Braun, Franz-Josef and Hegemann, Peter (1999) Direct measurement of cytosolic calcium and pH in living Chlamydomonas reinhardtii cells. EUROPEAN JOURNAL OF CELL BIOLOGY, 78 (3). pp. 199-208. ISSN 0171-9335, 1618-1298
Full text not available from this repository. (Request a copy)Abstract
Intracellular free Ca2+ and H+ were quantified in Chlamydomonas reinhardtii, using the fluorescent ion indicators Fura-2 and BCECF We demonstrate that both indicators can be loaded into living cells as acetoxymethylesters. The esters were hydrolyzed intracellularly to genuine Fura-2 and BCECF capable of indicating changes in Ca-i(2+) and H-i(+). Fura-2 accumulated in the cytoplasm to a concentration of 50 mu M, whereas BCECF reached a concentration of 200 mu M, The average Ca-i(2+) was estimated to be 180+/-40nM and the average pH(i) was 7.4+/-0.1. To document the applicability of the ion indicators in Chlamydomonas, we tested their responses to several stimuli. We observed increases in cytoplasmic Ca2+ in response to elevated external Ca2+ or membrane-permeable acids, which are known to induce flagellar excision in Chlamydomonas. The membrane-permeable acids caused a decrease in cytoplasmic pH. Pulses of photosynthetically active light lead to transient pH(i) changes. Finally, concomitant measurements of rhodopsin-triggered and voltage-sensitive photocurrents indicated that Ca2+ influx is accompanied by a transient depolarisation of the plasmalemma, These experiments document that Fura-2 and BCECF are versatile dyes for studying various ionic processes in Chlamydomonas.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | SIGNAL-TRANSDUCTION; CYTOPLASMIC CALCIUM; FLUORESCENT-PROBES; PLANT-CELLS; FURA-2; CA-2+; CA2+; INDICATORS; PROTOPLASTS; INHIBITORS; Fura-2; BCECF; fluorescence measurements |
| Subjects: | 500 Science > 570 Life sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Biochemie, Genetik und Mikrobiologie > Lehrstuhl für Biochemie I |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 15 Nov 2022 10:02 |
| Last Modified: | 15 Nov 2022 10:02 |
| URI: | https://pred.uni-regensburg.de/id/eprint/48460 |
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