Essential role for NHERF in cAMP-mediated inhibition of the Na+-HCO3- co-transporter in BSC-1 cells

被引:28
作者
Weinman, EJ
Evangelista, CM
Steplock, D
Liu, MZ
Shenolikar, S
Bernardo, A
机构
[1] Univ Maryland, Sch Med, Dept Med, Baltimore, MD 21201 USA
[2] Univ Maryland, Sch Med, Dept Physiol, Baltimore, MD 21201 USA
[3] Dept Vet Affairs Med Ctr, Med Serv, Baltimore, MD 21201 USA
[4] Duke Univ, Med Ctr, Dept Pharmacol & Canc Biol, Durham, NC 27710 USA
[5] Univ Illinois, Dept Med, Nephrol Sect, Chicago, IL 60612 USA
[6] Chicago Vet Affairs Hlth Care Syst, W Side Div, Chicago, IL 60612 USA
关键词
D O I
10.1074/jbc.M106153200
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
Prior studies have indicated a requirement for the PDZ domain-containing protein, Na+/H+ Exchanger Regulatory Factor (NHERF), for protein kinase A (PKA)mediated inhibition of the renal basolateral Na+-HCO3- co-transporter (NBC). The present studies explore the potential mechanisms by which NHERF transduces cAMP signals to inhibit NBC. In BSC-1 cells, cells that express NBC but lack NHERF, 8-bromo-cAMP (100 mum for 15 min) failed to inhibit transport until wild-type mNHERF-(1-355) was expressed. mNHERF-(116-355) containing PDZ II and C-terminal ezrin-binding sequences or a mutant unphosphorylated form of rabbit NHERF effectively transduced the cAMP signals that inhibited NBC. By contrast, mNHERF-(1-126) encompassing N-terminal PDZ I and mNDERF-(1-325), which lacks ezrin-binding, failed to support cAMP inhibition of NBC activity. NBC and NHERF did not associate with each other in yeast two-hybrid or co-immunoprecipitation assays, and confocal microscopy indicated distinct subcellular localization of the two proteins. NBC was phosphorylated in BSC-1 cells, but its phosphorylation was not increased by cAMP nor was immunoprecipitated NBC phosphorylated by PKA in vitro. Acute exposure of mNHERF-(1-355)-expressing BSC-1 cells to cAMP did not change cell surface expression of NBC. Although these results established an essential role for NHERF in cAMP-mediated inhibition of NBC in BSC-1 cells, they also suggest a novel mechanism for NHERF-mediated signal transduction distinct from that previously characterized from studies of other NHERF targets.
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页码:42339 / 42346
页数:8
相关论文
共 23 条
[1]   ELECTROGENIC SODIUM-BICARBONATE COTRANSPORT IN RABBIT RENAL CORTICAL BASOLATERAL MEMBRANE-VESICLES [J].
AKIBA, T ;
ALPERN, RJ ;
EVELOFF, J ;
CALAMINA, J ;
WARNOCK, DG .
JOURNAL OF CLINICAL INVESTIGATION, 1986, 78 (06) :1472-1478
[2]   Basolateral Na+/HCO3- cotransport activity is regulated by the dissociable Na+/H+ exchanger regulatory factor [J].
Bernardo, AA ;
Kear, FT ;
Santos, AVP ;
Ma, JF ;
Steplock, D ;
Robey, RB ;
Weinman, EJ .
JOURNAL OF CLINICAL INVESTIGATION, 1999, 104 (02) :195-201
[3]   Cloning and functional expression of a human kidney Na+:HCO3- cotransporter [J].
Burnham, CE ;
Amlal, H ;
Wang, ZH ;
Shull, GE ;
Soleimani, M .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1997, 272 (31) :19111-19114
[4]   Acute regulation of Na+/H+ exchanger NHE3 by parathyroid hormone via NHE3 phosphorylation and dynamin-dependent endocytosis [J].
Collazo, R ;
Fan, LZ ;
Hu, MC ;
Zhao, H ;
Wiederkehr, MR ;
Moe, OW .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2000, 275 (41) :31601-31608
[5]   ANGIOTENSIN-II STIMULATES BOTH NA+-H+ EXCHANGE AND NA+/HCO-3 COTRANSPORT IN THE RABBIT PROXIMAL TUBULE [J].
GEIBEL, J ;
GIEBISCH, G ;
BORON, WF .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1990, 87 (20) :7917-7920
[6]   G protein-coupled receptor kinase 6A phosphorylates the Na+/H+ exchanger regulatory factor via a PDZ domain-mediated interaction [J].
Hall, RA ;
Spurney, RF ;
Premont, RT ;
Rahman, N ;
Blitzer, JT ;
Pitcher, JA ;
Lefkowitz, RJ .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1999, 274 (34) :24328-24334
[7]   PERITZ F-TEST - BASIC PROGRAM OF A ROBUST MULTIPLE COMPARISON TEST FOR STATISTICAL-ANALYSIS OF ALL DIFFERENCES AMONG GROUP MEANS [J].
HARPER, JF .
COMPUTERS IN BIOLOGY AND MEDICINE, 1984, 14 (04) :437-445
[8]  
JENTSCH TJ, 1986, J BIOL CHEM, V261, P2120
[9]   Identification of sites required for down-regulation of Na+/H+ exchanger NHE3 activity by cAMP-dependent protein kinase - Phosphorylation-dependent and -independent mechanisms [J].
Kurashima, K ;
Yu, FH ;
Cabado, AG ;
Szabo, EZ ;
Grinstein, S ;
Orlowski, J .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1997, 272 (45) :28672-28679
[10]   The role of NHERF and E3KARP in the cAMP-mediated inhibition of NHE3 [J].
Lamprecht, G ;
Weinman, EJ ;
Yun, CHC .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1998, 273 (45) :29972-29978