PMID- 17664347
OWN - NLM
STAT- MEDLINE
DCOM- 20071016
LR  - 20181113
IS  - 0022-1295 (Print)
IS  - 1540-7748 (Electronic)
IS  - 0022-1295 (Linking)
VI  - 130
IP  - 2
DP  - 2007 Aug
TI  - Enzymatic suppression of the membrane conductance associated with the glutamine 
      transporter SNAT3 expressed in Xenopus oocytes by carbonic anhydrase II.
PG  - 203-15
AB  - The transport activity of the glutamine/neutral amino acid transporter SNAT3 
      (former SN1, SLC38A3), expressed in oocytes of the frog Xenopus laevis is 
      associated with a non-stoichiometrical membrane conductance selective for Na(+) 
      and/or H(+) (Schneider, H.P., S. Broer, A. Broer, and J.W. Deitmer. 2007. J. 
      Biol. Chem. 282:3788-3798). When we expressed SNAT3 in frog oocytes, the 
      glutamine-induced membrane conductance was suppressed, when carbonic anhydrase 
      isoform II (CAII) had been injected into the oocytes. Transport of substrate, 
      however, was not affected by CAII. The reduction of the membrane conductance by 
      CAII was dependent on the presence of CO(2)/HCO(3)(-), and could be reversed by 
      blocking the catalytic activity of CAII by ethoxyzolamide (10 microM). 
      Coexpression of wild-type CAII or a N-terminal CAII mutant with SNAT3 also 
      reduced the SNAT3- associated membrane conductance. The catalytically inactive 
      CAII mutant V143Y coexpressed in oocytes did not affect SNAT3-associated membrane 
      conductance. Our results reveal a new type of interaction between CAII and a 
      transporter-associated cation conductance, and support the hypothesis that the 
      transport of substrate and the non-stoichiometrical ion conductance are 
      independent of each other. This study also emphasizes the importance of carbonic 
      anhydrase activity and the presence of CO(2)-bicarbonate buffers for membrane 
      transport processes.
FAU - Weise, Alexandra
AU  - Weise A
AD  - Abteilung fur Allgemeine Zoologie, FB Biologie, Universitaet Kaiserslautern, 
      D-67653 Kaiserslautern, Germany.
FAU - Becker, Holger M
AU  - Becker HM
FAU - Deitmer, Joachim W
AU  - Deitmer JW
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Gen Physiol
JT  - The Journal of general physiology
JID - 2985110R
RN  - 0 (Amino Acid Transport Systems, Neutral)
RN  - 0 (Isoenzymes)
RN  - 0 (system N protein 1)
RN  - EC 4.2.1.- (Carbonic Anhydrase II)
SB  - IM
MH  - Amino Acid Transport Systems, Neutral/genetics/*metabolism
MH  - Animals
MH  - Biological Transport/drug effects/physiology
MH  - Carbonic Anhydrase II/genetics/*metabolism
MH  - Cattle
MH  - Electrophysiology
MH  - Escherichia coli
MH  - Female
MH  - Gene Expression Regulation
MH  - Hydrogen-Ion Concentration
MH  - Isoenzymes/genetics/metabolism/pharmacology
MH  - Membrane Potentials/drug effects/*physiology
MH  - Mutation/genetics
MH  - Oocytes/drug effects/*metabolism
MH  - Patch-Clamp Techniques
MH  - Rats
MH  - Xenopus laevis
PMC - PMC2151638
EDAT- 2007/08/01 09:00
MHDA- 2007/10/17 09:00
PMCR- 2008/02/01
CRDT- 2007/08/01 09:00
PHST- 2007/08/01 09:00 [pubmed]
PHST- 2007/10/17 09:00 [medline]
PHST- 2007/08/01 09:00 [entrez]
PHST- 2008/02/01 00:00 [pmc-release]
AID - jgp.200709809 [pii]
AID - 200709809 [pii]
AID - 10.1085/jgp.200709809 [doi]
PST - ppublish
SO  - J Gen Physiol. 2007 Aug;130(2):203-15. doi: 10.1085/jgp.200709809.