Abstract
Equilibrated Paramecium caudatum cells exposed to a constant DC gradient reorient with their depolarized anterior ends toward the cathode (galvanotaxis). Voltage gradients were applied to cells swimming either horizontally or vertically. Their velocity and orientation were recorded and compared to unstimulated cells. The DC field increased the horizontal velocity (= reference) up to 175% (galvanokinesis). Swimming velocities saturated after 1 min and were unchanged during the following 4 min. The upward and downward swimming velocities of stimulated cells were below those of horizontal swimmers. The difference in vertical rates (determining gravikinesis) was independent of variations in absolute velocity. Normalization of vertical velocities to horizontal velocities (= 100%) separated DC-field dependent changes from gravity-induced changes in velocities. A weak voltage gradient (0.3 V/cm) was most effective in raising downward gravikinesis up to threefold (-202 μm/s) above the unstimulated reference (-66 μm/s) and to change sign of gravikinesis in upward swimmers (-43 μm/s →+33 μm/s). We conclude that DC-field stimulation is equivalent to a depolarizing bias on gravikinetic responses of Paramecium. The stimulation does not directly interfere with mechanoreception, but modulates somatic Ca2+ entry to induce contraction of the cell soma. This presumably affects the gating of gravisensory transduction channels.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Allen AD (1988) Cytology. In: Görtz HD (ed) Paramecium. Springer, Berlin Heidelberg New York Tokyo, pp 4–40
Bräucker R, Machemer-Röhnisch S, Machemer H (1994) Graviresponses in Paramecium and Didinium examined under varied hypergravity conditions. J Exp Biol 197: 271–294
Brehm P, Eckert R (1978) Calcium entry leads to inactivation of calcium channel in Paramecium. Science 202: 1203–1205
Deitmer JW (1981) Voltage and time characteristics of the potassium mechanoreceptor current in the ciliate Stylonychia. J Comp Physiol 141: 173–182
Deitmer JW (1983) Ca channels in the membrane of the hypotrich ciliate Stylonychia. In: Grinnell A, Moody WJ (eds) The physiology of excitable cells. Liss, New York, pp 51–63
Deitmer JW (1986) Voltage-dependence of two inward currents carried by calcium and barium in the ciliate Stylonychia. J Physiol (Lond) 380: 551–574
De Peyer J, Machemer H (1978a) Are receptor-activated ciliary motor responses mediated through voltage or current? Nature 276: 285–287
De Peyer J, Machemer H (1978b) Hyperpolarizing and depolarizing mechanoreceptor potentials in Stylonychia. J Comp Physiol 127: 255–266
Hudspeth AJ (1983) The hair cells of the inner ear. Sci Am 248: 42–52
Hudspeth AJ (1992) Hair-bundle mechanics and a model for mechanoelectrical transduction by hair cells. In: Corey DP, Rooper SD (eds) Sensory transduction. Rockefeller University Press, New York, pp 357–370
Hudspeth AJ, Gillespie PG (1994) Pulling springs to tune transduction: adaptation by vertebrate hair cells. Neuron 12: 1–9
Iwatsuki K, Naitoh Y (1982) Photoresponses in colourless Paramecium. Experientia 38: 1453–1454
Jahn T (1961) The mechanism of ciliary movement. I. Ciliary reversal and activation by electric current: the Ludloff phenomenon in terms of core and volume conductors. J Protozool 8: 369–380
Jerka-Dziadosz M, Jenkins LM, Nelson EM, Williams NE, JaeckelWilliams R, Frankel J (1995) Cellular polarity in ciliates: persistence of global polarity in a disorganized mutant of Tetrahymena thermophila that disrupts cytoskeletal organization. Dev Biol 169: 644–661
Koehler O (1926) Galvanotaxis. In: Bethe A, von Bergman G, Embden G, Ellinger A (eds) Handbuch der normalen und pathologischen Physiologie, vol 11. Springer, Berlin, pp 1027–1049
Machemer H (1986) Electromotor coupling in cilia. In: Lüttgau HC (ed) Membrane control of cellular activity. Fortschr Zool 33: 205–250
