Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology

Maria Barthmes, Jun Liao, Youxing Jiang, Andrea Brüggemann, Christian Wahl-Schott

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Sodium-calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium-calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)-based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.

Original languageEnglish (US)
Pages (from-to)485-496
Number of pages12
JournalJournal of General Physiology
Volume147
Issue number6
DOIs
StatePublished - 2016

Fingerprint

Electrophysiology
Methanocaldococcus
Sodium-Calcium Exchanger
Technology
Membranes
Membrane Transport Proteins
Archaea
Protein Isoforms
Proteins
Homeostasis
Sodium
Ions
Calcium

ASJC Scopus subject areas

  • Physiology

Cite this

Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology. / Barthmes, Maria; Liao, Jun; Jiang, Youxing; Brüggemann, Andrea; Wahl-Schott, Christian.

In: Journal of General Physiology, Vol. 147, No. 6, 2016, p. 485-496.

Research output: Contribution to journalArticle

Barthmes, Maria ; Liao, Jun ; Jiang, Youxing ; Brüggemann, Andrea ; Wahl-Schott, Christian. / Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology. In: Journal of General Physiology. 2016 ; Vol. 147, No. 6. pp. 485-496.
@article{b4fea2bcbfd24bb6b329a7577af5c31b,
title = "Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology",
abstract = "Sodium-calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium-calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)-based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.",
author = "Maria Barthmes and Jun Liao and Youxing Jiang and Andrea Br{\"u}ggemann and Christian Wahl-Schott",
year = "2016",
doi = "10.1085/jgp.201611587",
language = "English (US)",
volume = "147",
pages = "485--496",
journal = "Journal of General Physiology",
issn = "0022-1295",
publisher = "Rockefeller University Press",
number = "6",

}

TY - JOUR

T1 - Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology

AU - Barthmes, Maria

AU - Liao, Jun

AU - Jiang, Youxing

AU - Brüggemann, Andrea

AU - Wahl-Schott, Christian

PY - 2016

Y1 - 2016

N2 - Sodium-calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium-calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)-based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.

AB - Sodium-calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium-calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)-based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.

UR - http://www.scopus.com/inward/record.url?scp=84973525447&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84973525447&partnerID=8YFLogxK

U2 - 10.1085/jgp.201611587

DO - 10.1085/jgp.201611587

M3 - Article

VL - 147

SP - 485

EP - 496

JO - Journal of General Physiology

JF - Journal of General Physiology

SN - 0022-1295

IS - 6

ER -