Fig. 5. (A) A schematic representation of the contractile vacuole (CV) complex in Paramecium multimicronucleatum to show the pathways of the electric currents generated by V-ATPases in the radial arms. CV, contractile vacuole; RA1-RAN, the radial arms 1-N, where N is the total number of radial arms; i_H⁺, the current generated in a single radial arm; i_RA, the passive current across the radial arm membrane caused by i_H⁺; i_CV, the passive current across the CV membrane caused by i_H⁺ of those radial arms attached to the CV. (B) An electric circuit equivalent to A. r_CV, the input resistance of the CV; r_RA, the input resistance of a radial arm; SW, a switch corresponding to the attachment of the radial arm to (on) or detachment of the RA from (off) the CV; e_CV, CV potential. (C) Simulated stepwise changes in the e_CV based on the equivalent circuit (B) as a total of eight radial arms attach to the CV one by one. Numbers to the left signify potential steps as the radial arms are attached to the CV one by one.

Return to article