Molecular cloning of a novel potassium-dependent sodium-calcium exchanger from rat brain

被引:109
作者
Tsoi, M
Rhee, KH
Bungard, D
Li, XF
Lee, SL
Auer, RN
Lytton, J
机构
[1] Univ Calgary, Hlth Sci Ctr, Dept Med Biochem, Calgary, AB T2N 4N1, Canada
[2] Univ Calgary, Dept Neurosci, Calgary, AB T2N 4N1, Canada
[3] Brigham & Womens Hosp, Dept Med, Div Renal, Boston, MA 02115 USA
[4] Harvard Univ, Sch Med, Boston, MA 02115 USA
关键词
D O I
10.1074/jbc.273.7.4155
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
We have isolated a novel cDNA clone from rat cerebral cortex encoding a protein of 670 amino acids (NCKX2) that has significant similarity to the 1199-amino acid-long Na/Ca-K exchanger of bovine rod outer segment (NCKX1), NCKX2 transcripts are 10.5 kilobase pairs in length and are expressed abundantly in neurons throughout the brain and with much lower abundance in selected other tissues, The predicted topology of the rat NCKX2 protein is very similar to that of bovine NCKX1, beginning with a solitary transmembrane segment (MO), which is removed as a "signal peptide" in bovine NCKX1, an extracellular loop, a cluster of five transmembrane spanning segments (Mi to M5), a long cytoplasmic loop, and a final hydrophobic cluster (M6 to M11), Within the hydrophobic clusters, rat NCKX2 shares 80% identity and 91% similarity with bovine NCKX1, The two larger hydrophilic loops are much shorter in NCKX2 than in NCKX1, accounting largely for the difference in length between the two proteins, and are dissimilar in sequence except for a 32-amino acid stretch with 69% identity in the cytosolic loop. NCKX2 was epitope-tagged in the extracellular domain and was shown to be expressed at the surface of transfected HEK cells. Analysis of NCKX2 function by fluorescent imaging of fura-a-loaded transfected cells demonstrated that NCKX2 is a potassium-dependent sodium/calcium exchanger.
引用
收藏
页码:4155 / 4162
页数:8
相关论文
共 45 条
  • [21] LYTTON J, 1992, J BIOL CHEM, V267, P14483
  • [22] The kidney sodium-calcium exchanger
    Lytton, J
    Lee, SL
    Lee, WS
    vanBaal, J
    Bindels, RJM
    Kilav, R
    NavehMany, T
    Silver, J
    [J]. SODIUM-CALCIUM EXCHANGE: PROCEEDINGS OF THE THIRD INTERNATIONAL CONFERENCE, 1996, 779 : 58 - 72
  • [23] REGIONAL DISTRIBUTION IN THE RAT CENTRAL-NERVOUS-SYSTEM OF A MESSENGER-RNA ENCODING A PORTION OF THE CARDIAC SODIUM-CALCIUM EXCHANGER ISOLATED FROM CEREBELLAR GRANULE NEURONS
    MARLIER, LNJL
    ZHENG, T
    TANG, J
    GRAYSON, DR
    [J]. MOLECULAR BRAIN RESEARCH, 1993, 20 (1-2): : 21 - 39
  • [24] COUPLING OF THE NA+/CA2+ EXCHANGER, NA+/K+ PUMP AND SARCOPLASMIC-RETICULUM IN SMOOTH-MUSCLE
    MOORE, EDW
    ETTER, EF
    PHILIPSON, KD
    CARRINGTON, WA
    FOGARTY, KE
    LIFSHITZ, LM
    FAY, FS
    [J]. NATURE, 1993, 365 (6447) : 657 - 660
  • [25] Electrophysiological characterization of ionic transport by the retinal exchanger expressed in human embryonic kidney cells
    Navangione, A
    Rispoli, G
    Gabellini, N
    Carafoli, E
    [J]. BIOPHYSICAL JOURNAL, 1997, 73 (01) : 45 - 51
  • [26] Mutation of amino acid residues in the putative transmembrane segments of the cardiac sarcolemmal Na+-Ca2+ exchanger
    Nicoll, DA
    Hryshko, LV
    Matsuoka, S
    Frank, JS
    Philipson, KD
    [J]. JOURNAL OF BIOLOGICAL CHEMISTRY, 1996, 271 (23) : 13385 - 13391
  • [27] Cloning of a third mammalian Na+-Ca2+ exchanger, NCX3
    Nicoll, DA
    Quednau, BD
    Qui, ZY
    Xia, YR
    Lusis, AJ
    Philipson, KD
    [J]. JOURNAL OF BIOLOGICAL CHEMISTRY, 1996, 271 (40) : 24914 - 24921
  • [28] MOLECULAR-CLONING AND FUNCTIONAL EXPRESSION OF THE CARDIAC SARCOLEMMAL NA+-CA-2+ EXCHANGER
    NICOLL, DA
    LONGONI, S
    PHILIPSON, KD
    [J]. SCIENCE, 1990, 250 (4980) : 562 - 565
  • [29] MOLECULAR OPERATIONS OF THE SODIUM CALCIUM EXCHANGER REVEALED BY CONFORMATION CURRENTS
    NIGGLI, E
    LEDERER, WJ
    [J]. NATURE, 1991, 349 (6310) : 621 - 624
  • [30] HOW CALMODULIN BINDS ITS TARGETS - SEQUENCE INDEPENDENT RECOGNITION OF AMPHIPHILIC ALPHA-HELICES
    ONEIL, KT
    DEGRADO, WF
    [J]. TRENDS IN BIOCHEMICAL SCIENCES, 1990, 15 (02) : 59 - 64