scholarly journals Studies on the mechanism of cell elongation in Blepharisma japonicum II. Changes of the membrane potential measured by an electrode sensitive to tetraphenyl phosphonium.

1990 ◽  
Vol 15 (5) ◽  
pp. 251-256 ◽  
Author(s):  
Masaki Ishida ◽  
Kozo Utsumi ◽  
Toshinobu Suzaki ◽  
Yoshinobu Shigenaka
Keyword(s):  
Membrane Potential ◽  
Cell Elongation ◽  
Blepharisma Japonicum

Effect of quinclorac on auxin-induced growth, transmembrane proton gradient and ethylene biosynthesis in Echinochloa spp.

1998 ◽  
Vol 25 (7) ◽  
pp. 851 ◽  
Author(s):  
Nuria Lopez-Martinez ◽  
Richard H. Shimabukuro ◽  
Rafael De Prado
Keyword(s):  
Membrane Potential ◽  
Cell Membrane ◽  
Atpase Activity ◽  
Cell Elongation ◽  
Acc Synthase ◽  
Ethylene Biosynthesis ◽  
Elongation Growth ◽  
Ethylene Formation ◽  
Acc Content ◽  
Stimulation Of

The mechanism of action of quinclorac and its selectivity between rice and resistant (R), intermediately tolerant (I) and susceptible (S) Echinochloa spp. were investigated. The effect on the cell membrane potential (Em), stimulation of cell elongation growth, ACC production and ethylene formation were examined to verify the auxin characteristics of quinclorac and the possible mechanism of selectivity. Quinclorac did not induce cell elongation growth, neither did it cause hyperpolarization of Em due to the stimulation of H+ -ATPase activity. Quinclorac increased ethylene biosynthesis by increasing the ACC content in susceptible plants, possibly by affecting the autonomous auxin-regulated ACC synthase gene. Increased ethylene biosynthesis was correlated with the phytotoxicity of quinclorac. Ethylene biosynthesis due to quinclorac treatment in I and S biotypes increased 3 and 7 times, respectively, but quinclorac treatment had no effect on ethylene biosynthesis in R Echinochloa spp. and rice at the applied dosages. Quinclorac caused an increase of ACC concentration in the S biotype that was 2.5-fold more than the control. The addition of an ethylene biosynthesis inhibitor decreased the phytotoxicity of quinclorac. The mechanism of selectivity between susceptible and tolerant species/biotypes may be related to the formation of HCN as a coproduct during the stimulation of the ethylene biosynthesis caused by the herbicide only in susceptible grasses.

Visualization of the interaction between Gβγ and tubulin during light-induced cell elongation of Blepharisma japonicum

2010 ◽  
Vol 9 (8) ◽  
pp. 1101 ◽  
Author(s):  
Katarzyna Sobierajska ◽  
Joanna Głos ◽  
Joanna Dąborowska ◽  
Joanna Kucharska ◽  
Cezary Bregier ◽  
...  
Keyword(s):  
Cell Elongation ◽  
Blepharisma Japonicum

Studies on the mechanism of cell elongation in Blepharisma japonicum

1991 ◽  
Vol 26 (3-4) ◽  
pp. 365-369 ◽  
Author(s):  
Masaki Ishida ◽  
Yoshinobu Shigenaka ◽  
Toshinobu Suzaki ◽  
Koji Taneda
Keyword(s):  
Cell Elongation ◽  
Blepharisma Japonicum

Electrochemical Evidence of Specific Action of Indole Acetic Acid on Membranes in Mnium Leaves

1972 ◽  
Vol 27 (10) ◽  
pp. 1239-1242 ◽  
Author(s):  
U. Lüttge ◽  
N. Higinbotham ◽  
C. K. Pallaghy
Keyword(s):  
Acetic Acid ◽  
Membrane Potential ◽  
Cell Elongation ◽  
Indole Acetic Acid ◽  
Recent Model ◽  
Salt Solutions ◽  
Proton Extrusion ◽  
Nernst Potential

The effect of 5·10-7 and 5·10-6Μ IAA on K+, Cl- and SO4-- uptake by young and old Mnium gametophytes from 0.2 mM or 10 mM salt solutions has been investigated. These IAA concentrations selectively enhance K+ uptake from 0.2 mM KCl or K2SO4 in old gametophytes. IAA up to 10-5 M does not affect the membrane potential (P.D.). At 0.2 mM KCl the observed P.D. of -200 to - 220 mV is more negative than the calculated Nernst potential of +84 to +107 mV for Cl- and -136 to -157 mV for K+. These results are discussed in relation to a recent model of IAA regulation of cell elongation involving a proton extrusion pump.

Studies on the mechanism of cell elongation in Blepharisma japonicum

1991 ◽  
Vol 27 (1) ◽  
pp. 46-54 ◽  
Author(s):  
Masaki Ishida ◽  
Toshinobu Suzaki ◽  
Yoshinobu Shigenaka
Keyword(s):  
Cell Elongation ◽  
Blepharisma Japonicum

Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

1995 ◽  
Vol 53 ◽  
pp. 972-973
Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell
Keyword(s):  
Membrane Potential ◽  
Confocal Microscopy ◽  
Patch Clamp ◽  
Electrical Activity ◽  
Time Lapse ◽  
Neuronal Firing ◽  
Neuronal Membrane ◽  
Pituitary Cells ◽  
Patch Clamp Recording ◽  
Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

Fluorescent potentiometric dyes for membrane-potential imaging

1994 ◽  
Vol 52 ◽  
pp. 166-167
Author(s):  
Leslie M. Loew
Keyword(s):  
Membrane Potential ◽  
Single Cells ◽  
Quantitative Imaging ◽  
Optical Recording ◽  
Biological Processes ◽  
Major Focus ◽  
The Past ◽  
Excitable Systems ◽  
Major Application ◽  
The Impact

A major application of potentiometric dyes has been the multisite optical recording of electrical activity in excitable systems. After being championed by L.B. Cohen and his colleagues for the past 20 years, the impact of this technology is rapidly being felt and is spreading to an increasing number of neuroscience laboratories. A second class of experiments involves using dyes to image membrane potential distributions in single cells by digital imaging microscopy - a major focus of this lab. These studies usually do not require the temporal resolution of multisite optical recording, being primarily focussed on slow cell biological processes, and therefore can achieve much higher spatial resolution. We have developed 2 methods for quantitative imaging of membrane potential. One method uses dual wavelength imaging of membrane-staining dyes and the other uses quantitative 3D imaging of a fluorescent lipophilic cation; the dyes used in each case were synthesized for this purpose in this laboratory.

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