Is Calmodulin Involved in Electrophysiology ofChara corallina?

Autor: M. J. Beilby, E. A. C. Macrobbie
Rok vydání: 1984
Předmět:
Zdroj: Journal of Experimental Botany. 35:568-580
ISSN: 1460-2431
0022-0957
DOI: 10.1093/jxb/35.4.568
Popis: The role of calmodulin in Chara was investigated using the antipsychotic drug trifluoperazine (TFP), which is known to bind to the calmodulin/Ca++ complex preventing it from carrying out its normal functions. At low concentration (4-0 ,uM), TFP had profound and irreversible effects on the electrophysiology of Chara plasmalemma. The resting p.d. depolarized and the membrane conductance decreased suggesting an inhibition of the proton pump. After several hours of exposure the membrane became leaky, as cells deteriorated. The excitation was also affected by TFP. Spontaneous repetitive firing was observed. The excitation increased in duration and the action potential peak depolarized to ~ + 20 mV. The cytoplasmic streaming was unaffected by TFP; the streaming rate at the resting potential remained unchanged when TFP was added to the medium, stoppage occurred at the time of excitation and the streaming slowly resumed.
Databáze: OpenAIRE