inhibition of focal adhesion and Src kinases. These results suggest that the mechanical membrane environment contributes to the TRPM7 function and activity. Thus, this study provides a fundamental understanding of how the mechanical aspects of the cell membrane regulate the function of mechanosensitive channels.

SUBMITTER: Starostina I

PROVIDER: S-EPMC8429465 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Distinct calcium regulation of TRPM7 mechanosensitive channels at plasma membrane microdomains visualized by FRET-based single cell imaging.

Starostina Irina I Jang Yoon-Kwan YK Kim Heon-Su HS Suh Jung-Soo JS Ahn Sang-Hyun SH Choi Gyu-Ho GH Suk Myungeun M Kim Tae-Jin TJ

Scientific reports 20210909 1

Transient receptor potential subfamily M member 7 (TRPM7), a mechanosensitive Ca2+ channel, plays a crucial role in intracellular Ca2+ homeostasis. However, it is currently unclear how cell mechanical cues control TRPM7 activity and its associated Ca2+ influx at plasma membrane microdomains. Using two different types of Ca2+ biosensors (Lyn-D3cpv and Kras-D3cpv) based on fluorescence resonance energy transfer, we investigate how Ca2+ influx ...[more]

PMID: 34504177

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Dataset Information

Distinct calcium regulation of TRPM7 mechanosensitive channels at plasma membrane microdomains visualized by FRET-based single cell imaging.

Publications

Distinct calcium regulation of TRPM7 mechanosensitive channels at plasma membrane microdomains visualized by FRET-based single cell imaging.

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