Integrin-mediated membrane blebbing is dependent on sodium-proton exchanger 1 and sodium-calcium exchanger 1 activity

J Biol Chem. 2012 Mar 23;287(13):10316-10324. doi: 10.1074/jbc.M111.244962. Epub 2012 Jan 23.

Abstract

Integrin signaling and membrane blebbing modulate cell adhesion, spreading, and migration. However, the relationship between integrin signaling and membrane blebbing is unclear. Here, we show that an integrin-ligand interaction induces both membrane blebbing and changes in membrane permeability. Sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are membrane proteins located on the bleb membrane. Inhibition of NHE1 disrupts membrane blebbing and decreases changes in membrane permeability. However, inhibition of NCX1 enhances cell blebbing; cells become swollen because of NHE1 induced intracellular sodium accumulation. Our study found that NHE1 induced sodium influx is a driving force for membrane bleb growth, while sodium efflux (and calcium influx) induced by NCX1 in a reverse mode results in membrane bleb retraction. Together, these findings reveal a novel function for NHE1 and NCX1 in membrane blebbing and permeability, and establish a link between membrane blebbing and integrin signaling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Calcium / metabolism*
  • Cation Transport Proteins / genetics
  • Cation Transport Proteins / metabolism*
  • Cell Membrane Permeability / physiology
  • Cell Membrane Structures / genetics
  • Cell Membrane Structures / metabolism*
  • Cricetinae
  • Cricetulus
  • Humans
  • Integrins / genetics
  • Integrins / metabolism*
  • Ion Transport / physiology
  • Signal Transduction / physiology
  • Sodium / metabolism*
  • Sodium-Calcium Exchanger / genetics
  • Sodium-Calcium Exchanger / metabolism*
  • Sodium-Hydrogen Exchanger 1
  • Sodium-Hydrogen Exchangers / genetics
  • Sodium-Hydrogen Exchangers / metabolism*

Substances

  • Cation Transport Proteins
  • Integrins
  • SLC9A1 protein, human
  • Sodium-Calcium Exchanger
  • Sodium-Hydrogen Exchanger 1
  • Sodium-Hydrogen Exchangers
  • sodium-calcium exchanger 1
  • Sodium
  • Calcium