Mechanically induced avoidance response of chloroplasts in fern protonemal cells.
Cell response to mechanical stimulation was investigated at a subcellular level in protonemal cells of the fern Adiantum capillus-veneris L. by pressing a small part of the cell with a microcapillary. In cells receiving local stimulation, the chloroplasts moved away from the site of stimulation, whereas the nuclei failed to show such avoidance movement. Mechanical stimulation for a period as short as 0.3 min was enough to induce the avoidance response to a maximal level. The avoidance movement of chloroplasts started within 30 min and the plateau level of avoidance was attained around 2 h after stimulation. By tracing the movement of chloroplasts during the response, it was shown that the mobility of chloroplasts near the stimulation site increased transiently within 1 h after the stimulation. After 2 to 3 h, it slowed down to the control level without stimulation. The avoidance response was inhibited by 0.1 mM cytochalasin B and 25 mM 2, 3-butanedione monoxime but not by 3.3 microM amiprophosmethyl or 5 mM colchicine. These findings indicate that the protonemal cells were very sensitive to mechanical stimulation and that chloroplasts moved away from the mechanically stimulated site through the actomyosin motile system.
Sato
Y
Y
Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Minami-Osawa 1-1, Hachioji, Tokyo 192-0397, Japan.
Kadota
A
A
Wada
M
M
D000205:Actomyosin / Q000378:metabolism; D002467:Cell Nucleus / Q000502:physiology; D002736:Chloroplasts / Q000187:drug effects / Q000502:physiology*; D003078:Colchicine / Q000494:pharmacology; D003571:Cytochalasin B / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology; D003931:Diacetyl / Q000031:analogs & derivatives / Q000494:pharmacology; D008954:Models, Biological; D009068:Movement / Q000187:drug effects; D009578:Nitrobenzenes; D009946:Organothiophosphorus Compounds / Q000494:pharmacology; D010812:Physical Stimulation; D059828:Plant Cells; D010944:Plants / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors
D009578:Nitrobenzenes; D009946:Organothiophosphorus Compounds; C004717:diacetylmonoxime; C017823:amiprophos methyl; D003571:Cytochalasin B; D000205:Actomyosin; D003931:Diacetyl; D003078:Colchicine