The involvement of sodium in the function of the human amino acid transporter ASCT2

© 2021 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies..

Alanine, serine, cysteine transporter 2 (ASCT2) is a membrane amino acid transporter with relevance to human physiology and pathology, such as cancer. Notwithstanding, the study on the ASCT2 transport cycle still has unknown aspects, such as the role of Na+ in this process. We investigate this issue using recombinant hASCT2 reconstituted in proteoliposomes. Changes in the composition of purification buffers show the crucial role of Na+ in ASCT2 functionality. The transport activity is abolished when Na+ is absent or substituted by Li+ or K+ in purification buffers. By employing a Na+ fluorometric probe, we measured an inwardly directed flux of Na+ and, by combining fluorometric and radiometric assays, determined a 2Na+  : 1Gln stoichiometry. Kinetics of Na+ transport suggest that pH-sensitive residues are involved in Na+ binding/transport. Our results clarify the role of Na+ on human ASCT2 transporter activity.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:595

Enthalten in:

FEBS letters - 595(2021), 24 vom: 15. Dez., Seite 3030-3041

Sprache:

Englisch

Beteiligte Personen:

Mazza, Tiziano [VerfasserIn]
Scalise, Mariafrancesca [VerfasserIn]
Pappacoda, Gilda [VerfasserIn]
Pochini, Lorena [VerfasserIn]
Indiveri, Cesare [VerfasserIn]

Links:

Volltext

Themen:

0RH81L854J
451W47IQ8X
9NEZ333N27
ASCT2
Amino Acid Transport System ASC
Fluorometric assay
Glutamine
Journal Article
Kinetics
Membrane transport
Minor Histocompatibility Antigens
Proteolipids
Proteoliposomes
Research Support, Non-U.S. Gov't
SLC
SLC1A5 protein, human
Sodium
Sodium Chloride

Anmerkungen:

Date Completed 11.01.2022

Date Revised 11.01.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/1873-3468.14224

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM332795926