Abstract：
:A new kinetic model of the Na(+)/H(+) exchanger (NHE) was developed by fitting a variety of major experimental findings, such as ion-dependencies, forward/reverse mode, and the turnover rate. The role of NHE in ion homeostasis was examined by implementing the NHE model in a minimum cell model including intracellular pH buffer, Na(+)/K(+) pump, background H(+), and Na(+) fluxes. This minimum cell model was validated by reconstructing recovery of pH(i) from acidification, accompanying transient increase in [Na(+)](i) due to NHE activity. Based on this cell model, steady-state relationships among pH(i), [Na(+)](I), and [Ca(2+)](i) were quantitatively determined, and thereby the critical level of acidosis for cell survival was predicted. The acidification reported during partial blockade of the Na(+)/K(+) pump was not attributed to a dissipation of the Na(+) gradient across the membrane, but to an increase in indirect H(+) production. This NHE model, though not adapted to the dimeric behavioral aspects of NHE, can provide a strong clue to quantitative prediction of degree of acidification and accompanying disturbance of ion homeostasis under various pathophysiological conditions.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Cha CY,Oka C,Earm YE,Wakabayashi S,Noma Adoi
10.1016/j.bpj.2009.08.053subject
Has Abstractpub_date
2009-11-18 00:00:00pages
2674-83issue
10eissn
0006-3495issn
1542-0086pii
S0006-3495(09)01444-1journal_volume
97pub_type
杂志文章abstract：:The lateral mobility of the lipid analog N-4-nitrobenzo-2-oxa-1,3 diazole phosphatidylethanolamine and of the integral protein glycophorin in giant dimyristoylphosphatidylcholine vesicles was studied by the photobleaching technique. Above the temperature of the chain-melting transition (Tm = 23 degrees C), the diffusi...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(84)84195-8
更新日期：1984-03-01 00:00:00
abstract：:The properties of vesicle membranes prepared from 16:0-SM, 16:0-DHSM, or DPPC were characterized using steady-state and time-resolved fluorescence spectroscopy and different fluorescent reporter molecules. The acyl-chain region was probed using free and phospholipid-bound 1,6-diphenyl-1,3,5-hexatriene. 16:0-DHSM was f...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(03)74915-7
更新日期：2003-02-01 00:00:00
abstract：:Surface and subsurface dynamics of Rat Basophilic Leukemia cells, a model system of stimulated secretion, were imaged using Scanning Force Microscopy (SFM) at a rate of 50-60 s/image. Cytoskeletal elements and organelles were tracked within quiescent cells and those activated after IgE receptor crosslinking. In additi...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(94)80964-6
更新日期：1994-05-01 00:00:00
abstract：:Membrane proteins diffuse within the membrane, form oligomers and supramolecular assemblies. Using high-speed atomic force microscopy, we present direct experimental measure of an in-membrane-plane interaction potential between membrane proteins. In purple membranes, ATP-synthase c-rings formed dimers that temporarily...
journal_title：Biophysical journal
pub_type： 信件
doi：10.1016/j.bpj.2010.07.028
更新日期：2010-10-06 00:00:00
abstract：:Phosphorescence spectroscopy on mouse myeloma IgA J539 in rigid solution at 77K revealed the type of anomalous short-lived component in the tryptophan decay originally observed with lysozyme (Churchich, J.E., 1966. Biochim. Biophys. Acta. 120:406-412) and seen in a large number of Bence Jones proteins (Longworth, J.W....
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(89)82681-5
更新日期：1989-08-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(97)78106-2
更新日期：1997-08-01 00:00:00
abstract：:Viral infection begins with the binding of a virus to a specific target on the surface of the host cell, followed by viral genome delivery into the host and a continuation of the infection process. Before binding occurs, the virus must first find its receptor by a process whose details are largely unknown. We applied ...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2011.05.014
更新日期：2011-06-22 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2016.12.001
更新日期：2017-01-10 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2020.04.031
更新日期：2020-06-16 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(04)74170-3
更新日期：2004-02-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(98)77836-1
更新日期：1998-03-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2014.10.060
更新日期：2014-12-16 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2017.06.035
更新日期：2017-11-21 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(84)84145-4
更新日期：1984-01-01 00:00:00
abstract：:Conserved active-site elements in myosins and other P-loop NTPases play critical roles in nucleotide binding and hydrolysis; however, the mechanisms of allosteric communication among these mechanoenzymes remain unresolved. In this work we introduced the E442A mutation, which abrogates a salt-bridge between switch I an...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2012.04.025
更新日期：2012-06-06 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(81)84796-0
更新日期：1981-08-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2017.06.064
更新日期：2017-08-22 00:00:00
abstract：:It was shown previously that a significant fraction of the myosin crossbridges is attached to actin in the skinned rabbit psoas fibers under relaxed conditions at low ionic strength and low temperature (Brenner, B., M. Schoenberg, J. M. Chalovich, L. E. Greene, and E. Eisenberg. 1982. Proc. Natl. Acad. Sci. USA. 79:72...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(89)82838-3
更新日期：1989-03-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(83)84401-4
更新日期：1983-01-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(04)74241-1
更新日期：2004-03-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2013.12.025
更新日期：2014-02-04 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(96)79433-X
更新日期：1996-11-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(97)78761-7
更新日期：1997-03-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2017.11.025
更新日期：2018-01-23 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(02)75333-2
更新日期：2002-12-01 00:00:00
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journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(73)85996-X
更新日期：1973-05-01 00:00:00
abstract：:Transcription factor (TF) proteins rapidly locate unique target sites on long genomic DNA molecules--and bind to them--during gene regulation. The search mechanism is known to involve a combination of three-dimensional diffusion through the bulk of the cell and one-dimensional sliding diffusion along the DNA. It is be...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1529/biophysj.108.129825
更新日期：2008-08-01 00:00:00
abstract：:Physical origin of DNA condensation by multivalent cations remains unsettled. Here, we report quantitative studies of how one DNA-condensing ion (Cobalt(3+) Hexammine, or Co(3+)Hex) and one nonDNA-condensing ion (Mg(2+)) compete within the interstitial space in spontaneously condensed DNA arrays. As the ion concentrat...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/j.bpj.2013.07.004
更新日期：2013-08-20 00:00:00
abstract：:Phosphorus-31 nuclear magnetic resonance (31P-NMR) spectra were obtained from living toad retinae and toad retinal extracts at 4 degrees C. Several phosphorus metabolites--nucleoside di- and triphosphates (NTP), phosphocreatine, phosphodiesters, inorganic phosphate, and phosphomonoesters--were identified from the spec...
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(89)82691-8
更新日期：1989-09-01 00:00:00
abstract：:The shapes of fluorescence induction curves in spinach chloroplasts, measured using double-flash pump-probe techniques, are shown to depend on the duration of the actinic flashes. For flash durations tau(0)
journal_title：Biophysical journal
pub_type： 杂志文章
doi：10.1016/S0006-3495(91)82233-0
更新日期：1991-02-01 00:00:00
