Anoctamin 6 mediates effects essential for innate immunity downstream of P2X7 receptors in macrophages

Nat Commun. 2015 Feb 5:6:6245. doi: 10.1038/ncomms7245.

Abstract

Purinergic P2X7 receptors (P2X7R) are fundamental to innate immune response. In macrophages, transient stimulation of P2X7R activates several transport mechanisms and induces the scrambling of phospholipids with subsequent membrane blebbing and apoptosis. These processes support phagocytosis and subsequent killing of phagocytosed bacteria. Here we demonstrate that the stimulation of P2X7 receptors activates anoctamin 6 (ANO6, TMEM16F), a protein that functions as Ca(2+) dependent phospholipid scramblase and Ca(2+)-activated Cl(-) channel. Inhibition or knockdown of ANO6 attenuates ATP-induced cell shrinkage, cell migration and phospholipid scrambling. In mouse macrophages, Ano6 produces large ion currents by stimulation of P2X7 receptors and contributes to ATP-induced membrane blebbing and apoptosis, which is largely reduced in macrophages from Ano6-/- mice. ANO6 supports bacterial phagocytosis and killing by mouse and human THP-1 macrophages. Our data demonstrate that anoctamin 6 is an essential component of the immune defense by macrophages.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anoctamins
  • Apoptosis / genetics
  • Apoptosis / immunology
  • Calcium / metabolism
  • Cell Movement
  • Cell Size
  • Gene Expression Regulation
  • Humans
  • Immunity, Innate*
  • Ion Transport
  • Macrophage Activation
  • Macrophages / cytology
  • Macrophages / immunology*
  • Mice
  • Mice, Knockout
  • Oocytes / cytology
  • Oocytes / metabolism
  • Patch-Clamp Techniques
  • Phagocytosis / genetics
  • Phospholipid Transfer Proteins / antagonists & inhibitors
  • Phospholipid Transfer Proteins / deficiency
  • Phospholipid Transfer Proteins / genetics
  • Phospholipid Transfer Proteins / immunology*
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Receptors, Purinergic P2X7 / genetics
  • Receptors, Purinergic P2X7 / immunology*
  • Signal Transduction
  • Xenopus laevis

Substances

  • ANO6 protein, human
  • Anoctamins
  • P2RX7 protein, human
  • Phospholipid Transfer Proteins
  • RNA, Small Interfering
  • Receptors, Purinergic P2X7
  • Calcium