Machemer H (1988a) Electrophysiology. In: Görtz HD (ed) Paramecium. Springer, Berlin Heidelberg New York Tokyo, pp 185–215
Machemer H (1988b) Motor control of cilia. In: Görtz HD (ed) Paramecium. Springer, Berlin Heidelberg New York Tokyo, pp 216–235
Machemer H (1989) Cellular behaviour modulated by ions: electrophysiological implications. J Protozool 36: 463–487
Machemer H (1995) A theory of gravikinesis in Paramecium. Adv Space Res 17: 11–20
Machemer H, Bräucker R (1992) Gravireception and graviresponses in ciliates. Acta Protozool 31: 185–214
Machemer H, Deitmer JW (1985) Mechanoreception in ciliates. Progress in Sensory Physiology, vol 5. Springer, Heidelberg, pp 81–118
Machemer H, Machemer-Röhnisch S (1984) Mechanical and electric correlates of mechanoreceptor activation of the ciliated tail in Paramecium. J Comp Physiol A 154: 273–278
Machemer H, Machemer-Röhnisch S (1996) Is gravikinesis in Paramecium affected by swimming velocity? Festschrift Koichi Hiwatashi. Eur J Protistol (in press)
Machemer H, Machemer-Röhnisch S, Bräucker R, Takahashi K (1991) Gravikinesis in Paramecium: Theory and isolation of a physiological response to the natural gravity vector. J Comp Physiol A 168: 1–12
Machemer H, Bräucker R, Murakami A, Yoshimura K (1993a) Graviperception in unicellular organisms: a comparative behavioural study under short-term microgravity. Microgravity Sci Technol 5: 221–231
Machemer H, Machemer-Röhnisch S, Bräucker R (1993b) Velocity and graviresponses in Paramecium during adaptation and varied oxygen concentration. Arch Protistenkd 143: 285–296
Machemer-Röhnisch S, Bräucker R, Machemer H (1993) Neutral gravitaxis of gliding Loxodes exposed to normal and raised gravity. J Comp Physiol A 171: 779–790
Martinac B, Hildebrand E (1981) Electrically induced Ca2+ transport across the membrane of Paramecium caudatum measured by means of flow-through technique. BBA 649: 244–252
Mogami Y, Pernberg J sr, Machemer H (1990) Messenger role of calcium in ciliary electromotor coupling: a reassessment. Cell Calcium 11: 665–673
Monzer J (1995) Actin filaments are involved in cellular graviperception of the basidiomycete Flammulina velutipes. Eur J Cell Biol 66: 151–156
Nakaoka Y, Machemer H (1990) Effects of cyclic nucleotides and intracellular Ca2+ on voltage-activated ciliary beating in Paramecium. J Comp Physiol A 166: 401–406
Nakaoka Y, Tanaka H, Oosawa F (1984) Ca2+-dependent regulation of beat frequency of cilia in Paramecium. J Cell Sci 65: 223–231
Ogura A, Machemer H (1980) Distribution of mechanoreceptor channels in the Paramecium surface membrane. J Comp Physiol 135: 233–242
Ooya M, Mogami Y, Izumi-Kurotani A, Baba SA (1992) Gravity-induced changes in propulsion of Paramecium caudatum: a possible role of gravireception in protozoan behaviour. J Exp Biol 163: 153–167
Preston RR, Saimi Y, Kung C (1992a) Calcium current activated upon hyperpolarization of Paramecium tetraurelia. J Gen Physiol 100: 233–251
Preston RR, Saimi Y, Kung C (1992b) Calcium-dependent inactivation of the calcium current activated upon hyperpolarization of Paramecium tetraurelia. J Gen Physiol 100: 253–268
Sachs L (1984) Angewandte Statistik. Springer, Berlin Heidelberg New York Tokyo
Sievers A, Kruse S, Kuo-Huang LL, Wendt M (1989) Statoliths and microfilaments in plant cells. Planta 179: 275–278
Verworn M (1889) Psychophysiologische Protistenstudien. G Fischer, Jena
Volkmann (1992) Forschung unter reduzierter Schwerkraft. Teil I: Grundlagen der Gravitationsbiologie. Naturwissenschaften 79: 68–74
Watzke D (1995) Schwerkraftbeantwortung von Paramecium nach Erhöhung der cytoplasmatischen Dichte durch Eisenfütterung. Diplomarbeit, Fakultät für Biologie, Ruhr-Universität Bochum
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Machemer-Röhnisch, S., Machemer, H. & Bräucker, R. Electric-field effects on gravikinesis in Paramecium . J Comp Physiol A 179, 213–226 (1996). https://doi.org/10.1007/BF00222788
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00222788