Identification of the carbonic anhydrase II binding site in the Cl-/HCO3- anion exchanger AE1

被引:146
作者
Vince, JW
Reithmeier, RAF
机构
[1] Univ Toronto, Dept Med, Med Res Council Grp Membrane Biol, Toronto, ON M5S 1A8, Canada
[2] Univ Toronto, Dept Biochem, Med Res Council Grp Membrane Biol, Toronto, ON M5S 1A8, Canada
关键词
D O I
10.1021/bi992564p
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The human Cl-/HCO3- anion exchanger (AE1) possesses a binding site within its 33 residue carboxyl-terminal region (Ct) for carbonic anhydrase II (CAII). The amino acid sequence comprising this CAII binding site was determined by peptide competition and by testing the ability of truncation and point mutants of the Ct sequence to bind CAII with a sensitive microtiter plate binding assay. A synthetic peptide consisting of the entire 33 residues of the Ct (residues 879-911) could compete with a GST fusion protein of the Ct (GST-Ct) for binding to immobilized CAII, while a peptide consisting of the last 16 residues (896-911) could not. A series of truncation mutants of the GST-Ct showed that the terminal 21 residues of AE1 were not required for binding CAII. Removal of four additional residues (887-890) from the Ct resulted in loss of CAII binding. Acidic residues in this region (D887ADD) were critical for binding since mutating this sequence in the GST-Ct to DAAA, AAAA, or NANN caused loss of CAII binding. A GST-Ct construct mutated to D887ANE, the homologous sequence in AE2, could bind CAII. AE2 is a widely expressed anion exchanger and has a homologous Ct region with 60% sequence identity to AE1. A GST fusion protein of the 33 residue Ct of AE2 could bind to CAII similarly to the Ct of AE1. Tethering of CAII to an acidic motif within the Ct of anion exchangers may be a general mechanism for promoting bicarbonate transport across cell membranes.
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页码:5527 / 5533
页数:7
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共 42 条
[11]  
KIFOR G, 1993, J MEMBRANE BIOL, V134, P169
[12]  
Kopito R R, 1990, Int Rev Cytol, V123, P177, DOI 10.1016/S0074-7696(08)60674-9
[13]   PRIMARY STRUCTURE AND TRANSMEMBRANE ORIENTATION OF THE MURINE ANION-EXCHANGE PROTEIN [J].
KOPITO, RR ;
LODISH, HF .
NATURE, 1985, 316 (6025) :234-238
[14]  
LIEBERMAN DM, 1988, J BIOL CHEM, V263, P10022
[16]   CLONING AND CHARACTERIZATION OF BAND-3, THE HUMAN-ERYTHROCYTE ANION-EXCHANGE PROTEIN (AE1) [J].
LUX, SE ;
JOHN, KM ;
KOPITO, RR ;
LODISH, HF .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1989, 86 (23) :9089-9093
[17]   PH-DEPENDENT ASSOCIATION OF CARBONIC-ANHYDRASE (CA) WITH GASTRIC LIGHT MICROSOMAL-MEMBRANES ISOLATED FROM BOVINE ABOMASUM - PARTIAL CHARACTERIZATION OF MEMBRANE-ASSOCIATED ACTIVITY [J].
MANANES, AAL ;
DALEO, GR ;
VEGA, FV .
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY, 1993, 105 (01) :175-182
[18]   CARBONIC ANHYDRASE - CHEMISTRY PHYSIOLOGY AND INHIBITION [J].
MAREN, TH .
PHYSIOLOGICAL REVIEWS, 1967, 47 (04) :595-+
[19]   Effect of expressing the water channel aquaporin-1 on the CO2 permeability of Xenopus oocytes [J].
Nakhoul, NL ;
Davis, BA ;
Romero, MF ;
Boron, WF .
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 1998, 274 (02) :C543-C548
[20]   A di-acidic signal required for selective export from the endoplasmic reticulum [J].
Nishimura, N ;
Balch, WE .
SCIENCE, 1997, 277 (5325) :556-558