PMID- 21325825
OWN - NLM
STAT- MEDLINE
DCOM- 20110527
LR  - 20190212
IS  - 1421-9778 (Electronic)
IS  - 1015-8987 (Linking)
VI  - 27
IP  - 1
DP  - 2011
TI  - Substrate-dependent interference of carbonic anhydrases with the glutamine 
      transporter SNAT3-induced conductance.
PG  - 79-90
LID - 10.1159/000325208 [doi]
AB  - The glutamine transporter SNAT3 (SLC38A3), which also transports asparagine and 
      histidine, exchanges sodium for protons, and displays a non-stoichiometrical 
      conductance, which is suppressed by the catalytic activity of carbonic anhydrase 
      II (CAII). In this study, we show that this conductance of rat SNAT3, expressed 
      in Xenopus oocytes, is also suppressed following co-expression with CAI, CAIII, 
      CAIV, and CAII-H64A (mutant with impaired intramolecular H(+) shuttling). All CA 
      isoforms and the CAII mutant displayed catalytic activity in intact oocytes, 
      although in vitro studies had reported only very low catalytic activity of CAIII 
      and CAII-H64A. The CA-mediated suppression of conductance was only observed, 
      however, when glutamine, but not when asparagine, was the substrate. We 
      hypothesized that this substrate specificity of the CA action might be due to the 
      different ion selectivity induced by the different amino acid substrates, which 
      induce currents carried by sodium and/or protons. The ion selectivity and 
      conductance was dependent on both pH and extracellular sodium concentration for 
      glutamine and asparagine; however the sodium dependence of the conductance, when 
      asparagine was the substrate, was significantly greater at higher sodium 
      concentrations, which might explain the difference in the sensitivity of the 
      conductance to CAs. Given the presence of CAs in most cells, substrate sensing of 
      SNAT3 would be indicated by different membrane potential changes.
CI  - Copyright (c) 2011 S. Karger AG, Basel.
FAU - Weise, Alexandra
AU  - Weise A
AD  - Abteilung fur Allgemeine Zoologie, FB Biologie, University of Kaiserslautern, 
      Kaiserslautern, Germany.
FAU - Schneider, Hans-Peter
AU  - Schneider HP
FAU - McKenna, Robert
AU  - McKenna R
FAU - Deitmer, Joachim W
AU  - Deitmer JW
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20110211
PL  - Germany
TA  - Cell Physiol Biochem
JT  - Cellular physiology and biochemistry : international journal of experimental 
      cellular physiology, biochemistry, and pharmacology
JID - 9113221
RN  - 0 (Amino Acid Transport Systems, Neutral)
RN  - 0 (system N protein 1)
RN  - 4QD397987E (Histidine)
RN  - 7006-34-0 (Asparagine)
RN  - 9NEZ333N27 (Sodium)
RN  - EC 4.2.1.- (Carbonic Anhydrase I)
RN  - EC 4.2.1.- (Carbonic Anhydrase II)
RN  - EC 4.2.1.- (Carbonic Anhydrase III)
RN  - EC 4.2.1.- (Carbonic Anhydrase IV)
RN  - EC 4.2.1.1 (Carbonic Anhydrases)
SB  - IM
MH  - Amino Acid Substitution
MH  - Amino Acid Transport Systems, Neutral/*metabolism
MH  - Animals
MH  - Asparagine/metabolism
MH  - Carbonic Anhydrase I/metabolism
MH  - Carbonic Anhydrase II/metabolism
MH  - Carbonic Anhydrase III/metabolism
MH  - Carbonic Anhydrase IV/metabolism
MH  - Carbonic Anhydrases/genetics/*metabolism
MH  - Electrophysiological Phenomena
MH  - Histidine/metabolism
MH  - Hydrogen-Ion Concentration
MH  - Mutation
MH  - Oocytes/metabolism
MH  - Rats
MH  - Sodium/metabolism
MH  - Xenopus laevis/embryology/metabolism
EDAT- 2011/02/18 06:00
MHDA- 2011/05/28 06:00
CRDT- 2011/02/18 06:00
PHST- 2010/12/16 00:00 [accepted]
PHST- 2011/02/18 06:00 [entrez]
PHST- 2011/02/18 06:00 [pubmed]
PHST- 2011/05/28 06:00 [medline]
AID - 000325208 [pii]
AID - 10.1159/000325208 [doi]
PST - ppublish
SO  - Cell Physiol Biochem. 2011;27(1):79-90. doi: 10.1159/000325208. Epub 2011 Feb 11.