Abstract
The presence of calcium is essential for chloroplast movement induced by blue light in Lemna trisulca L. The regulatory role of calcium was confirmed by the inhibition of chloroplast movement by cytochalasin B and trifluoperazine. The calcium concentration in tissues was modified by ethylene glycol-bis(2-aminoethylether)-N,N,N′, N′-tetraacetic acid (EGTA), the calcium ionophore A23187 and La3+. Only a long period of incubation (12h) in EGTA or La3+ caused distrubances in chloroplast movement. This indicates that calcium influx is not essential for chloroplast movement. Those conditions that dramatically changed the internal calcium concentration, either applications of calcium ionophore A23187 and EGTA, or ionophore and La3+, markedly decreased the amplitude of response to blue-light pulses. This demonstrates that disturbances of chloroplast movement are observable only when internal stores of calcium are affected by Ca2+-antagonists. We suggest that the calcium involved in blue-light-induced chloroplast movement is derived from intracellular stores. The addition of Mg2+ to EGTA buffer counteracted its effect, indicating that Mg2+, as well as Ca2+, might possibly be involved in chloroplast movement.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
