Epidermal growth factor signaling through transient receptor potential melastatin 7 cation channel regulates vascular smooth muscle cell function

Zou, Z.-G. et al. (2020) Epidermal growth factor signaling through transient receptor potential melastatin 7 cation channel regulates vascular smooth muscle cell function. Clinical Science, 134(15), pp. 2019-2035. (doi: 10.1042/CS20200827) (PMID:32706027) (PMCID:PMC8299307)

Abstract

Objective: Transient receptor potential (TRP) melastatin 7 (TRPM7) cation channel, a dual-function ion channel/protein kinase, regulates vascular smooth muscle cell (VSMC) Mg2+ homeostasis and mitogenic signaling. Mechanisms regulating vascular growth effects of TRPM7 are unclear, but epidermal growth factor (EGF) may be important because it is a magnesiotropic hormone involved in cellular Mg2+ regulation and VSMC proliferation. Here we sought to determine whether TRPM7 is a downstream target of EGF in VSMCs and if EGF receptor (EGFR) through TRPM7 influences VSMC function. Approach and results: Studies were performed in primary culture VSMCs from rats and humans and vascular tissue from mice deficient in TRPM7 (TRPM7+/Δkinase and TRPM7R/R). EGF increased expression and phosphorylation of TRPM7 and stimulated Mg2+ influx in VSMCs, responses that were attenuated by gefitinib (EGFR inhibitor) and NS8593 (TRPM7 inhibitor). Co-immunoprecipitation (IP) studies, proximity ligation assay (PLA) and live-cell imaging demonstrated interaction of EGFR and TRPM7, which was enhanced by EGF. PP2 (c-Src inhibitor) decreased EGF-induced TRPM7 activation and prevented EGFR–TRPM7 association. EGF-stimulated migration and proliferation of VSMCs were inhibited by gefitinib, PP2, NS8593 and PD98059 (ERK1/2 inhibitor). Phosphorylation of EGFR and ERK1/2 was reduced in VSMCs from TRPM7+/Δkinase mice, which exhibited reduced aortic wall thickness and decreased expression of PCNA and Notch 3, findings recapitulated in TRPM7R/R mice. Conclusions: We show that EGFR directly interacts with TRPM7 through c-Src-dependent processes. Functionally these phenomena regulate [Mg2+]i homeostasis, ERK1/2 signaling and VSMC function. Our findings define a novel signaling cascade linking EGF/EGFR and TRPM7, important in vascular homeostasis.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fuller, Professor Will and Baillie, Professor George and Alves Moreira Lopes, Dr Rheure and Montezano, Dr Augusto and Neves, Dr Karla and Zou, ZhiGuo and Ling, Miss Jiayue and GAO, Xing and Touyz, Professor Rhian and Rios, Dr Francisco and De Lucca Camargo, Ms Livia
• Authors: Zou, Z.-G., Rios, F. J., Neves, K. B., Alves-Lopes, R., Ling, J., Baillie, G. S., Gao, X., Fuller, W., Camargo, L. L., Gudermann, T., Chubanov, V., Montezano, A. C., and Touyz, R. M.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health; College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Clinical Science
• Publisher: Portland Press
• ISSN: 0143-5221
• ISSN (Online): 1470-8736
• Published Online: 24 July 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Clinical Science 134(15): 2019-2035
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
300689		Vascular Noxs as therapeutic targets and biomarkers in hypertension	Rhian Touyz	British Heart Foundation (BHF)	CH/12/4/29762	CAMS - Cardiovascular Science
303944		BHF Centre of Excellence	Rhian Touyz	British Heart Foundation (BHF)	RE/18/6/34217	CAMS - Cardiovascular Science