Document Detail


Transitions from alkaline spots to regular bands during pH pattern formation at the plasmalemma of Chara cells.
MedLine Citation:
PMID:  12734703     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
A scanning pH-microprobe was used to study pH patterns near the surface of Chara corallina cells at various light intensities and during light-induced transitions from homogeneous pH distribution to alternating pH bands. In the irradiance (PAR) range 4-400 micromol quanta m(-2) s(-1), the sustained pH profiles consisted of alternating acid and alkaline bands with a characteristic length of 7-10 mm and pH shifts as large as 2-3 units. At lower irradiance, the number of alkaline bands decreased while the amplitude of remaining peaks stayed high. On cyclic changes in light intensity, a hysteresis of pH banding was observed: the pH bands tolerated low irradiance in weakening light, but higher irradiance was required for their emergence after dark adaptation of the cell. The pH profiles measured for different paths of electrode scanning suggest that the pH pattern at low light level represents patches coexisting with bands. The exposure of the cell to high-intensity light led to formation of radially symmetrical bands. Transformations of the pH pattern induced by lowering the light intensity were similar to those induced by transcellular electric current (1.5-3 microA). The data suggest that band formation at the plasmalemma of Chara cells proceeds through the initial appearance of multiple patches with a localized H(+)-transporting activity and subsequent spot rearrangements (fusion, deletions, widening), leading to establishment of alternating bands.
Authors:
A A Bulychev; S V Zykov; A B Rubin; S C Müller
Related Documents :
1526893 - Differential effects of ear-canal pressure and contralateral acoustic stimulation on ev...
2232823 - Frequency specific modulation of bone adaptation by induced electric fields.
20537773 - Ozone exposure and stomatal sluggishness in different plant physiognomic classes.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2003-03-06
Journal Detail:
Title:  European biophysics journal : EBJ     Volume:  32     ISSN:  0175-7571     ISO Abbreviation:  Eur. Biophys. J.     Publication Date:  2003 May 
Date Detail:
Created Date:  2003-05-07     Completed Date:  2004-03-12     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8409413     Medline TA:  Eur Biophys J     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  144-53     Citation Subset:  IM    
Affiliation:
Biophysics Department, Faculty of Biology, Moscow State University, 119899 Moscow, Russia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adaptation, Physiological
Cell Membrane / chemistry*,  radiation effects*
Cells, Cultured
Chara / chemistry*,  radiation effects*
Dose-Response Relationship, Radiation
Electromagnetic Fields
Hydrogen-Ion Concentration
Light*
Molecular Probes
Nonlinear Dynamics
Chemical
Reg. No./Substance:
0/Molecular Probes

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Raman study of the thermal behaviour and conformational stability of basic pancreatic trypsin inhibi...
Next Document:  Occupational issues of allergic contact dermatitis.