Unexpected role of the copper transporter ATP7A in PDGF-induced vascular smooth muscle cell migration

Takashi Ashino, Varadarajan Sudhahar, Norifumi Urao, Jin Oshikawa, Gin Fu Chen, Huan Wang, Yuqing Huo, Lydia Finney, Stefan Vogt, Ronald D. McKinney, Edward B. Maryon, Jack H. Kaplan, Masuko Ushio-Fukai, Tohru Fukai

Research output: Contribution to journalArticlepeer-review

65 Scopus citations

Abstract

Rationale: Copper, an essential nutrient, has been implicated in vascular remodeling and atherosclerosis with unknown mechanism. Bioavailability of intracellular copper is regulated not only by the copper importer CTR1 (copper transporter 1) but also by the copper exporter ATP7A (Menkes ATPase), whose function is achieved through copper-dependent translocation from trans-Golgi network (TGN). Platelet-derived growth factor (PDGF) promotes vascular smooth muscle cell (VSMC) migration, a key component of neointimal formation. Objective: To determine the role of copper transporter ATP7A in PDGF-induced VSMC migration. Methods and results: Depletion of ATP7A inhibited VSMC migration in response to PDGF or wound scratch in a CTR1/copper-dependent manner. PDGF stimulation promoted ATP7A translocation from the TGN to lipid rafts, which localized at the leading edge, where it colocalized with PDGF receptor and Rac1, in migrating VSMCs. Mechanistically, ATP7A small interfering RNA or CTR small interfering RNA prevented PDGF-induced Rac1 translocation to the leading edge, thereby inhibiting lamellipodia formation. In addition, ATP7A depletion prevented a PDGF-induced decrease in copper level and secretory copper enzyme precursor prolysyl oxidase (Pro-LOX) in lipid raft fraction, as well as PDGF-induced increase in LOX activity. In vivo, ATP7A expression was markedly increased and copper accumulation was observed by synchrotron-based X-ray fluorescence microscopy at neointimal VSMCs in wire injury model. Conclusions: These findings suggest that ATP7A plays an important role in copper-dependent PDGF-stimulated VSMC migration via recruiting Rac1 to lipid rafts at the leading edge, as well as regulating LOX activity. This may contribute to neointimal formation after vascular injury. Our findings provide insight into ATP7A as a novel therapeutic target for vascular remodeling and atherosclerosis.

Original languageEnglish (US)
Pages (from-to)787-799
Number of pages13
JournalCirculation research
Volume107
Issue number6
DOIs
StatePublished - Sep 17 2010
Externally publishedYes

Keywords

  • copper transporter
  • migration
  • platelet-derived growth factor
  • vascular remodeling
  • vascular smooth muscle

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Fingerprint

Dive into the research topics of 'Unexpected role of the copper transporter ATP7A in PDGF-induced vascular smooth muscle cell migration'. Together they form a unique fingerprint.

Cite this